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The pathobiology of peritonitis
Abstract
The peritoneum is more than a mechanical covering that allows for the easy gliding of opposed peritoneal surfaces. The peritoneal mesothelial cells facilitate the action of powerful innate immune mechanisms. In addition, the peritoneal-associated lymphoid tissues contain unique cells that may play a crucial role in the localization of intraperitoneal infection. A clearer understanding of the molecular and cellular events underlying peritoneal functions in both the unstimulated and stimulated state will aid future treatment of peritonitis.
... for pulmonary tuberculosis in animals to avoid euthanasia as much as possible. They are also studying in the search for new, more effective vaccines that can significantly reduce the disease [4]. Being a zoonotic disease, it is important to control and regulate this disease in the world by different epidemiological means, which can be sanitary or medical [4]. ...
... They are also studying in the search for new, more effective vaccines that can significantly reduce the disease [4]. Being a zoonotic disease, it is important to control and regulate this disease in the world by different epidemiological means, which can be sanitary or medical [4]. Conclusions: It is fundamental for researchers to know the pulmonary anatomy and the different specific variations in animals to succeed in finding potential treatments. ...
... Stromal cells expressing stem cell markers are a major source of angiogenesis factors such as endothelial growth factor which may be related to its being used as a graft. [4]. Another reaction to omentum infection is the production of "host defense peptides", which are part of the immune defense system [5], also playing a modulating role, stimulating the division of epithelial cells and fibroblasts, vascular neogenesis, granulation tissue formation and wound healing. ...
... Omental blood flow increases, and stromal tissue expands when exposed in vitro or in vivo to a foreign body or bacterium. 4,11 Inflammatory, hemostatic, and chemotactic factors are produced, leading to the recruitment of inflammatory cells within the peritoneal cavity. [11][12][13] It is thought that this signaling of a "flying column" immune cell response, in association with the formation of a physical barrier, minimizes peritoneal contamination while synchronously promoting tissue healing 2,4,5,11 The adipose region of the omentum is home to the "milky spots" of Ranvier, which are thought to play a role in immunological defense. ...
... 4,11 Inflammatory, hemostatic, and chemotactic factors are produced, leading to the recruitment of inflammatory cells within the peritoneal cavity. [11][12][13] It is thought that this signaling of a "flying column" immune cell response, in association with the formation of a physical barrier, minimizes peritoneal contamination while synchronously promoting tissue healing 2,4,5,11 The adipose region of the omentum is home to the "milky spots" of Ranvier, which are thought to play a role in immunological defense. 1,12,57-63 At a microscopic level, these milky spots, formed during the 20th to 35th week of gestation, contain macrophages and lymphocytes, 60 in particular B cells at varying stages of proliferation and maturation. ...
... 13,15 These activated omental stromal cells are a major source of angiogenic and neurogenic factors (such as vascular endothelial-derived growth factor), which may contribute to its success as a graft material in treating chronic leg ulcers, necrotizing fasciitis, and soft tissue defects. 4,11,70 The Omentum as an Agent of Host Defense When activated, omental lymphocytes produce inflammatory cytokines, acute-phase proteins, and host-defense peptides (HDPs). 71,72 Host-defense peptides represent some of the most ancient elements of the innate immune system, and their role appears to be conserved across species-structural and functional attributes of mammalian hostdefense peptides are also seen in the genome of plants and insects. ...
The omentum, a large adipose-invested organ which hangs from the stomach and transverse colon to drape over the abdominal viscera, is the first intra-abdominal structure the acute care surgeon encounters at laparotomy; however, many have not considered it as anything more than a passive, inert or even vestigial organ that forms adhesions and 'gets in the way'.The omentum is now known, however, to be a regulator of fluid exchange into and out of the peritoneal cavity and is a storage site for dietary lipid. It has been observed to migrate towards and readily-adhere to areas of inflammation and peritoneal damage, forming a protective barrier and predisposing to adhesions. Despite a poor understanding of the molecular basis for these properties, surgeons have mimicked this innate activity, using pedicled portions of omentum as a source of biomaterial for bolstering repair of visceral defects and enteric anastomoses for over 80 years.A further active role for the omentum in host defense against intra-abdominal sepsis has been observed during the pro-inflammatory and re-modelling phases and this activity may provide an explanation for some of the inter-individual variability seen in response to intra-abdominal catastrophe.We performed a narrative review of the historical, surgical and immunology literature regarding the utility and perceptions surrounding the omentum, chronicling how anatomic, histologic and immunologic advances have facilitated the evolution in our understanding of the omentum of ancient religious sacrifice through inert biomechanical substrate to surgically-relevant immunologically-active organ with major host defense and tissue-repair potential.Review Article, Level III.
... 8 The omentum plays a role in peritoneal defense by adhering to sites of inflammation, clearing bacteria and other contaminants, and providing leukocytes for local immune response. 41 Leukocytes aggregate in the perivascular adipose tissue of the omentum, are present in different stages of maturation, and can easily enter or leave milky spots. 42 The milky spots architecture allows for direct exposure of postcapillary venules to peritoneal inflammatory stimuli such as peritonitis as a result of locally increased blood flow. ...
... Activated omentum becomes a reservoir of stromal cells that express stem cell markers and vascular endothelial-derived growth factor (VEGF). 41,53,54 Mature macrophages leave the milky spots and enter the peritoneal cavity, whereas neutrophils are recruited from the peripheral circulation and enter the peritoneal cavity via the post-capillary venules of the milky spots (i.e., trafficking). 55,56 Although omentectomy reduces the incidence of peritoneal dialysis catheter obstruction and improves peritoneal dialysis drainage it also impairs peritoneal defense mechanisms and reduces survival in experimental models of peritonitis. ...
Previously considered inert, the greater omentum is now thought to play a central role in intra-peritoneal immune defense. The intestinal microbiome has recently become a target for potential therapeutic interventions. A narrative review of the immune functions of the omentum was generated using the Scale for the Assessment of Narrative Review Articles (SANRA) guideline. Articles were selected from domains including surgical history, immunology, microbiology, and abdominal sepsis. Evidence suggests the intestinal microbiome may be responsible for some maladaptive physiologic responses in disease states, particularly intra-peritoneal sepsis. Elaborate crosstalk exists between the gut microbiome and the omentum, given its innate and adaptive immune capabilities. We summarize current knowledge, provide examples of how normal and abnormal microbiomes interface with the omentum, and illustrate their impact on surgical disease and its management.
... Diaphragmatic lymph vessels allow the particles to leave the peritoneal cavity. The opposite flow is prevented by unilateral valves within these lymphatic vessels (Heemken et al., 1997;Hall et al., 1998) (Figure 1). ...
... The exact events that follow the inoculation of the peritoneal cavity with bacteria and adjuvants of infection (blood, bile, barium sulfate), and the consequent translymphatic systemic spread are the subject of further research. In animal models, when bacteria are injected into the peritoneal cavity, they disappear even before polymorphonuclear leukocyte (PMN) influx, and can be found in diaphragmatic lymph vessels within 6 hours after injection (Hall et al., 1998). This suggests that one of the most important defense mechanisms of the peritoneal cavity is the direct absorption of bacteria into the diaphragmatic lymph vessels, and the con-sequent exposure of bacteria to systemic defense mechanisms such as tissue macrophages, reticuloendothelial cells and PMN. ...
Peritonitis signifies inflammation of peritoneum, whose cause is not specific. It can be regarded as local equivalent of systemic inflammatory response which is seen after any trigger of inflammation and referred to as systemic inflammatory response syndrome (SIRS). Peritonitis takes place together with many, complex pathophysiological changes on systemic and cellular level.
... L'autre route d'implantation est qualifiée de trans-lymphatique. Les cellules cancéreuses libres vont accéder à l'espace lymphatique sub-péritonéal au travers d'ouvertures, ou stomates, faites par les vaisseaux lymphatiques dans le mésothélium péritonéal (stomates, Figure 14, [107]). L'augmentation de la fréquence des mésothéliomes de la plèvre depuis les années 1970 est due à une exposition à l'amiante pour 50% des patients [112,113]. ...
... Microscopie électronique à balayage de cellules mésothéliales murines et d'un stomate adjacent repéré par une flèche rouge (x27 000)[107]. ...
Le développement de thérapies ciblées et des techniques d’imagerie est un défi majeur en santé, particulièrement dans les pathologies cancéreuses. Les carcinoses péritonéales sont habituellement causées par une dissémination de cellules tumorales au sein de la cavité abdominale, ce qui est le cas de 85% des patientes atteintes d'un cancer ovarien et plus de 10% des patients atteints d’un cancer colorectal. Dans les deux cas, les traitements consistent en une chirurgie (cytoréduction), aussi complète que possible, accompagnée de chimiothérapies. L'amélioration de la survie globale des patients passe par le développement de technologies parallèles comme de nouveaux outils diagnostiques pour détecter des implantations précoces dans le péritoine, le blocage de la dissémination de cellules cancéreuses pendant et après la chirurgie, ou encore la combinaison de chimiothérapies et de traitements ciblés intrapéritonéaux.Ce projet de thèse consiste à aborder ces différents aspects par l'utilisation d'un nanocontainer protéique multifonctionnel. L’objectif est d’optimiser cette protéine, appartenant à la famille des lectines, pour envisager son développement en tant qu'outil théranostique dans le cadre du diagnostic et des traitements de cancers épithéliaux. La lectine de Xerocomellus chrysenteron, à l’origine extraite d’un champignon supérieur comestible, présente une forte affinité pour un biomarqueur glycosidique des carcinomes, l’antigène de Thomsen-Friedenreich (antigène TF ou CD176). De plus, la présence d’une large cavité hydratée au centre de cet assemblage protéique (homotétramère) permet d’envisager le confinement et l’adressage spécifique de molécules thérapeutiques à des cellules épithéliales cancéreuses.Nous avons commencé par établir la preuve de concept de la délivrance ciblée de molécules thérapeutiques dans plusieurs lignées d’adénocarcinomes ovariens humains (OVCAR-3, SKOV-3, IGROV-1). Le marquage de la lectine dans le proche infrarouge a permis de confirmer le mécanisme de délivrance et prouver que la molécule thérapeutique avait bien été endocytée grâce à son confinement dans le nanocontainer. La protéine marquée a également été utilisée pour valider son utilisation comme nanosonde pour la détection de nodules tumoraux submillimétriques dans le péritoine. Cette détection est faite par imagerie de fluorescence in vivo dans des modèles précliniques de carcinose péritonéale ovarienne préalablement développés à partir de lignées cellulaires. La combinaison des deux propriétés de la protéine (sonde et container) permet d’envisager son utilisation en nanothéranostique intrapéritonéale. Afin de confirmer ce développement prometteur, il sera nécessaire d’établir la preuve de concept sur des modèles murins plus pertinents de la situation clinique développés à partir de tumeurs issues de patientes (Patient Derived Xenografts, PDX).
... Most experimental models studying systemic fungal diseases use IV injection of fungal cells which bypass mucosal host defenses and establish an infection predominantly in the kidney and the brain (41). This study utilized an IAC model to induce systemic inflammation mimicking a severe clinical concern of postoperative Candida peritonitis (42). Similar to IV-, IP-induced infection allows rapid blood dissemination of pathogens with exposure to an active population of phagocytes, complement cascade activation, and subsequent abscess formation in the peritoneal cavity (42). ...
... This study utilized an IAC model to induce systemic inflammation mimicking a severe clinical concern of postoperative Candida peritonitis (42). Similar to IV-, IP-induced infection allows rapid blood dissemination of pathogens with exposure to an active population of phagocytes, complement cascade activation, and subsequent abscess formation in the peritoneal cavity (42). Rapid fungal dissemination during experimental IAC was evident from considerably high C. albicans CFUs in the liver, spleen, and kidney of infected animals 24 h after inoculation ( Figure 1A). ...
Intra-abdominal infection (peritonitis) is a leading cause of severe disease in surgical intensive care units, as over 70% of patients diagnosed with peritonitis develop septic shock. A critical role of the immune system is to return to homeostasis after combating infection. S100A8/A9 (calprotectin) is an antimicrobial and pro-inflammatory protein complex used as a biomarker for diagnosis of numerous inflammatory disorders. Here we describe the role of S100A8/A9 in inflammatory collateral tissue damage (ICTD). Using a mouse model of disseminated intra-abdominal candidiasis (IAC) in wild-type and S100A8/A9-deficient mice in the presence or absence of S100A9 inhibitor paquinimod, the role of S100A8/A9 during ICTD and fungal clearance were investigated. S100A8/A9-deficient mice developed less ICTD than wild-type mice. Restoration of S100A8/A9 in knockout mice by injection of recombinant protein resulted in increased ICTD and fungal clearance comparable to wild-type levels. Treatment with paquinimod abolished ICTD and S100A9-deficient mice showed increased survival compared to wild-type littermates. The data indicates that S100A8/A9 controls ICTD levels and antimicrobial activity during IAC and that targeting of S100A8/A9 could serve as promising adjunct therapy against this challenging disease.
... The greater omentum is important for peritoneal immune homeostasis (Hall et al. 1998). Milky spots (MS) are lymphoid structures in the omentum that contribute to this function. ...
... MS are lymphoid structures that are located directly beneath the omental mesothelium; these structures participate in peritoneal immune defense (Hall et al. 1998). In addition, MS are primary implantation sites for peritoneal exfoliated cancer cells and therefore for omental metastasis (Hagiwara et al. 1993;Tsujimoto et al. 1995Tsujimoto et al. , 1996. ...
Milky spots are unique lymphoid structures in the greater omentum that participate in both immune homeostasis of the peritoneal cavity and formation of omental metastases. We developed a rapid and simple staining method to enable macro- or stereomicroscopic identification of these miniscule structures in large samples of fixed human greater omentum. By immersing approximately 6 × 4 cm samples of omental tissue in hematoxylin, these samples could be evaluated quickly for the presence of milky spots. We used an alum hematoxylin variant containing 1 g hematoxylin, 50 g aluminium ammonium sulfate, 0.2 g sodium iodide, 1 g citric acid and 50 g chloral hydrate. This staining method enabled us to determine the number, location, dimensions and topographical relation of milky spots to other structures. Our method also facilitates isolation of milky spots for further investigation. Hematoxylin imparts a blue color to the milky spots, which remains in place during further processing for paraffin embedding. This enabled easy recognition of milky spots during transfer through various solutions and permitted selection of relevant paraffin slides prior to additional staining.
... Injection of carrageenan into the peritoneal cavity induces several proinflammatory mediators such as prostaglandins, cytokines (IL-1β, TNF-α, IL-6), LTB 4 and C5a components, leukotrienes (B4 and PGE2) and chemokines (CXCL8) and CCL2). These inflammatory mediators stimulate increased vascular permeability and the migration of leukocytes and neutrophils to the abdominal cavity (Hall et al., 1998). Leukocyte migration has the role of recognizing and neutralizing foreign agents/aggressors, thus being an important step in the development of the inflammatory process (Kumar et al., 2014). ...
Background: Pogostemon heyneanus leaves infusions are relevant in ethnopharmacology for treating colds, coughs, headaches, and asthma.
Purpose: The essential oil chemical composition of a Pogostemon heyneanus specimen was monthly monitored from October 2021 to July 2022 to evaluate the climatic influences on its yield and chemical composition and antinociceptive, andanti-inflammatory properties.
Methods: The leaves, collected monthly over a 10-month period, were submitted to hydrodistillation. The oils obtained were analyzed by gas chromatography coupled to a mass spectrometer and gas chromatography coupled to flame ionization detector. The P. heyneanus essential oil (PhEO) was tested in vivo to evaluate its peripheral analgesic actions through the abdominal writhing test induced by acetic acid, and peripheral analgesia by tail immersion. Neurogenic and inflammatory pain were evaluated by formalin test, and acute oral toxicity of the oil was also verified.
Results: PhEO presented 27 chemical constituents with the highest predominance of patchoulol (43.6%–76.9%), α-bulnesene (0.2%–12.7%), α-guaiene (0.4%–8.9%), seychellene (3.8%–5.1%) and pogostol (0.0%–8.2%). The climatic parameters insolation, humidity, rainfall, and temperature did not influence the essential oil yield or the main chemical constituents, except for pogostol, which presented a strong (r = 0.73) and statistically significant (p < 0.05) correlation with temperature. PhEO did not display toxicity at the maximum 300 mg/kg dosage. The oil showed low peripheral and central analgesic action at 100 mg/kg, while in the neurogenic and inflammatory pain inhibition tests, no actions related to PhEO were observed. In the carrageenan-induced peritonitis test, PhEO did not reduce the migration of leukocytes to the peritoneal cavity compared to the control group.
Conclusion: Pogostemon heyneanus is a resistant plant to seasonal influences and a source of patchoulol. Despite ethnopharmacological indications, no in-vivo biological activities such as neurogenic or inflammatory pain were identified in the present work. So, the low influence of the climatic parameters on chemical composition can infer that the low pharmacological activity is also not subject to climatic variations, that is, it does not change due to the climate.
... Lysis of tumor and bacterial cells also might result, depending upon differences between cell and lavage fluid tonicity. Lavage can disperse or remove not only bacteria but also contaminants favoring bacterial proliferation such as blood, as well as proinflammatory cytokines that may exacerbate local inflammation [20,21]. However, lavage can interfere with peritoneal defense mechanisms [22] and mesothelial healing [23]; peritoneal mesothelium tends to slough after even brief exposure to air, saline, or other fluids [24][25][26]. ...
Background:
Although intraoperative peritoneal lavage often is performed routinely with the aim of reducing peritoneal contamination, evidence of lavage benefit in elective pancreatic surgery is limited.
Methods:
We retrospectively classified patients who had undergone pancreatic surgery to groups given or not given peritoneal lavage, then comparing clinical results. This saline lavage was performed at the end of the operation. The primary endpoint was rate of surgical site infection. Frequency of peritoneal recurrence also was evaluated.
Results:
Among all 104 patients in the study, incidence of infectious complications in the lavage group (n = 65) was significantly higher than in the non-lavage group (n = 39; 35% vs. 15%, P = 0.041), while incidences of postoperative complications overall and surgical site infection did not differ between lavage (80% and 26%) and non-lavage groups (67% and 10%, P = 0.162 and 0.076, respectively). Among 63 patients undergoing pancratoduodenectomy, frequencies of positive bacterial cultures of drainage fluids on postoperative days 1 and 3 were greater in the non-lavage group (P < 0.001 and P = 0.012), but surgical site infection was significantly more frequent in the lavage group (P = 0.043). Among patients with pancreatic and biliary cancers, lavage did not affect frequency of peritoneal recurrence.
Conclusion:
Intraoperative lavage did not prevent surgical site infection or peritoneal recurrence of pancreatobiliary cancer.
... When applied to the peritoneal cavity, carrageenan releases numerous inflammatory mediators, such as IL-1β, TNF-α, IL-8, prostanoids, LTB 4, and complement component C5a. These mediators cause vasodilation and increase vascular permeability, generating migration of leukocytes and neutrophils from the mesenteric venules to the peritoneal cavity (Hall et al., 1998). ...
Ethnopharmacological relevance:
The Eugenia uniflora leaf infusion is widely used in folk medicine to treat gastroenteritis, fever, hypertension, inflammatory and diuretic diseases.
Aim of the study:
This work evaluated the acute oral toxic, antinociceptive, and anti-inflammatory activities of the curzerene chemotype of Eugenia uniflora essential oil (EuEO).
Material and methods:
EuEO was obtained by hydrodistillation and analyzed by GC and GC-MS. The antinociceptive action in mice was evaluated for the peripheral and central analgesic activity using abdominal contortion and hot plate tests (50, 100, and 200 mg/kg); xylene-induced ear swelling was carried out for the nociception test, and carrageenan-induced cell migration test. Spontaneous locomotor activity was assessed in the open field test to rule out any nonspecific sedative or muscle relaxant effects of EuEO.
Results:
The EuEO displayed a yield of 2.6 ± 0.7%. The major compounds classes were oxygenated sesquiterpenoids (57.3 ± 0.2%), followed by sesquiterpene hydrocarbons (16.4 ± 2.6). The chemical constituents with the highest concentrations were curzerene (33.4 ± 8.5%), caryophyllene oxide (7.6 ± 2.8%), β-elemene (6.5 ± 1.8%), and E-caryophyllene (4.1 ± 0.3%). Oral treatment with EuEO, at doses of 50, 300, and 2000 mg/kg, did not change the behavior patterns or mortality of the animals. EuEO (300 mg/kg) did not cause a reduction in the number of crossings in the open field compared to the vehicle group. The aspartate aminotransferase (AST) level was higher in EuEO-treated groups (50 and 2000 mg/kg) when compared to the control group (p < 0.05). EuEO, at doses of 50, 100, and 200 mg/kg, reduced the number of abdominal writhings by 61.66%, 38.33%, and 33.33%. EuEO did not show increased hot plate test time latency in any of the intervals analyzed. At 200 mg/kg, EuEO decreased paw licking time, with inhibition of 63.43%. In formalin-induced acute pain, EuEO decreased paw licking time at doses of 50, 100, and 200 mg/kg in the first phase, with inhibition of 30.54%, 55.02%, and 80.87%. The groups treated with EuEO at doses of 50, 100, and 200 mg/kg showed ear edema reduction of 50.26%, 55.17%, and 51.31%, respectively. Moreover, EuEO inhibited leukocyte recruitment only at a dose of 200 mg/kg. The inhibitory values of leukocyte recruitment after 4 h of carrageenan application were 4.86%, 4.93%, and 47.25% for 50, 100, and 200 mg/kg of essential oil, respectively.
Conclusion:
The EuEO, curzerene chemotype, has significant antinociceptive and anti-inflammatory activities and low acute oral toxicity. This work confirms the antinociceptive and anti-inflammatory of this species as the traditional use.
... Причиной острого перитонита -воспаления брюшины -часто бывают ранения полых внутренних органов, некроз кишечника, несостоятельность анастомоза или опухолевые процессы. Последующее микробное загрязнение брюшной полости приводит к инфекции, в ответ на которую активируются иммунные механизмы [1]. Вне зависимости от этиологии и локализации воспалительного процесса брюшины в его активации и завершении ведущую роль играет иммунная система [2]. ...
Acute inflammation of the peritoneum – peritonitis – often develops after injury to hollow visceral organs, intestinal necrosis, failure of anastomosis, or tumor processes. Subsequent microbial contamination of the abdominal cavity leads to infection, in response to which immune mechanisms are activated. The pathogenesis of inflammatory processes in the abdominal cavity and their features are largely determined by the structure and function of the peritoneum, as well as its close connection with the omentum. An important point in resolving peritonitis is to maintain the balance of cytokines, the activity of immunocytes and complement functioning in the immune lymphoid clusters of the peritoneum and omentum, and their collaborative action during inflammation. The review presents data on the structure and function of the peritoneum and omentum, the role of neutrophil, macrophage, lymphocytic links of the immune system, as well as those of pro- and anti-inflammatory cytokines and complement in the development and cessation of acute inflammation in the abdominal cavity.
... Lysis of tumor and bacterial cells may also be accomplished, depending upon differences between cell and lavage uid tonicity. Lavage can disperse or remove not only bacteria but also contaminants favoring bacterial proliferation such as blood, as well as proin ammatory cytokines that may exacerbate local in ammation [15,16]. However, lavage can interfere with peritoneal defense mechanisms [17] and mesothelial healing [18]; peritoneal mesothelium tends to slough after even brief exposure to air, saline, or other uids [19][20][21]. ...
Background
Although intraoperative peritoneal lavage often is performed routinely with the aim of reducing peritoneal contamination, evidence of lavage benefit in elective pancreatic surgery is limited.
Methods
We retrospectively classified patients who had undergone pancreatic surgery to groups given or not given peritoneal lavage, then comparing clinical results. This saline lavage was performed at the end of the operation. The primary endpoint was rate of surgical site infection.
Results
Among all 104 patients in the study, incidence of infectious complications in the lavage group (n = 65) was significantly higher than in the non-lavage group (n = 39; 35% vs. 15%, P = 0.041), while incidences of postoperative complications overall and surgical site infection did not differ between lavage (80% and 26%) and non-lavage groups (67% and 10%, P = 0.162 and 0.076, respectively). Among 63 patients undergoing pancratoduodenectomy, frequencies of positive bacterial cultures of drainage fluids on postoperative days 1 and 3 were greater in the non-lavage group (P < 0.001 and P = 0.012), but surgical site infection was significantly more frequent in the lavage group (P = 0.043). Among patients with pancreatic and biliary cancer, lavage did not affect frequency of peritoneal recurrence.
Conclusions
Intraoperative lavage did not prevent surgical site infection or peritoneal recurrence of pancreatobiliary cancer.
... The omental tissue, enveloped by mesothelial cells, is primarily composed of white adipocytes and is interspersed with other stromal cells. Distinct from subcutaneous depots, the omentum has secondary lymphoid organs called the "milky spots" and carries out immune surveillance/defense in the peritoneal cavity [4,5]. These milky spots are arranged around a glomeruli-like network of capillaries and are comprised of B and T lymphocytes, macrophages, mast cells, and other stromal cells [6]. ...
The omentum is the metastatic site for intra-abdominal cancers such as colon, stomach, and ovarian (where it is the primary site for metastasis). Adipocytes are the primary cell type of the omentum, and they aid in cancer cell proliferation, migration, and invasion. Therefore, systematic characterization of adipocyte–cancer cell interactions will help in understanding the metastatic spread of intra-abdominal cancer. Here, a detailed mechanical-enzymatic digestion method describes the isolation of both normal and cancer-associated adipocyte from omental tissues.
... It is connected to the spleen, pancreas, and colon, and plays an important role in the function of the peritoneal cavity. Clinically, the omentum can often be found to move to the inflammation site of the peritoneal cavity, wrap the rupture and limit the inflammatory response [1] , which reduces peritonitis and promotes wound healing. The omentum is rich in a large number of blood vessels and lymphatic vessels, which can regulate the circulation of peritoneal fluid. ...
The great omentum is an intraperitoneal organ and plays an important role in protecting the environment of the peritoneal cavity. Several specialized innate immune cells including B1 cells and resident macrophages are found in the omentum, which may be attributed to the unique niche and its special stromal cells. However, it is not clear how these omental innate immune cells contribute to the peritoneal immunity. This review attempts to summarize the latest research on the omental innate immunity and discuss its involvement in the immune response of the peritoneal cavity.
... Due to its capacity to sequester abdominal inflammation, the omentum has traditionally been described (mainly by surgeons) as a policeman of the peritoneal cavity. [24]. The omental leukocyte clusters are termed milky spots (MSs) [25] which structures function as peritoneal exit ports for blood-borne leukocytes [9]. ...
Although not typical lymphoid organs, analysis of the visceral adipose-associated lymphoid tissues has recently substantially expanded our knowledge about the immunological features of these elusive compartments. Recent data have highlighted their considerable complexity in cellular organization and interactions in several biological processes, including adaptive immune responses, tissue plasticity to accommodate mesenchymal stem cells and progenitors, and providing a suitable microenvironment for serosal tumor propagation. This review aims to present a comprehensive view of the adipose-associated lymphoid tissues in local and systemic immune responsiveness, with particular emphasis on the omental and mesenteric lymphoid tissues in the serosal defense of abdominal organs.
... Therefore, more attention has been focused on autologous reconstruction, which is free of BIA-ALCL [23]. The greater omentum, whose blood is provided by the right and left gastroepiploic arteries, is a large apron-like fold of visceral peritoneum that contributes to the peritoneal defense mechanism [24]. The greater omentum can be an ideal autologous tissue as a substrate for breast reconstruction because it has a rich blood supply, is resistant to infection, is insusceptible to radiation, and is easily shaped for various breast defects [25]. ...
PurposeImmediate breast reconstruction using laparoscopically harvested omental flap is a safe and feasible technique, providing natural contour and softness to reconstructed breasts with reduced donor-site morbidity and deformity. We report our experience using single-port laparoscopically harvested omental flap (SLOF) for immediate breast reconstruction.Methods
Between February 2015 and December 2018, 129 patients with malignant neoplasm of the breast underwent nipple-sparing mastectomy (NSM) or breast-conserving surgery (BCS) followed by immediate SLOF reconstruction at Seoul National University Bundang Hospital. We assessed their clinicopathological data, complications, and cosmetic and oncologic outcomes. Cosmetic outcomes were evaluated by three-panel assessment and the BCCT.core software program.ResultsOne hundred and six (82.2%) underwent NSM and 23 (17.8%) underwent BCS. Mean operation time was 205 (range, 134–316) minutes. Most patients had early-stage disease; 15 (11.6%) received neoadjuvant chemotherapy. Two had malignant phyllodes tumors. Cosmetic outcomes were excellent or good in 96.9% by three-panel assessment and 99.2% by the BCCT.core program with a nearly invisible donor-site scar in the umbilicus. Harvest-associated complications occurred in five (3.9%) patients, including two umbilical wound infections, one intra-abdominal infection, one umbilical hernia, and one pedicle injury. Fat necrosis (13.2%) and epigastric bulging (21.7%) were common mastectomy- or reconstruction-associated complications, but most were mild and some resolved spontaneously. Over a median 38-month follow-up, there were three local, two regional, and three systemic recurrences.ConclusionsSLOF reconstruction is a feasible and safe option for immediate breast reconstruction after NSM or extensive BCS with minimal donor-site morbidity and great cosmetic outcomes.
... La superficie total del peritoneo es de 1,7 m 2 , estéril y contiene 50 mililitros de un líquido de color amarillo claro. 9,10 El peritoneo consta de una sola capa de células mesoteliales (Células Mesoteliales Peritoneales, CMP), sostenidas en una membrana basal sobre un lecho de tejido conjuntivo, 11 formado a su vez por células adiposas, macrógafos, fibroblastos, linfocitos y algunas fibras de colágeno. Las CMP pueden expresar en su superficie marcadores que les permiten: a) promover la marginación y migración de neutrófilos, b) interactuar con la matriz extracelular proteínica, c) presentar antígenos a las células inmunitarias y d) producir biológicamente moléculas importantes como citoquinas proinflamatorias (IL-6, IL-8 FNT alfa), óxido nítrico, factores de crecimiento, activador del plasminógeno tisular, e inhibidor del activador del plasminógeno, para así mismo combatir la colonización y eliminar elementos extraños. ...
La cirugía de abdomen abierto para el manejo de algunas patologías severas en obstetricia ha aumentado y actualmente es común en muchas de nuestras pacientes. Los beneficios incluyen la prevención y tratamiento del Síndrome de Hipertensión Intraabdominal (HIA), de las infecciones de la cavidad peritoneal y el del Síndrome Compartimental Abdominal (SCA) secundario a enfermedades potencialmente catastróficas como la preeclampsia severa y Síndrome de HELLP. La presente revisión explora los mecanismos de infección, las consecuencias fisio-patológicas del SCA y las nuevas técnicas quirúrgicas de la cirugía de abdomen abierto para el manejo adecuado de estas entidades.
... Therefore, the omentum has been recognised as having an important role in the immune defence, specifically in the peritoneal cavity. It plays this role by adhering to sites of inflammation, absorbing bacteria and other contaminants, and providing leukocytes for the local immune response [18]. ...
The Omentum is a large flat adipose tissue layer nestling on the surface of the intra-peritoneal organs. Besides fat storage, omentum has key biological functions in immune-regulation and tissue regeneration. Omentum biological properties include neovascularization, haemostasis, tissue healing and regeneration and as an in vivo incubator for cells and tissue cultivation. Some of these properties have long been noted in surgical practice and used empirically in several procedures. In this review article, the author tries to highlight the omentum biological properties and their application in regenerative surgery procedures. Further, he has started a process of standardisation of basic biological principles to pave the way for future surgical practice.
... The omentum is a visceral adipose tissue, mostly composed white adipose tissue that consisted of vascularized connective tissue, and doubled mesothelial layered membranous and translucent tissue [3]. The omentum, a main lipid storage and a source of bioactive factors, involves in the immune response and fluid exchange [4][5][6]. Milky spots are the primary functional units of the omentum [7,8], which are distributed along with the blood vessel networks [9]; detailed information of milky spots has been reviewed previously [10]. The structural components of milky spots are fibroblasts, adipocytes, mesothelial cells, endothelial cells, macrophages, stromal cells, and high endothelium of the vein, whereas the migratory components include lymphocytes, granulocytes, and monocytes [11]. ...
Accumulating evidence highlights the importance of interactions between tumour cells and stromal cells for tumour initiation, progression, and metastasis. In tumours that contain adipocyte in their stroma, adipocytes contribute to modification of tumour microenvironment and affect metabolism of tumour and tumour progression by production of cytokines and adipokines from the lipids. The omentum and bone marrow (BM) are highly adipocyte-rich and are also common metastatic and primary tumour developmental sites. Omental adipocytes exhibit metabolic cross-talk, immune modulation, and angiogenesis. BM adipocytes secrete adipokines, and participate in solid tumour metastasis through regulation of the CCL2/CCR2 axis and metabolic interactions. BM adipocytes also contribute to the progression of hematopoietic neoplasms. Here, we here provide an overview of research progress on the cross-talks between omental/BM adipocytes and tumour cells, which may be pivotal modulators of tumour biology, thus highlighting novel therapeutic targets.
Abbreviations: MCP-1, monocyte chemoattractant protein 1IL, interleukinSTAT3, signal transducer and activator of transcription 3FABP4, fatty acid binding protein 4PI3K/AKT, phosphoinositide 3-kinase/protein kinase BPPAR, peroxisome proliferator-activated receptorPUFA, polyunsaturated fatty acidTAM, tumour-associated macrophagesVEGF, vascular endothelial growth factorVEGFR, vascular endothelial growth factor receptorBM, bone marrowBMA, bone marrow adipocytesrBMA, regulated BMAcBMA, constitutive BMAUCP-1, uncoupling protein-1TNF-α, tumour necrosis factor-alphaRANKL, receptor activator of nuclear factor kappa-Β ligandVCAM-1, vascular cell adhesion molecule 1JAK2, Janus kinase 2CXCL (C–X–C motif) ligandPGE2, prostaglandin E2COX-2, cyclooxygenase-2CCL2, C-C motif chemokine ligand 2NF-κB, nuclear factor-kappa BMM, multiple myelomaALL, acute lymphoblastic leukemiaAML, acute myeloid leukemiaGDF15, growth differentiation factor 15AMPK, AMP-activated protein kinaseMAPK, mitogen-activated protein kinaseAPL, acute promyelocytic leukemiaCCR2, C-C motif chemokine receptor 2SDF-1α, stromal cell-derived factor-1 alphaFFA, free fatty acidsLPrA, leptin peptide receptor antagonistMCD, malonyl-CoA decarboxylase.
... It fulfills this function through immune aggregates located in its perivascular areas "milky spots", absorptive capabilities of germs and other contaminants, providing a layer of fibrin that consequently form collagen wall bounding and adhering the site of inflammation (Shimotsuma et al., 1993). Another well-known function of omentum is to maintain the intestine warm (Hall et al., 1998;Platell et al., 2000). ...
Mechanical ileus as the major cause of intestinal obstruction in cattle can arise from usual cases including complicated hernia, volvulus and intussusception. Our previous study reported some unusual cases causing ileus such as diaphragmatic hernia and internal localized abscessation in bovines. The purpose of this study was to define the diagnostic features and to show the representative images of other uncommon cases of mechanical ileus caused by omentum disorders in cattle. One-hundred-sixty-five cattle were referred to Veterinary Clinic of Zagazig University with abdominal distension and signs of ileus for clinical and abdominal ultrasound examinations. The anatomical and necropsy examinations were additionally involved in this study. Herein, we present uncommon cases of omentum- derived mechanical ileus in cattle. Among 165 total cases, ten cases (~6.1%) were identified as omentum disorders. More interestingly, as shown by the animal records, these ten animals underwent right omentopexy operation for correction of left displaced abomasum (LDA), 25±5 days pre- admission to the clinic. The following cases were reported: omental hernia (OH; 3 out of 10), omental fat necrosis (OFN; 2 out of 10) and omental bursitis (OB; 5 out 10). The observed necropsy findings confirmed the tentative diagnosis that was reached upon the ultrasonographic data. Based on the data presented here, omental affections should be involved during examination of cattle with mechanical ileus secondary to LDA surgical corrections.
... The omental fat tissue (Summers, 2006) generates numerous hormones and cytokines involved in immune responses and angiogenic and neurogenic factors (Chamorro et al., 1993;Goldsmith, 2001). It is a lipid store and pools immune cells, and it can adhere to neighboring peritoneum to embank local inflammation (Hall et al., 1998). ...
Peritoneal dialysis (PD) is a cost-effective, home-based therapy for patients with end-stage renal disease achieving similar outcome as compared to hemodialysis. Still, a minority of patients only receive PD. To a significant extend, this discrepancy is explained by major limitations regarding PD efficiency and sustainability. Due to highly unphysiological composition of PD fluids, the peritoneal membrane undergoes rapid morphological and long-term functional alterations, which limit the treatment and contribute to adverse patient outcome. This review is focused on the peritoneal membrane ultrastructure and its transformation in patients with kidney disease and chronic PD, underlying molecular mechanisms, and potential systemic sequelae. Current knowledge on the impact of conventional and second-generation PD fluids is described; novel strategies and innovative PD fluid types are discussed.
... On the peritoneal side of the diaphragm, the lymphatics serve as the primary site for absorption of peritoneal fluid (5,746,1087). These lymphatics also have a major defensive role against bacterial infections and inflammation in the peritoneal space, removing any pathogens or circulating immune cells due to infection or injury in the gastrointestinal or urogenitary systems (139,408,441,684). Lastly, the diaphragmatic lymphatic network, with subatmospheric luminal pressures lower than those in both the pleural and peritoneal spaces (discussed in the succeeding text), also prevents the flow of fluid from the peritoneal cavity into the pleural space (397). ...
The lymphatic system is comprised of a network of vessels interrelated with lymphoid tissue, which has the holistic function to maintain the local physiologic environment for every cell in all tissues of the body. The lymphatic system maintains extracellular fluid homeostasis favorable for optimal tissue function, removing substances that arise due to metabolism or cell death, and optimizing immunity against bacteria, viruses, parasites, and other antigens. This article provides a comprehensive review of important findings over the past century along with recent advances in the understanding of the anatomy and physiology of lymphatic vessels, including tissue/organ specificity, development, mechanisms of lymph formation and transport, lymphangiogenesis, and the roles of lymphatics in disease. © 2019 American Physiological Society. Compr Physiol 9:207‐299, 2019.
... Peritonitis is an inflammatory response to peritoneal injury. Injury results in an influx of protein rich fluid, activation of the complement cascade, upregulation of peritoneal mesothelial cell activity and invasion of the peritoneum with polymorphonuclear neutrophils and macrophages 1 . The pathogenesis of intra-abdominal infections is determined by bacterial factors which influence the transition from contamination to infection. ...
p> Background : Control of the primary site of sepsis is the main determinant of good surgical outcome.
Objective : The purpose of the present study was to compare the efficiency between povidone iodine and normal saline lavage in the treatment of acute peritonitis.
Methodology : This was a randomized clinical trial conducted in the Department of Surgery at Dhaka Medical College & Hospital, Dhaka, Bangladesh. Patients with acute peritonitis due to gastrointestinal causes who were admitted in the different units of Dhaka Medical College Hospital during the study period were selected as study population. Among them patients who were treated with povidone iodine were enrolled in the present study in group A and patients who were treated with conventional normal saline were in group B.
Results : A total number of 1050 patients were recruited for this study. Among them 100 patients were enrolled in the present study of which group A (50 patients) for povidone iodine and group B (50 patients) for conventional normal saline. On 7 th POD wound infection was found in Group A and Group B were 11(22.4%) and 21(44.7%) respectively. Statistically significant difference in post operative complication of wound infection was observed on 7 th POD between the groups (p<0.05). Post operative hospital stay in Group A and Group B were 11.50 ± 4.48 and 13.46 ± 5.13 days respectively. There is statistically significant difference in post operative hospital stay between the groups (p<0.05).
Conclusion : Statistically significant difference observed in post operative complication of wound infection and burst abdomen on 7 th POD between the groups. The present study there is statistically significant difference in post operative hospital stay between the groups also observed.
Bangladesh Journal of Infectious Diseases 2017;4(1):15-20
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... Un liquide ayant la composition proche d'un ultrafiltrat est secrété, puis réabsorbé dans la circulation générale par le feuillet pariétal. En microscopie électronique, des pores dit stomates permettent la communication entre ces deux domaines[3]. Ils sont localisés dans le territoire du péritoine diaphragmatique. ...
La péritonite aiguë communautaire, pathologie grave, se traite par la chirurgie avec l'adjonction d'une antibiothérapie initialement probabiliste. Les recommandations françaises de 2000 n'ont pas été réactualisées. Simultanément, les bactéries résistantes sont en pleine croissance. L'objectif de notre étude était d'évaluer la mobi-mortalité quand l'antibiothérapie empirique était inefficace. Matériel et méthodes : Étude rétrospective monocentrique au CHU de Rouen, de janvier 2010 à octobre 2012, nous avions évalué 99 patients atteints d'une péritonite aiguë communautaire, réanimatoire ou non. Un groupe "ATBproba +" (n = 33) et un groupe "ATBproba -" (n = 66) ont été comparés. Le travail analysait statistiquement l'impact sur la morbi-mortalité. Secondairement, les profils de sensibilité des protocoles d'antibiothérapies recommandées par le consensus français étaient recherchés. Résultats : En analyse globale, le taux de mortalité n'était pas différent entre les 33 patients ayant reçu une antibiothérapie initiale efficace et les 66 patients dont l'antibiothérapie empirique était résistante (12,1% vs 16,7%, p = 0,77). De même, le taux de guérison n'était pas significativement différent (69,7% vs 54,5%, p = 0,19). Les protocoles d'antibiothérapie initiale gardaient une sensibilité acceptable vis-à-vis de l'écologie bactérienne digestive. Conclusion : Dans notre population, la morbi-mortalité n'est pas impactée par l'efficacité de l'antibiothérapie initiale. Les recommandations SFAR 2000 restent d'actualité.
... Lavage has been proposed to remove bacterial contamination and other materials that may promote bacterial proliferation (e.g., blood) and proinflammatory cytokines that may enhance local inflammation. Therefore, flushing the peritoneal cavity may reduce the bacterial load, inhibit bacterial proliferation, and possibly minimize peritoneal adhesions [24][25][26]. Antibiotics may be combined with the lavage to further reduce bacterial survival. However, the efficacy of the lavage was not always demonstrated, though it must be considered that most studies were performed in cases of peritonitis [27]. ...
Background:
Surgical site infection (SSI) prevention bundles include the simultaneous use of different measures, which individually have demonstrated an effect on prevention of SSI. The implementation of bundles can yield superior results to the implementation of individual measures. The aim of this study was to address the effect of the application of a bundle including intraperitoneal lavage with antibiotic solution, fascial closure with Triclosan-coated sutures and Mupirocin ointment application on the skin staples, on the surgical site infection after elective laparoscopic colorectal cancer surgery.
Methods:
A prospective, randomized study was performed, including patients with diagnosis of colorectal neoplasms and plans to undergo an elective laparoscopic surgery. The patients were randomized into two groups: those patients following standard bundles (Group 1) and those ones following the experimental bundle with three additional measures, added to the standard bundle. Incisional and organ space SSI were investigated. The study was assessor-blinded.
Results:
A total of 198 patients were included in the study, 99 in each group. The incisional SSI rate was 16% in Group 1 and 2% in Group 2 [p = 0.007; RR = 5.6; CI 95% (1.4-17.8)]. The organ-space SSI rate was 4% in Group 1 and 0% in Group 2 [p = 0.039; RR = 1.7; CI 95% (1.1-11.6)]. Median hospital stay was 5.5 days in Group 1 and 4 days in Group 2 (p = 0.028).
Conclusions:
The addition of intraperitoneal lavage with antibiotic solution, fascial closure with Triclosan-coated sutures and Mupirocin ointment application on the skin staples, to a standard bundle of SSI prevention, reduces the incisional and organ-space SSI and consequently the hospital stay, after elective laparoscopic colorectal cancer surgery (ClinicalTrials.gov Identifier: NCT03081962).
... Lavage has been proposed to remove bacterial contamination and other materials that may promote bacterial proliferation (e.g., blood and proinflammatory cytokines) that may enhance local inflammation. Therefore, flushing the peritoneal cavity may reduce the bacterial load, inhibit bacterial proliferation, and possibly minimize peritoneal adhesions [7]. ...
... The other tissue type is a fenestrated, membranous and translucent layer composed of two mesothelial cell layers wrapping collagen fibres and fibroblast-like cells and not resting on basement membrane (15). The main functions of the omentum as an organ are to store lipids, pool immune cells, adhere to peritoneum to localize inflammation (16,17), regulate fluid exchange in the peritoneal cavity and supply angiogenic and neurogenic factors (18,19). ...
A number of clinical studies have linked adiposity with increased cancer incidence, progression and metastasis, and adipose tissue is now being credited with both systemic and local effects on tumour development and survival. Adipocytes, a major component of benign adipose tissue, represent a significant source of lipids, cytokines and adipokines, and their presence in the tumour microenvironment substantially affects cellular trafficking, signalling and metabolism. Cancers that have a high predisposition to metastasize to the adipocyte-rich host organs are likely to be particularly affected by the presence of adipocytes. Although our understanding of how adipocytes influence tumour progression has grown significantly over the last several years, the mechanisms by which adipocytes regulate the metastatic niche are not well-understood. In this review, we focus on the omentum, a visceral white adipose tissue depot, and the bone, a depot for marrow adipose tissue, as two distinct adipocyte-rich organs that share common characteristic: they are both sites of significant metastatic growth. We highlight major differences in origin and function of each of these adipose depots and reveal potential common characteristics that make them environments that are attractive and conducive to secondary tumour growth. Special attention is given to how omental and marrow adipocytes modulate the tumour microenvironment by promoting angiogenesis, affecting immune cells and altering metabolism to support growth and survival of metastatic cancer cells. © 2016 World Obesity.
Understanding the anatomy and physiology of the peritoneum has a direct effect on the outcome of medical therapy and laparoscopic surgery. The structural organization of the peritoneum, the characteristics of the peritoneal cavity, and the composition and extent of the contained peritoneal fluid pave the path for new discoveries in diagnostic strategies, drug delivery methodologies, and refinement of surgical procedures. The enormous surface area of the peritoneum, and the presence of interconnected greater and lesser peritoneal sacs and recesses in the upper and lower abdomen may render exploration of the extent of cancer dissemination a complicated process, but at the same time present the opportunity to devise effective therapeutic measures that counter inflammatory process and limit dissemination of cancerous cells. Knowledge of the topography, relationships of intra- and retroperitoneal organs, cytoarchitecture of mesothelial cells, and regional variations is likely to enhance focused therapy, reduce postoperative complications, hospital stay, and associated economic cost. Corollary to this, the size, distribution, and the chemical composition of the normal peritoneal fluid allow practitioners to rapidly correlate abnormal findings to disease processes. The nature and site of pain elicited by peritoneal irritation due to localized or generalized pathologic processes may be in the form of a sharp and well-defined or diffuse, dull, and aching pain depending on diseased peritoneal region and stimulated nerves. Hematogenous, lymphatic, or exudative contents of the peritoneal cavity may indicate traumatic injury or inflammatory process that presents rebound tenderness and rigidity.
Maintenance of homeostasis of the peritoneal cavity requires a stable chemical composition of the peritoneal fluid, an optimum temperature, and relative humidity. This way, viscosity of the peritoneal fluid hand and hypothermia are controlled by limiting evaporation and eliminating desiccation. Further, preserving this peritoneal milieu can eliminate cellular inflammation and stress, and reduce pain by blocking the release of immune reactive substances related to cell injury and disruption. In view of the above, preserving moisture on peritoneal surfaces during surgical procedures contributes to a normal physiologic setting and ultimately hastens patient’s recovery.
As one of the important members of reactive oxygen species, ONOO- plays a crucial role in signal transduction, immune response, and other physiological activities. Aberrant changes in ONOO- levels in the living organism are usually associated with many diseases. Therefore, it is important to establish a highly selective and sensitive method for the determination of ONOO- in vivo. Herein, we designed a novel ratio near-infrared fluorescent probe for ONOO- by directly conjugating dicyanoisophorone (DCI) to hydroxyphenyl-quinazolinone (HPQ). Surprisingly, HPQD was unaffected by environmental viscosity and responded rapidly to ONOO- within 40 s. The linear range of ONOO- detection was from 0 μM to 35 μM. Impressively, HPQD did not react with reactive oxygen species and was sensitive to exogenous/endogenous ONOO- in live cells. We also investigated the relationship between ONOO- and ferroptosis and achieved in vivo diagnosis and efficacy evaluation of mice model of LPS-induced inflammation, which showed promising prospects of HPQD in ONOO--related studies.
Peritonitis is a common complication for patients with end‐stage renal disease undergoing peritoneal dialysis (PD) and is a direct cause or contributor in >15% deaths in PD patients. Since early detection is key to treatment, patients and their care teams need rapid, on‐site diagnostics. A hydrogel‐based peritoneal fluid pH sensor attached to a peritoneal dialysis catheter is developed to measure local acidosis indicative of peritoneal infections for early detection and monitoring of infections using X‐ray imaging. The sensor comprises a polyacrylic acid hydrogel with embedded radiopaque markers enclosed in a polymer casing; contraction of the hydrogel in response to acidic pH is evident from the radiographically measured marker position. The sensor has a pH 4–8 response range; between pH 6.5 and 7.5 it responds linearly with a slope of 14% pH 7 length per pH unit, and about 1% length precision. The sensor is attached to a catheter and implanted in a rat peritoneum. Results in awake rats show a rapid pH drop during infection not observed in systemic C‐reactive proteins (CRP) levels nor in the uninfected control animal, with negligible drift over 2 weeks. To our knowledge, this is the first report of an in vivo chemically responsive hydrogel sensor.
El peritoneo: descripción de un nuevo síndrome es el resultado de múltiples cuestionamientos surgidos durante la formación como médicos y cirujanos de los autores, referente a la función del peritoneo en el sentido orgánico específicamente en su aplicación práctica, sin perder de vista el beneficio para los pacientes y de sus familiares.
Background/purpose:
In hepatobiliary and pancreatic (HBP) surgery, the role and significance of intra-abdominal lavage (IAL) for surgical site infection (SSI) is controversial.
Methods:
This prospective study was performed between July 2020 and July 2022. A total of 150 patients, 10-L IAL was performed. The lavage fluid at 1-L, 5-L, and 10-L was subjected to bacterial culture examination. Risk factors for SSI were evaluated.
Results:
Bacterial positivity rate significantly decreased as follows: 1-L, 36% (n=54); 5-L, 27% (n=41); 10-L, 23% (n=35) (36% vs. 23%, P=0.001). Patients with positive lavage fluid culture at 10-L had significantly higher incidence of both incisional (37% vs. 6%, p<0.01) and organ/space (54% vs. 3%, p<0.01) SSI. Multivariate analysis revealed positivity for bacterial culture at 10-L as the strongest independent risk factor for incisional SSI (OR 13.0, 95%CI 3.86-43.6, p<0.01), followed by postoperative pancreatic fistula (OR 11.7, 95%CI 3.03-45.6, P<0.01). Likewise, in organ/space SSI, positivity for bacterial culture at 10-L was the strongest independent risk factor (OR 48.9, 95%CI 12.1-197.7, p<0.01), followed by digestive reconstruction (OR 5.20, 95%CI 1.45-18.6, p=0.01).
Conclusion:
IAL decreased intraperitoneal contamination rate in a volume-dependent manner and can be useful in surveillance of SSI development in HBP surgery.
Objective:
To assess the association between anatomical location of contamination and mortality in dogs with gastrointestinal and biliary origin of septic peritonitis.
Methods:
Medical records at two private referral hospitals between 2003 and 2020 were retrospectively reviewed. Cases were included if the origin of contamination was confirmed intraoperatively within the gastrointestinal or biliary tract. Cases were excluded if the dog died or was euthanized intraoperatively or where the data regarding the origin of contamination were not available. The association of anatomical origin with survival was assessed specifying the locations as stomach, small intestine, large intestine and biliary tract. The gastrointestinal tract origin was further subdivided into pylorus, nonpylorus, duodenum, jejunum, ileum, caecum and colon.
Results:
The overall survival rate was 75.9% (n = 44/58). There were no significant differences in survival among different anatomical origins of contaminations before or after subdivision (P = 0.349 and 0.832, respectively). Also, there was no association between isolated microorganism species in microbiological culture and the anatomical origin (P = 0.951) and the microorganism species was not associated with survival (P = 0.674).
Conclusions:
There was no association between anatomical location of leakage, microorganism species and survival although further studies are warranted to analyse the relationships between anatomical leakage site and microorganism species as well as microorganism species and mortality.
The peritoneal cavity is a fluid-packed area that houses most of the abdominal organs, including the omentum, a visceral adipose tissue with milky patches or groups of leukocytes organized in the same way to those observed in typical lymphoid tissues. A distinct population of leukocytes patrols the peritoneal cavity and travels in and out of the milky spots, facing antigens or pathogens in the peritoneal fluid and responding appropriately. T cells may play a crucial function in regulating adaptive immune responses to antigens in the peritoneal cavity to ensure tissue homeostasis and healing. When peritoneal homeostasis is interrupted by inflammation, infection, obesity, or tumor metastasis, the omentum's dedicated fibroblastic stromal cells and mesothelial cells control peritoneal leukocyte recruitment and activation in unique ways. T cells, which employ their T cell receptor to target specific antigens, are an important component of the acquired immune response since they are present in the peritoneal cavity. The peritoneum provides a different environment for T cells to respond to pathogens. This chapter outlines the anatomy relevant to T cell function and biology, such as antigen processing/presentation, T cell activation, and the many T cell subpopulations in the peritoneal cavity, as well as their role in cancer or other infection.
Background:
Calprotectin is an important molecule in the initiation and progression of the inflammatory process. Systemic and local intraperitoneal inflammation are distinct processes and consequences in peritoneal dialysis (PD). We aimed to evaluate dialysate calprotectin levels and its associations with peritonitis and dialysis adequacy in PD patients.
Methods:
Forty-four PD patients were included in this prospective study. Calprotectin concentration was evaluated in 24-h peritoneal drainage fluid. Patients were followed-up for 1 year, and peritonitis episodes were recorded. Dialysate calprotectin levels were compared to dialysis adequacy parameters and peritonitis frequency.
Results:
The mean age of patients was 54.9±12.7 years. Median PD duration was 54 (23-76) months. Seventeen patients (38.6%) had previous peritonitis episodes. During follow-up, 15 of 44 patients (34.1%) had peritonitis. The median calprotectin concentration was 79.5 (75.2-86.3) ng/ml. The patients were divided into low and high calprotectin groups according to median value. In the high calprotectin group, BMI was found higher (p = 0.04). There was no significant relationship between calprotectin concentration and peritonitis during follow-up (p = 0.29). However, the patients that have had previous peritonitis had higher calprotectin concentrations (p = 0.02). The patients who had higher erythrocyte sedimentation rate (ESR) levels also had higher calprotectin concentrations (p = 0.01).
Conclusion:
Peritoneal calprotectin concentrations were correlated with higher BMI and ESR, and it was higher in patients with previous peritonitis episodes. To our knowledge, this is the first study to examine the peritoneal calprotectin levels in PD patients. Further studies are needed to determine the use of peritoneal calprotectin as an inflammatory marker in PD.
Riassunto
La peritonite secondaria è un’infiammazione acuta del peritoneo conseguente alla perforazione del tratto digerente o alla diffusione di un’infezione intraddominale. Viene fatta una distinzione tra infezioni comunitarie e infezioni associate al trattamento, principalmente postoperatorio. I germi coinvolti sono quelli della flora digestiva, principalmente enterobatteri e anaerobi nelle infezioni comunitarie, ma anche cocchi Gram-positivi, lieviti e bacilli Gram-negativi non fermentanti nelle infezioni associate al trattamento. È spesso complicata da shock settico. Si tratta di un’urgenza diagnostica e terapeutica. Ogni ora persa peggiora la prognosi. La diagnosi è il più delle volte clinica, supportata dallaTC, e può essere difficile da stabilire durante un’infezione postoperatoria. Il trattamento è chirurgico e medico. Il trattamento eziologico si basa su tecniche chirurgiche o interventistiche per identificare ed escludere la causa dell’infezione, prelevare campioni microbiologici, eseguire una toilette peritoneale e prevenire la recidiva. Il trattamento medico supporta le conseguenze dell’infezione mediante rianimazione perioperatoria e trattamento antibiotico probabilistico poi diretto contro i germi isolati nei campioni perioperatori. La terapia antibiotica che non tiene conto di tutti i germi isolati e la gestione tardiva sono fattori di fallimento del trattamento, di persistenza dell’infezione e di morte. La peritonite rimane gravata da un’elevata mortalità, in particolare quando si manifesta in un soggetto anziano con patologie sottostanti, operato tardivamente, soprattutto quando si tratta di un’infezione postoperatoria.
Resumen
La peritonitis secundaria corresponde a una inflamación aguda del peritoneo como consecuencia de una perforación del tubo digestivo o de la extensión de una infección intraabdominal. Se distinguen dos tipos de infecciones: las comunitarias y las asociadas a los cuidados, en su mayoría postoperatorios. Los gérmenes implicados son los de la flora digestiva, principalmente enterobacterias y anaerobios en las infecciones comunitarias, pero también cocos grampositivos, levaduras y bacilos gramnegativos no fermentadores en las infecciones asociadas a cuidados. A menudo se complica con un shock séptico. Se trata de una urgencia diagnóstica y terapéutica, ya que cada hora perdida ensombrece el pronóstico. El diagnóstico suele ser clínico, se confirma mediante tomografía computarizada (TC) pero puede ser difícil de establecer cuando se trata de una infección postoperatoria. El tratamiento es quirúrgico y médico. El tratamiento etiológico está basado en la cirugía o en técnicas intervencionistas para identificar y eliminar la causa de la infección, recoger muestras microbiológicas, realizar una toilette peritoneal y prevenir la recidiva. El tratamiento médico se ocupa de las consecuencias de la infección mediante la reanimación perioperatoria y el tratamiento antibiótico, que primero es probabilista y después específico contra los gérmenes aislados en las muestras perioperatorias. Una antibioticoterapia que no cubra todos los gérmenes aislados y un tratamiento tardío son factores para el fracaso terapéutico, la persistencia de la infección y la muerte. La peritonitis sigue teniendo una elevada mortalidad, sobre todo cuando aparece en el anciano, portador de enfermedades subyacentes, operado tarde, sobre todo cuando se trata de una infección postoperatoria.
Lymphatic vessels have crucial roles in the regulation of interstitial fluids, immune surveillance, and the absorption of dietary fat in the intestine. Lymphatic function is also closely related to the pathogenesis of various disease states such as inflammation, lymphedema, endometriosis, liver dysfunction, and tumor metastasis. Lymphangiogenesis, the formation of new lymphatic vessels from pre-existing lymphatic vessels, is a critical determinant in the above conditions. Although the effect of growth factors on lymphangiogenesis is well-characterized, and biologically active lipids are known to affect smooth muscle contractility and vasoaction, there is accumulating evidence that biologically active lipids are also important inducers of growth factors and cytokines that regulate lymphangiogenesis. This review discusses recent advances in our understanding of biologically active lipids, including arachidonic acid metabolites, sphingosine 1-phosphate, and lysophosphatidic acid, as regulators of lymphangiogenesis, and the emerging importance of the lymphangiogenesis as a therapeutic target.
The goal of postoperative care is the restoration of a woman’s normal physiologic and psychological health. The postoperative period includes the time from the end of the procedure in the operating room until the woman has resumed her normal routine and lifestyle. Postoperative complications may occur at any time; however, early recognition and management will often preclude larger problems. Thus attention to postoperative details cannot be overemphasized. Complications increase the duration of the postoperative stay in the hospital and increase the risk of hospital readmission. Because many procedures are now performed using minimally invasive techniques, patients will usually leave less than or close to 24 hours after surgery, which is often before the signs and symptoms of a complication present. Before discharge, it is important that the patient receive education regarding expectations, signs and symptoms of infection and other complications, and appropriate contact information. Significant risk factors in any surgical population include underlying cardiac and pulmonary disease, smoking, obesity, prior or current abdominal/thoracic surgery, and type of anesthesia. General caveats of postoperative management emphasize attention to the particular needs of each woman. This chapter discusses major issues of management during the period from the end of surgery until the return to normal physiologic and psychological function. However, much of the data regarding postoperative complications only involve the period up through postoperative day 30. Problems and complications arise over the whole spectrum of the postoperative time frame and are interrelated. Thus the clinician must be aware at all times of a woman’s changing status during recovery. For simplicity, this chapter is organized around organ systems and their potential complications.
Objective. To study the lipid peroxidation processes and endogenous intoxication indicators in patients with widespread peritonitis before surgery and during the treatment.
Materials and methods. The study included 97 patients (43 men and 54 women) aged from 17 to 69 years with purulent peritonitis. According to treatment scheme, patients were divided into two groups. Patients in group 1 received standard treatment, and in patients in group 2 standard treatment was supplemented by immunoreactions. The concentration of diene conjugates and malonic dialdehyde, reduced glutathione, catalase activity and the concentration of medium molecular weight peptides were determined in the blood of patients and almost healthy people.
Results. The concentration of diene conjugates, malonic dialdehyde and medium molecular weight peptides in the blood of patients with advanced peritonitis increased significantly depending on the clinical stage of the disease, while the activity of the enzyme catalase and the concentration of reduced glutathione were decreased.
Conclusions. Immunoreactions in combination with standard treatment leads to normalization of lipid peroxidation and reduction of endogenous intoxication on the 5th and 10th days of treatment.
Objective. Comparative studying of the cytokines secretion dynamics in extended purulent peritonitis in postoperative period on background of the standard basic therapy and its combination with cytokinotherapy.
Materials and methods. The levels of anti-inflammatory cytokines IL-2, IL-6, IL-8 and TNF-α in the blood of 97 patients, suffering extended purulent peritonitis of various genesis and various severity degree, were determined. Depending on kind of therapy conducted, the patients were divided into two Groups: the first one - 52 patients, obtaining standard basic therapy and the second - 45 patients, to whom cytokinotherapy was prescribed additionally to standard basic therapy.
Results. In the Group II patients the levels of IL-2, IL-6, IL-8 and TNF-α were raised significantly in reactive phase in 2.1 (p=0.035), 2.4 (p=0.002), 2.0 (p=0.004) and 3.5 (p=0.001) times, accordingly; toxic - in 5.1 (p
Hydrogel coatings have been proposed as a promising strategy to improve the biocompatibility of therapeutic cells and biomedical devices. However, developed coating methods are only applicable for simple geometries, typical sizes, and limited substrates. In addition, its applications in therapeutic cell encapsulation are hampered by inadequate construction of the hydrogel capsules such as off‐center encapsulation, immense volume, and lack of control over the thickness of capsules. Here, a method called surface‐triggered in situ gelation (STIG) for universal hydrogel coating of multiscale objects ranging from single cells to mini‐organs to biomedical devices with arbitrary shapes and heterogeneous components is reported. By covering cells or devices with calcium carbonate particles, progressive propagation of alginate hydrogel from their surface under the stimulation of GDL is achieved. The thickness of the hydrogel layers can be easily controlled from several micrometers to hundreds of micrometers by adjusting the gelation time and the release rate of calcium ions. Importantly, STIG facilitates accurate, complete, and individual cell encapsulation, which potentially overcomes the pitfalls of conventional strategies. It is further proven that the low‐cost and facile method can potentially lead to advances in different fields by rendering precisely controlled microscale alginate layers on a wide variety of biomedical substrates. A simple and facile method is developed for conformal hydrogel coating of living cells, mini‐organs, and biomedical devices. The thickness of the hydrogel layer can be precisely controlled from several to hundreds of micrometers. This method overcomes inevitable challenges in cell encapsulation and enables the engineering of 3D hydrogel for tissue engineering or delivery of therapeutic cells and drugs.
Objective
Thromboxane is an arachidonic acid metabolite that exerts its actions through a G-protein–coupled receptor with 7 transmembrane domains. Although an arachidonic acid metabolite, prostaglandin E2 was reported to enhance lymphangiogenesis, little is known on other arachidonic acid metabolites. In the present study, we investigated the roles of TP (thromboxane prostanoid) signaling in facilitating lymphangiogenesis during inflammation.
Approach and Results
Inflammation was induced by repeated intraperitoneal injections of lipopolysaccharide, and lymphangiogenesis essential for draining peritoneal fluids was estimated in the diaphragm. Lipopolysaccharide induced lymphangiogenesis in the diaphragm in a time-dependent manner in wild-type mice. Compared with wild-type mice, lipopolysaccharide-induced lymphangiogenesis in TP-deficient (TP −/− ) mouse diaphragm tissues was suppressed, and this was accompanied by reduced drainage function from the peritoneal cavity. TP-positive macrophages and T cells were accumulated in the diaphragm and produced VEGF (vascular endothelial growth factor)-C and VEGF-D in a TP-dependent manner. Removal of macrophages and T cells resulted in reduced lymphangiogenesis and lowered expressions of VEGF-C and VEGF-D. Furthermore, TP −/− bone marrow chimeric mice exhibited reduced lymphangiogenesis. TP knockout specific to macrophages and T cells also led to reduced lymphangiogenesis and drainage function in mice with lipopolysaccharide injections.
Conclusions
The present results suggest that TP signaling exerts prolymphangiogenic activity by acting on macrophages and T cells accumulated during inflammation and that TP signaling represents a novel target for controlling lymphangiogenesis.
Internal obturator and/or semitendinosus muscle flaps were used to reinforce primary appositional rectal wall repair in three dogs and one cat in this case series. All three dogs incurred rectal wall compromise during surgical excision of anal sac tumours. The cat sustained bite wounds to the perianal region resulting in abscessation and a rectal tear. Our results indicate that application of an internal obturator and/or semitendinosus muscle flap can reduce the risk of rectal wall dehiscence after primary repair, and consequently the risk of pararectal abscess or rectocutaneous fistula formation.
La situation intrapéritonéale de l’ovaire et la communication établie grâce à la trompe entre le milieu peritoneal et le tractus génital expliquent l’intérêt de la connaissance de la physiologie péritonéale pour la compréhension de la fertilité. Le péritoine, la cavité péritonéale et le liquide qu’elle contient sont des organes originaux dont les rôles physiologiques sont multiples et de ce fait étudiées par des spécialistes très divers: gynécologues, chirurgiens, néphrologues, pneumologues, immunologistes ... Malgré ces travaux très nombreux, la physiologie péritonéale normale reste mal connue du fait de la difficulté, en situation normale, d’accéder à cette cavité profonde.
The peritoneum is composed of a layer of polyhedral-shaped squamous cells approximately 3 mm thick and may be viewed anatomically as a closed sac that allows for the free movement of abdominal viscera.1 Adherent to the anterior and lateral abdominal walls, the peritoneum invests the intraabdominal viscera in such a way as to form the mesentery for the small and large bowel, a peritoneal diverticulum posterior to the stomach (the lesser sac) and a number of spaces or recesses in which blood, fluid, or pus can localize in response to various disease processes (Fig. 24.1).
Les péritonites sont des infections aiguës de la cavité péritonéale le plus souvent d’origine bactérienne et/ou fongique. Le propos de ce chapitre est de traiter des péritonites non postopératoires en détaillant leurs spécificités étiologiques, diagnostiques et thérapeutiques. La principale classification nosologique utilisée actuellement pour décrire les péritonites est la classification de Hambourg (tableau I) [1].
The polysaccharide capsule of Bacteroides fragilis has been shown to be important in the virulence of the organism. The capsular polysaccharide (CP) of B. fragilis has been extensively purified. Using a murine model of intraabdominal abscess formation, we have been able to demonstrate cellular immunity to the capsular polysaccharide of B. fragilis. Immunization of C57BL/10J mice with the CP over 5 wk prevents abscess formation when the mice are challenged with B. fragilis intraperitoneally. This immunity can be transferred to naive mice with spleen cells from immune animals. The immune cells bear Thy-1.2 and Ly-2.2 antigens. The immune response has been shown to be antigen specific, but not H-2 restricted. The possibility that these immune cells are suppressor T cells is discussed. The experimental system presented provides a model for the examination of the cellular interactions responsible for abscess formation and the cellular response to bacterial pathogens.
The Omentum explores and assesses the comparatively new approach of using omental attachment in the treatment of a variety of neurologic diseases. Topics discussed include historical images and ideas connected with the greater omentum; angiogenesis and the greater omentum; implications for central nervous system injury of vasoactive chemicals in the omentum; effects of omental-derived lipid fractions on osseous vascularization and bone formation; cerebral revascularization by omental graft for moyamoya disease; omental transposition for treating the sequelae of viral encephalitis; experimental and clinical use of omental transposition for spinal cord pathology; and lumbo-omental shunt for treatment of communicating hydrocephalus. The effect of omentum transposition to the brain on regional cerebral blood flow in stroke patients and on delivery of chemotherapeutic agents to malignant brain tumors is also considered.
Objective:
To examine the effects of a nitric oxide synthase inhibitor on host elimination of bacteria, tumor necrosis factor (TNF) production, and survival in a murine sepsis model.
Design:
Prospective randomized experimental trials.
Setting:
Laboratory.
Materials:
Female Balb/c mice.
Interventions:
Balb/c mice were injected with Escherichia coli (108 colony-forming units per body) into the peritoneal cavity. N-ω-Nitro-l-arginine-methyl-ester (l-NAME), an inhibitor of nitric oxide synthase, was given intraperitoneally at 10 mg/kg (N10 group) or 100 mg/kg (N100 group) 1 hour before bacterial challenge.
Main Outcome Measures:
Thirty animals were observed for survival. Samples of peritoneal lavaged fluid (PLF), blood, liver, and lungs were obtained at 4 and 6 hours after bacterial challenge (n=60). The peritoneal exudative cells were counted. Viable bacterial counts were determined in PLF, blood, and organs. The TNF levels also were determined in plasma, PLF, and supernatant samples of cultured peritoneal exudative cells.
Results:
Survival times after E coli challenge were significantly reduced by pretreatment with l-NAME (100 mg/kg intraperitoneally). Numbers of viable bacteria in the peritoneal cavity and plasma TNF level 4 hours after E coli challenge were higher in both l-NAME–treated groups than in the control group. The number of bacteria in the blood and the plasma TNF level 6 hours after E coli challenge were higher in the l-NAME–treated group (N100 group) than in the control group. Conversely, the number of hepatic bacteria in the control group was significantly higher than in the l-NAME–treated groups. Plasma TNF level showed significant positive correlations with numbers of bacteria in the PLF and in the blood 4 hours after challenge. No significant differences were noted in TNF levels in PLF and peritoneal exudative cell cultured supernatants.
Conclusion:
Inhibition of nitric oxide production is detrimental in this gram-negative sepsis model.(Arch Surg. 1995;130:410-414)
• Sterile and endotoxin-free biomaterials commonly used in prosthetic devices (Dacron velour, woven Dacron, and Biomer polyurethane) and cotton (control material) were implanted intraperitoneally in mice with normal enteric flora. Intraperitoneal Biomer and woven Dacron became contaminated with 100 to 10 000 enteric bacteria, including Escherichia coli, Pseudomonas aeruginosa, enterococci, and staphylococci species, within 3 days; intraperitoneal cotton and Dacron velour were contaminated within 24 hours. Mesenteric lymph nodes showed parallel incidences of translocation. The peritoneal cavity became contaminated only if the biomaterial itself became contaminated. No bacterial overgrowth, perforation, or histologic changes in the bowel were found. Subcutaneous biomaterials remained sterile. Ingested fluorescent beads appeared in enterocytes, in lamina propria within macrophages, and in intraperitoneal biomaterials. The data suggest that intraperitoneal sterile reactive stimuli can induce bacterial translocation to the dense prosthesis directly through the intact normal bowel wall. One of the mechanisms seems to involve phagocytosis of particles and bacteria within the bowel wall that are then chemotactically attracted to nearby sites of inflammation.
(Arch Surg. 1991;126:157-163)
Objectives:
To test the hypothesis that pretreatment with radiodetoxified endotoxin (RDE) may mitigate the deleterious effects of subsequent infection, in part by modifying leukocyte adhesion receptor expression, and to investigate the cellular mechanisms of endotoxin tolerance induced by RDE.Design:
To assess the effect of RDE pretreatment on mortality from bacterial peritonitis, rats were implanted with an intraperitoneal, barium-fecal inoculum at intervals of 0,1, 3, and 5 days after RDE injection. Experiments were then conducted to test the effect on leukocyte adhesion receptor expression. Two groups of mice received saline solution, and one group, RDE. After 72 hours, one group received saline solution (saline/saline group), the others, lipopolysaccharide (LPS) (saline/LPS and RDE/LPS groups). Peripheral leukocytes were obtained 1 hour after injection and were analyzed for CD11b and CD18 expression by flow cytometry.Setting:
Laboratory animal study.Results:
Survival rates were not improved in rats that were pretreated with RDE 0 and 24 hours before inoculum (0% and 7%, respectively). In rats that were pretreated 72 hours and 120 hours before inoculum, 47% (P<.01) and 60% (P<.01) survived, respectively. CD18 expression on polymorphonuclear leukocytes increased twofold in the RDE/LPS (mean±SEM, 300.3±32.9) and the saline/LPS (mean±SEM, 360.4±59.9) groups compared with controls (mean±SEM, 176.4±18.9) (P<.05). CD1 lb expression on polymorphonuclear leukocytes increased three-fold in the RDE/LPS (mean±SEM, 91.3±8.1) and the saline/LPS (mean±SEM, 89.8±11.4) groups compared with controls(mean±SEM,32.1 ±1.8) (P<.05). CD18 expression on monocytes decreased in the saline/LPS group (mean±SEM, 134.2±14.2) and was unchanged in the RDE/LPS group (mean±SEM, 200.2± 17.2) compared with controls (mean±SEM, 217.6±16.5) (P<.05). CD11b expression on monocytes decreased in the saline/LPS group (mean±SEM, 25.8±2.2) and was unchanged in the RDE/LPS group (mean±SEM, 36.4±0.9) compared with controls (mean±SEM, 39.7±3.9) (P<.05).Conclusions:
Radiodetoxified endotoxin reduces mortality rates from bacterial peritonitis when given at least 72 hours prior to a bacterial inoculum. Tolerance to subsequent LPS challenge is associated with an abrogation of the reduced peripheral monocyte CD11b and CD 18 expression observed in native LPS-stimulated mice but is not associated with changes in polymorphonuclear leukocyte CD 11b and CD 18 expression. The mechanism of the observed RDE-induced monocyte hyporesponsiveness to LPS and its possible protective effect is uncertain and requires further investigation.(Arch Surg. 1994;129:1153-1158)
Intestinal dysfunction commonly occurs following hemorrhage and injury and appears to contribute to the development of multiple organ system failure in this setting. In order to examine possible mechanisms leading to intestinal dysfunction following blood loss, we investigated mRNA levels for cytokines with proinflammatory and immunoregulatory properties (interleukin 1beta (IL-1beta), IL-6, IL-10, TNF-alpha, TGF-beta, IFN-gamma) as well as mRNA expression for inducible nitric oxide synthase (NOS) over the 3 days following hemorrhage and resuscitation. Significantly increased levels of mRNA for IL-1beta, IL-10, and IFN-gamma were found among cells isolated from Peyer's patches 3 days following hemorrhage. Amounts of mRNA for inducible NOS were not significantly altered 24 or 72 h after blood loss. In addition to being increased 72 h following hemorrhage, levels of mRNA for IL-10 also were increased 1 and 4 h posthemorrhage. No alterations in cytokine or NOS expression were found 24 h following blood loss. These results demonstrate that significant increases in proinflammatory and immunoregulatory cytokine mRNA levels among cellular populations in Peyer's patches are present at late posthemorrhage time points. These alterations in cytokine expression may contribute to the morphologic, immunologic, and functional changes in the intestines which are present following blood loss and injury.
We studied the toxicity of free radicals to human mesothelial cells in vitro and to the peritoneal membrane of rats during peritoneal dialysis. Free radicals cause damage to mesothelial cells as measured by release of cytosolic markers such as 86Rb and lactate dehydrogenase. Vitamin E neutralized the toxic effect of free radicals in vitro. Human mesothelial cells exposed over 6 h to a mixture of essential and nonessential amino acids in medium are more vulnerable to the cytotoxic effect of free radicals than control cells exposed to medium alone. Cells exposed previously to glucose or glycerol are less vulnerable than controls. In rats free radicals generated intraperitoneally by a xanthine-xanthine oxidase system induce changes in peritoneal permeability similar to those observed during peritonitis: loss of ultrafiltration, increased glucose absorption from the dialysate and augmented transperitoneal loss of albumin. In addition lipids in the peritoneum became perixodated. The addition of vitamin E to the peritoneal fluid with xanthine-xanthine oxidase prevents peroxidation of lipids and the subsequent loss of ultrafiltration. Our results show that free radicals may exert a potentially toxic effect on the peritoneal membrane during peritonitis. In such circumstances the addition of free radical scavenger to the dialysis fluid may preserve intact structure and function of peritoneum.
Normal human mesothelial cells (NHMC) were isolated from pieces of human omentum. The cell yield was approximately one million
cells per square centimeter omentum. The mesothelial cells were identified by their positive staining with monoclonal antibodies
against cytokeratins 6 and 18. Transmission electronmicroscopy of cultured NHMC revealed many microvilli on the apical surface
and many mitochondria and pinocytotic vesicles in the cytoplasm, indicating active transmembrane transport. Growth of NHMC
was directly related to the concentration of human serum or of fetal bovine serum in the growth medium. Addition of epidermal
growth factor with or without hydrocortisone resulted in a significant increase of NHMC growth; when endothelial cell growth
factor, insulin, or hydrocortisone were added no such increase was observed. Seeding NHMC at densities less than 3000/cm2 did not result in monolayer formation. The mesothelial cells were serially passed in growth medium M199 with added 10% fetal
bovine serum up to 7 passages. However, after Passage 4 the cells changed into giant cells with an irregular pattern, and
a lack of intracellular cytokeratin expression was observed for most of the cells.
The complement system has evolved to fulfil crucial functions, including opsonization of micro-organisms, enhancement of inflammatory responses, clearance of immune complexes and cell lysis. Deficiencies or dysregulations of this system are associated with major health burdens, such as infectious and autoimmune diseases. A recent meeting* addressed the function and role of complement, and its regulators, in human disease.
Intraperitoneal oxygen and carbon dioxide tensions were studied in rats during silica-induced adhesion formation or fecal peritonitis. Measurements of PO2 and PCO2 in the abdominal cavity were performed by means of an implanted Silastic tonometer. During active adhesion formation one to three weeks after administration of silica, the intra-abdominal PO2 decreased by 50 per cent from normal whereas the intra-abdominal PCO2 and the rate of oxygen consumption in the peritoneum were elevated. Progressing peritonitis also resulted in decreased intraperitoneal PO2 and increased accumulation of carbon dioxide in the peritoneal cavity. In rats with peritonitis the rate of oxygen consumption in the peritoneal exudate clearly exceeded that in the peritoneal membrane.
Sprague-Dawley rats were injected intraperitoneally with an inoculum of living or killed E. Coli suspended in a solution with or without hemoglobin. Rat mortality rate was directly proportional to both the number of viable bacteria and the amount of hemoglobin injected, though sterile hemoglobin was innocuous. Serial bacterial colony counts, white blood cell counts, and differential stains of the peritoneal fluid revealed that (1) hemoglobin significantly inhibited the intraperitoneal influx of white cells (especially polymorphonuclear leukocytes [PMNs]) in response to an intraperitoneal bacterial challenge; (2) hemoglobin inhibited bacterial clearance from the peritoneal cavity; (3) both the rate of clearance from and the rate of PMN influx into the peritoneal cavity were inversely proportional to the hemoglobin concentration; (4) hemoglobin reversed both the process of peritoneal leukocytosis and the clearance of bacteria from the peritoneal cavity when injected 90 minutes after the bacteria; (5) the suppressive effect of hemoglobin on peritoneal leukocytosis did not depend on bacterial viability. The results strongly suggest that hemoglobin interferes with the response of PMNs to chemotactic stimuli normally produced after bacterial challenge in the peritoneal cavity. Thus the adjuvant effect of hemoglobin in experimental peritonitis appears to be based on its interference with the influx of PMNs into the peritoneal cavity in response to bacterial organisms. Thus the organisms are relieved of the principal antibacterial defense in the peritoneal cavity and are permitted uncontrolled proliferation.
Three injections of intraperiotoneal (IP) zymosan-induced profound resistance to E. coli peritonitis in Sprague-Dawley rats. IP zymosan had minimal effects on organ weights and systemic phagocytic clearance ability, suggesting that this mode of administration had few systemic reticuloendothelial system (RES) effects. Hemoglobin (a known inhibitor of local phagocytosis) reduced the protection induced by zymosan, giving further evidence that IP zymosan acts locally. IP zymosan stimulation results in an initial marked influx of polymorphonuclear cells followed by a greater percentage replacement of mononuclear cells by the third day. Examination of these cells via chemiluminescence studies demonstrated that the phagocytic capacity of zymosan-stimulated peritoneal cells was markedly greater than the control group on a cell-for-cell basis. IP zymosan also gave some protection against intravenous (IV) E. coli, but IV zymosan did not significanly protect against IP E. coli. Possible mechanisms of action are discussed. These findings suggest that a technique of local RES stimulation could have a place in preparation of certain high-risk patients for elective abdominal surgery where peritoneal contamination is likely.
The local action of bile salts has been associated with a wide variety of gastrointestinal diseases. This paper describes an animal model to determine which of the major solid components of bile are responsible for peritoneal destruction in biliary peritonitis. In the rat, bile salts within the peritoneal cavity cause peritonitis but cholesterol and lecithin are without deleterious effect.
Surgical trauma to the peritoneum, in the absence of infection, elicits a rapid and transient influx of polymorphonuclear leukocytes (PMNs) into the peritoneal cavity prior to the accumulation of macrophages. The aim of this study was to characterize the effects of these PMNs on macrophage function in the early postsurgical period. Rabbits underwent intestinal reanastomosis and peritoneal exudate cells were collected at various times after surgery. Macrophage-enriched preparations were incubated with spent media from cultures of PMNs obtained at the corresponding times after surgery. Superoxide anion (O2-) release by macrophages in response to phorbol myristate acetate was determined by cytochrome c reduction. Fibrinolytic and protease inhibitory activities in macrophage-spent media were also evaluated. The release of O2- had already increased at 2 hr, reached peak levels at 6 hr, and decreased by 24 hr after surgery. Spent media from PMNs harvested 6 hr after surgery suppressed, whereas spent media from postsurgical 12- or 24-hr PMNs increased O2- release from macrophages harvested at 6 and 12 hr after surgery. PMN-spent media had no effect on the secretion of plasminogen activator (PA) from macrophages harvested within 12 hr after surgery. In contrast, PA activity in the spent media from macrophages harvested 24 hr after surgery was elevated after exposure to PMN-spent media. PA inhibitory activity was reduced in macrophage-spent media at 2 hr after surgery and increased by 24 hr, while PMN-spent media had no effect on the level of PA inhibitory activity. Thus, soluble factors secreted into the culture medium by PMNs modulate macrophage function as soon as 6-12 hr after surgery.
Silicone elastomers used to make medical implants and prostheses are generally believed to be biologically inert. However, we have seen two patients who showed severe, apparently immunemediated, reactions to ventriculoperitoneal (VP) shunts. We used an enzyme-linked immunosorbent assay in which Silastic tubing served as the solid-phase antigen to test serum from the two patients, five other VP shunt patients without inflammatory reactions, and nine healthy adults. IgG binding to Silastic tubing was consistently higher in the two patients than in the healthy or patient controls. The IgG seemed to be binding specifically, since IgG Fab fragments also bound to the tubing, and preincubation of serum with Silastic or silylated proteins removed most of the activity. These findings show that specific immune reactivity to elastomers of polydimethylsiloxane can develop in human beings.
Omental milky spots are omentum-associated lymphoid tissues that cede peritoneal macrophages and participate in the immunity of the peritoneal cavity. We studied the changing surface features of milky spots and milky spot macrophages of Wistar rats, following the i.p. administration of OK-432, a killed streptococcal preparation (1 Klinische Einheit (unit) in 5 ml of phosphate-buffered saline) by the use of scanning electron microscopy. OK-432-activated macrophages demonstrated marked surface membrane activity and migrated through the stomata of the milky spot into the peritoneal cavity. The characteristic features of activated milky spots and milky spot macrophages were noted as early as 3 h following the administration of OK-432, and continued to be observed until 7 days after the injection. By 14 days after the injection, the structural integrity of the milky spot was partially lost. The activation of milky spots and milky spot macrophages by OK-432 provides a convenient in vivo system for the monitoring and study of i.p. cellular events.
The author has substantiated a concept that in the general notion of the impermeability of intestinal sutures, it is necessary to distinguish between physical impermeability (imperviousness of sutures to liquids and gases) and biologic impermeability (imperviousness of sutures to microbes and toxins). It was established in experiments on 165 dogs that infection that invaded peritoneum during operation disappeared from the peritoneal cavity within an hour of small-bowel and stomach surgery and within 1 1/2 hours of colon surgery. Then a period of sterility of peritoneum was observed, which lasted for 8 to 9 hours after operations on the stomach and the small bowel (p = 0.01) and for 4 to 7 hours after operations on the colon (p = 0.01). In the following hours the peritoneal cavity was infected through physically hermetic intestinal sutures. At the end of 24 hours the peritoneum of operated organs showed the presence of 10(4) to 10(6) intestinal microbes. Greater omentum, bowel loops, and their mesentery adhered to the suture in response to the infection through the suture. Complete covering of the suture with adjacent viscera prevented infection of the peritoneal cavity through the suture. The author suggests a well-grounded concept of the leading role of infection through a physically hermetic intestinal suture in the development of postoperative peritonitis and peritoneal adhesions.
During generalized immune complex-induced inflammation of the peritoneal cavity, two peaks of tumor necrosis factor (TNF)
were observed in the peritoneal exudate of normal mice. In mast cell-deficient mice, the first peak was undetected, and the
second peak of TNF and neutrophil influx were significantly reduced. Antibody to TNF significantly inhibited neutrophil infiltration
in normal but not in mast cell-deficient mice. Mast cell repletion of the latter normalized TNF, neutrophil mobilization,
and the effect of the antibody to TNF. Thus, in vivo, mast cells produce the TNF that augments neutrophil emigration.
In the milky spots, precursors of cells belonging to the mononuclear phagocyte system (MPS), such as monoblasts, can be found on the basis of ultrastructural endogenous peroxidase cytochemistry. Therefore, in the present study, we investigated the milky spots using a panel of monoclonal antibodies, especially antibodies (ER-MP) that recognize macrophage precursor antigens. Early macrophage precursor antigens ER-MP12 and ER-MP58 were detected only on cells localized inside the milky spots. On the other hand, an antigen which disappears late in the course of macrophage differentiation, ER-MP20, was detected in high amounts on cells both inside and around the milky spots. This clearly indicates that macrophage precursors are centrally localized inside the milky spots, while more differentiated cells are found in peripheral areas. Moreover, long-term culture of milky spot tissue resulted in the forming of a monolayer of stromal cells which supported macrophage proliferation in vitro. In conclusion, both in situ and in vitro studies demonstrated that mouse milky spots have a microenvironment in which precursor cells of the MPS can home and proliferate, illustrating that milky spots play a role as a source of local macrophage generation, e.g. that of the free peritoneal macrophages.
Surgical trauma induces immunosuppression that may adversely influence survival. This study examined the effect of laparotomy on two different macrophage populations, peritoneal macrophages (PM phi) and Kupffer cells. Female, 6- to 8-week old, CFW/C3H-HeN mice (n = 160) were randomly allocated to one of three study groups: control, ether anesthetic only, or ether anesthetic and laparotomy. On postoperative days 1 and 3, PM phis and Kupffer cells were harvested and assayed for superoxide anion production (O2-), percent macrophage phagocytosis of Candida albicans (CAP), percent C. albicans killed by macrophages (CAK), percent major histocompatibility complex (MHC)-class II antigen expression, and antigen presentation. Macrophages isolated on postoperative day 1 were also cocultured with 100 units/10(6) cells/ml interferon-gamma (IFN-gamma). Laparotomy significantly impaired microbicidal activity (O2-, percent CAP, and percent CAK) and antigen presentation on postoperative day 1. On postoperative day 3, O2- and antigen presentation were increased significantly (p less than 0.05) over control values, indicating a rebound phenomenon. Kupffer cell microbicidal function was unchanged on postoperative days 1 and 3. The initial immune impairment (PM phis: O2-, CAP, and CAK) was abrogated by IFN-gamma treatment. In immunosuppressed hosts after injury, administration of macrophage-activating factors such as IFN-gamma could be of therapeutic benefit.
It is suggested that omental milky spots in young children, which in later life gradually transform into fatty tissue and only reappear during intraperitoneal infection, might influence the development of gastrointestinal immunity.
To test whether bile acids interact with mast cells, dilute, aqueous solutions of five pure unconjugated natural bile acids and their corresponding glycine or taurine conjugates were incubated with murine PT-18 cells (a mast cell line functionally and cytochemically similar to mucosal mast cells) or with freshly isolated rat peritoneal mast cells. Bile acid solutions ranged in concentration from 0.3 to 10 mmol/L; histamine release was assessed by a fluorimetric assay, and cell lysis by cytosolic enzyme (lactate dehydrogenase) release. Lipophilic, dihydroxy bile acids (chenodeoxycholic acid and deoxycholic acid as well as their glycine and taurine conjugates) caused histamine release in a dose-related manner; cholic acid and its conjugates caused much less or no histamine release. Two hydrophilic bile acids (ursodeoxycholic acid and ursocholic acid and their conjugates) were virtually devoid of activity. Histamine release, which was independent of extracellular Ca2+, occurred at 0.3 mmol/L, well below the critical micellization concentration. For a given concentration, unconjugated bile acids and glycine-conjugated bile acids induced more histamine release than taurine-conjugated bile acids; maximal release was observed at 3 mmol/L for lipophilic, dihydroxy bile acids. To test whether bile acids could also cause histamine release from cutaneous mast cells in vivo, rats were injected intradermally with bile acid solutions and histamine release assessed by capillary leakage of Evan's blue dye. Cutaneous blueing was greater with cytotoxic bile acids, chenodeoxycholyglycine or deoxycholylglycine, than with ursodeoxycholylglycine and was inhibited by prior antihistamine treatment. Histamine release correlated highly and positively with lipophilicity and with bile acid surface activity. It was concluded that lipophilic but not hydrophilic bile acids possess concentration-dependent cytotoxicity toward mast cells causing histamine release, that unconjugated and glycine-conjugated bile acids are more potent than taurine-conjugated bile acids, and that mast cell histamine release is highly correlated with lipophilicity of bile acids as well as their surface activity.
The mesothelial cells obtained from human omental adipose tissue showed a typical cobblestone monolayer and reacted strongly with keratin, but did not have Von Willebrand factor. Ultrastructurally these cells revealed the existence of desmosome-like cell junctions as well as intracellular canaliculi, tubular structures surrounded by microvilli, and tonofilament-like filaments.
The mesothelial cells grew much faster in the medium containing epidermal growth factor, actively took up acetylated-low density lipoprotein into their cytoplasm, and released angiotensin-converting enzyme. They also released urokinase-type plasminogen activator, but only half as much as do human umbilical vein endothelial cells; release of tissue-type plasminogen activator was not observed. Inasmuch as the mesothelial cells also released plasminogen activator inhibitor-1, as do human umbilical vein endothelial cells, we could not detect u-PA activity in culture medium. u-PA may play a role in the protection against adhesion among visceral organs. These observations indicate that cultured human mesothelial cells have characteristics closely related to those found in human endothelial cells.
Rat peritoneal polymorphonuclear leukocytes (PMN) elicited with oyster glycogen contain a Ca2+-independent nitric oxide (NO) synthase which is induced in vivo in a time-dependent manner. When washed PMN containing low levels of enzyme activity were cultured ex vivo further expression of NO synthase was observed. This was inhibited by cycloheximide indicating that de novo synthesis of the enzyme occurred during the ex vivo incubation. Enzyme activity was enhanced by interferon (IFN)-γ, but not by tumor necrosis factor (TNF)-α when added ex vivo. However, IFN-γ and TNF-α synergized to increase further the expression of NO synthase.
Treatment of rats with dexamethasone inhibited the induction of NO synthase in elicited PMN. This treatment reduced the accumulation of PMN by approximately 30%, without affecting cell viability. Dexamethasone also inhibited the induction of the NO synthase ex vivo in a concentration-dependent manner. Furthermore, the enhanced enzyme activity following treatment of PMN with cytokines was also inhibited by dexamethasone. Once induced, dexamethasone did not affect enzyme activity. These data indicate that PMN elicited in the rat peritoneum with oyster glycogen express an NO synthase in vivo and ex vivo. The induction of the enzyme can be further stimulated ex vivo with IFN-γ and TNF-α and inhibited by dexamethasone. The inhibition of the induction of NO synthase in the PMN by dexamethasone may contribute to the anti-inflammatory activity of this and other glucocorticoids.
Here, Charles Janeway argues that the requirement for two signals to initiate the adaptive immune response may reflect the evolutionary history of host defences. Early phases of host defence involve receptors and ligands that may have controlled immune responses prior to the development of clonally-distributed receptors encoded in rearranging genes. The former receptors persist in contemporary vertebrates both to trigger innate or nonclonal responses and to signal to lymphocytes that a particular antigen is associated with a microorganism.
Up to our century, the surgical approach to the greater omentum was mainly confined to resectional techniques of the prolapsed organ following abdominal injuries. The present contribution highlights the early searches for the nature of the greater omentum in the discovery of an organ which has for so long been disregarded, but now attracts increasing consideration as useful plastic material in surgery. This structure, used at various sites of the body to repair defects and provide blood supply, also opened new clinical and experimental fields of both surgical and immunological aspects.
Sterile and endotoxin-free biomaterials commonly used in prosthetic devices (Dacron velour, woven Dacron, and Biomer polyurethane) and cotton (control material) were implanted intraperitoneally in mice with normal enteric flora. Intraperitoneal Biomer and woven Dacron became contaminated with 100 to 10,000 enteric bacteria, including Escherichia coli, Pseudomonas aeruginosa, enterococci, and staphylococci species, within 3 days; intraperitoneal cotton and Dacron velour were contaminated within 24 hours. Mesenteric lymph nodes showed parallel incidences of translocation. The peritoneal cavity became contaminated only if the biomaterial itself became contaminated. No bacterial overgrowth, perforation, or histologic changes in the bowel were found. Subcutaneous biomaterials remained sterile. Ingested fluorescent beads appeared in enterocytes, in lamina propria within macrophages, and in intraperitoneal biomaterials. The data suggest that intraperitoneal sterile reactive stimuli can induce bacterial translocation to the dense prosthesis directly through the intact normal bowel wall. One of the mechanisms seems to involve phagocytosis of particles and bacteria within the bowel wall that are then chemotactically attracted to nearby sites of inflammation.
A surgical aphorism has long held that the omentum is the "watchdog of the abdomen." However, detractors believe that leaving the omentum behind after colectomy precipitates later small bowel obstruction. A retrospective comparison was made between a group of 406 patients (Group I) having omentectomy with proctocolectomy and ileoanal anastomosis and a group of 239 patients (Group II) having a similar procedure without omentectomy. Follow-up in this series of 645 patients was 4.3 +/- 2.1 years (mean +/- SEM). No difference was present in the rate of partial small bowel obstruction or complete small bowel obstruction between Group I patients (32 percent partial, 12 percent complete) and Group II patients (29 percent partial, 12 percent complete; P greater than 0.1). However, a better outcome with regard to postoperative sepsis and sepsis requiring operation was apparent in Group II patients retaining the omentum (4 percent and 3 percent, respectively) than in Group I patients (10 percent and 8 percent, respectively), in whom the omentum was removed (P less than 0.01). As this experience would support, we urge surgeons to "let sleeping dogs lie" and, when possible, retain the omentum when performing colectomy or proctocolectomy.
The mechanisms leading to reduction of peritoneal fibrinolytic activity in conditions that are associated with the formation of intra-abdominal adhesions were studied. Tissue plasminogen activator was found, by antibody inhibition techniques, to be the activator of fibrinolysis in homogenates of control peritoneum (n = 6). Homogenates of control (n = 10) and inflamed peritoneum (n = 10) were analysed. Plasminogen activating activity was much lower in inflamed peritoneum (median 0.07 IU/cm2) than in control tissue (median 12.0 IU/cm2) (p less than 0.001). Levels of tissue plasminogen activator and alpha 2-antiplasmin were similar in both control and inflamed tissue. Plasminogen activator inhibitor-1, not detectable in control peritoneum, was present in inflamed tissue and might be the reason for the reduction in functional fibrinolytic activity.
Intraabdominal infections are a major source of morbidity and mortality for the trauma and postoperative patient. Transient
peritoneal contamination with bacteria after either intentional or unintentional violation of the gut are common. The effect
of this intermittent antigen exposure upon later formation of intraabdominal abscesses is unclear. Previous experiments by
others have demonstrated that repeated exposure to Bacteroides fragilis capsular polysaccharide can induce a T lymphocyte-mediated immunity to subsequent induction of pure B. fragilis abscess formation. In a murine mixed intraabdominal abscess model, preexposure to live Escherichia coli, B. fragilis, or both increased the number of later abscesses and in some cases their bacterial composition. Further, immunization with
E. coli alone increased late mortality without altering overall mortality. These data suggest that the alterations of immune function
produced by live, transient bacteria upon subsequent mixed intraabdominal abscess induction resultin fundamentally different
consequences from those observed after specific polysaccharide antigen exposure and subsequent monomicrobial abscess induction.
The serotypes of 474 clinically significant Streptococcus pneumoniae respiratory isolates collected during a national surveillance study in 1987–1988 were compared to the capsular types included
in the 23-valent pneumococcal polysaccharide vaccine licensed for use in the United States. Overall, 355 isolates (74.9%)
belonged to types included in the current vaccine, while another 65 (13.7%) were types serologically related to vaccine types
and likely to be protective by virtue of cross-reactivity. Relatively few isolates (9.1%) belonged to nonvaccine serotypes,
and only 2.3% were nontypable. The mucoid serotype 3 was most frequent (13.1% of total), followed by 19F(9.3%), 23F (7.4%),
6 Band 14(5.7% each), and 4 and 6A(5.5%each). The most frequent type not included in the vaccinewas type 16 (2.1% of all isolates).
Thus, nearly 89% of respiratory isolates included in this study were encompassed within the antigenic spectrum of the currently
marketed pneumococcal vaccine.
We studied prospectively the ascitic fluid of 47 patients. Thirty-five were cirrhotics (group A) and 12 had malignant peritonitis (group B). All ascitic fluid samples were initially uninfected. We measured opsonic activity by a chemiluminescent assay, and chemoattractant activity by the under agarose technique. We also measured ascitic concentrations of C3, C4, fibronectin, C-reactive protein, immunoglobulins G, A and M and total proteins. All patients were followed throughout the presence of ascites. None of the group B patients developed peritoneal infection, nor did 23 of the group A patients (group A2). Twelve group A patients (group A1) developed spontaneous bacterial peritonitis (SBP), four of them with recurrence. All indices except immunoglobulins A and M were significantly different between group A and group B patients. Comparing group A1 and group A2, only chemoattractant activity and concentrations of total proteins and C3 were significantly lower in group A1. Using a multivariate analysis with Cox's model, only C3 concentration had an independent predictive value for occurrence of SBP in cirrhotic patients.
There were 3 cases of Fitz-Hugh-Curtis syndrome,--pelvic inflammatory disease (PID) complications and perihepatitis,--caused by Chlamydia trachomatis infection. All 3 patients complained of sudden right upper quadrant pain in addition to PID symptoms. Enzyme immunoassay of uterine cervical specimens revealed that the positive chlamydial antigen and serum antibody titer against anti-Chlamydia trachomatis were also high. In all cases the laparoscopy revealed findings of perihepatitis on the anterior surface of the right hepatic lobe. In 2 cases, typical violin-string adhesions were also observed between the liver capsule and parietal peritoneum. In both cases, adhesiolysis was conducted during the laparoscopy.
Rat omental dendritic cells (ODC) occur in two forms, mainly spindle-shaped, Ia-, on the surface, and stellar, Ia+ within the omentum. Like macrophages, most ODC label with W3/25 mAb and have a demonstrable activity of non-specific esterase, acid phosphatase and ATPase. Up to 30% of ODC are actively phagocytic. The proportion of Ia+ ODC rises 7 days after ip antigenic stimulation and there seems to be a reciprocal development of Ia positivity and phagocytic capacity between ODC and macrophages 3 and 5 days after ip immunization. ODC contribute to the overall fluctuation of Ia expression in the entire omentum after immunization. Ia+ ODC display a linear arrangement along preilymphatic spaces and may be related to the formation of new lymph vessels. They also constitute the stroma of pseudofollicles containing clusters of what are presumably T-helper lymphocytes closely attached to ODC, scattered suppressor T lymphocytes and B cells accumulating in later stages at the immune response.
To investigate whether bile within the abdominal cavity changes the morphologic expression of peritonitis, rats received intraperitoneal injections of saline, bile, Escherichia coli (3 x 10(8) colony-forming units), or E. coli and bile (n = 10 in each group). Specimens were taken from the parietal and visceral peritoneum for light microscopy and scanning electron microscopy, 10 h after induction of peritonitis. Bile alone increased the number of inflammatory cells, especially of the monocytic type. After E. coli alone the monocytic cell response was less pronounced, whereas the polymorphonuclear leukocyte response was comparatively large in the visceral peritoneum. Addition of bile in E. coli peritonitis caused a substantial increase in polymorphonuclear leukocytes, especially in the visceral peritoneum, and in the depth of the inflammatory cell reaction. At scanning electron microscopy mesothelial cells appeared normal after bile alone, had reduced numbers of microvilli after E. coli alone, and were denuded or separated, without microvilli, after E. coli and bile. It is concluded that the inflammatory effects of E. coli are greatly enhanced in the presence of bile.
Peritoneal mast cells (PMC) and intestinal mucosal mast cells (IMMC) were purified from rats infected with the nematode Nippostrongylus brasiliensis. Overall protein constituents of both mast cell subtypes were analyzed by two-dimensional gel electrophoresis using either nonequilibrium pH gradient electrophoresis (NEPHGE) or isoelectric focusing (IEF) in the first dimension and SDS-PAGE (10%) in the second dimension followed by silver staining. PMC had seven dominant basic proteins (PB2-8; pI 9-9.5) with estimated molecular masses of 26 to 37 kDa, as well as 80 to 90 neutral or acidic proteins, most of which had pI 6 to 7.5 and estimated molecular masses of 20 to 100 kDa. All the basic proteins were granule-associated. Three basic proteins, PB6 (29 kDa), PB7 (28 kDa) and PB8 (RMCP I, 26 kDa), bound [3H]diisopropyl fluorophosphate (DFP), suggesting that they are serine proteases. However, only PB8 was reactive with antibodies to RMCP I. Another basic component (less than 14 kDa), perhaps a degradation product of PB6, PB7 or PB8, also bound [3H]DFP. By comparison, IMMC possessed nine basic proteins (IB1-9) and, in general, they were more acidic (pI about 8.5-9) than those of PMC. Four major basic proteins (IB6-9) were all 24 kDa but were slightly different in isoelectric points. These and another 46-kDa basic component (IB2) were reactive with antibodies to RMCP II and bound [3H]DFP. There were no other DFP-binding proteins in IMMC. In spite of remarkable differences between basic granule-associated proteins in PMC and basic proteins in IMMC, spots in the neutral-acidic range were for the most part similar in the two mast cell subsets, although quantitative differences were evident for some spots. Thus, rat mast cell populations from the peritoneal cavity and intestinal mucosa exhibit marked heterogeneity in their protein constituents with basic pI, including in their granule-associated proteins with serine protease activity.
Rabbit peritoneum was studied by SEM to obtain information and statistically meaningful morphometric data of different sites of visceral and parietal peritoneum and to verify the existence of “stomata.”
Samples were fixed by intraperitoneal infusion of glutaraldehyde, and were photographed by SEM under standard conditions. Morphometric data were obtained by Kontron MOP Videoplan. Variable cell surface patterns were present even within limited areas; however, “stomata” were not observed. The heterogeneity of data obtained can be related to the dynamism of mesothelial cell activity and to the different motilities of the underlying organs.
The topography and ultrastructure of the omentum in normal and stimulated mice were investigated with combined transmission (TEM) and scanning electron microscopy (SEM). The present study demonstrated that lymphocytes and monocytes were the principle cell types in the non-stimulated milky spot. Following stimulation with bacterial toxin and adjuvant there was an increased microvascular permeability to fluid, neutrophils, monocytes and fibrin deposits within the connective tissue matrix of milky spots, and a subsequent increased cellular migration across the mesothelial lining into the peritoneal cavity. Cellular migration from the milky spot to the peritoneal cavity is facilitated by the absence of a basal lamina from the submesothelial connective tissue layer, therefore, cells can migrate from the interstitial spaces of the milky spot to intercellular gaps between mesothelial cells without having to penetrate a fibrous barrier.
Previous studies showed the existence of submesothelial fenestrated capillaries in the human parietal and rabbit diaphragmatic peritoneum, as well as in the mouse mesentery. The present study demonstrates the presence of electronegative fixed charges at the luminal aspect of endothelial cells, as well as long the subendothelial basement membrane of the fenestrated capillaries of the mouse mesentery. This situation will eventually preclude the transfenestral passage of anionic plasma proteins. On the other hand, fenestrated capillaries are much more permeable to water and small-molecular-size solutes than those of the continuous type. Therefore, the high hydraulic conductivity of fenestrae may well imply that a substantial part of water and small solutes leave the blood compartment through the fenestral channels.
Fresh specimens of human peritoneum collected from heart-beating cadaver organ donors have been examined by transmission electron microscopy. Samples were taken from the anterior abdominal wall and from the surfaces of the liver, stomach and diaphragm. The mesothelium consisted of a single layer of flattened cells generally 2.5 microns to 3 microns thick. These were joined by tight junctions and desmosomes to form a continuous sheet. The cells rested on a prominent basement membrane deep to which was a layer of fibrous connective tissue. This layer was more compact under the mesothelium from the abdominal wall and liver than elsewhere. Long microvilli projected from apical surface of the cells. In many cases these covered the entire surface but sometimes they were more profuse at the edges of the cells near the intercellular junctions. The cells possessed a well-developed cytoskeleton of intermediate filaments which coursed through the cytoplasm in thick bundles. The cells also had a well-developed rough endoplasmic reticulum and Golgi apparatus. Numerous smooth-surfaced and coated vesicles could be seen adjacent to the plasmalemma at all surfaces, providing evidence of considerable pinocytotic activity. There was little regional variation in the structure of the mesothelium. We found no evidence of pores passing through the layer although, on the liver, cisternae were present between the cells and these were often occupied by lymphocytes.
Normal human peritoneal cells (PC) collected from patients with calculous cholecystitis without clinically detectable inflammatory changes were characterized morphologically, histochemically and phenotypically by means of monoclonal antibodies. The PC consisted of 45% of monocytes/macrophages (M718 + cells). Thirty-five per cent of PC were esterase-positive and 23% acid phosphatase positive. Forty-five per cent of PC adhered to glass surface. In the lymphocyte population, 2% of CD22 B lymphocytes (M738 +) and 42% CD2 T lymphocytes (M720+) were found. CD4/CD8 ratio was 0.4. There were 8% of Leu7 + cells. The PC did not reveal interleukin 2 (OKT26a +) and transferrin receptors (OKT9 +) on their surface. No blast cells were detected in the PC suspension. Approximately 49% of the PC expressed Ia antigens (OKIa1 +). Two per cent of S100 positive dendritic cells (Z311 +) were found. Peritoneal fluid contained 9% of granulocytes, mostly neutrophils. Two per cent of PC were free mesothelial cells (M717 +). We conclude that human peritoneal cavity contains a cell population significantly differing from that which is present in peripheral blood, which strongly suggests a non-random cell accumulation in the peritoneum. Lack of any activated cells indicates that under normal conditions the peritoneum lavage fluid contains a steady-state population. We conclude that the normal peritoneal fluid cells represent a heterogeneous population capable of reacting to various antigens entering the cavity from the gut.
A unifying pathophysiological hypothesis states that the plasminogen activating activity (PAA) of the peritoneal mesothelium determines whether the fibrin which forms after peritoneal injury is either lysed or organized into permanent fibrous adhesions. The PAA of human peritoneal biopsies was measured using a fibrin plate lysis technique to assess the changes that occur in inflammation and ischaemia, conditions which both produce fibrous adhesions. Activity was found in all biopsies from normal parietal and visceral (appendix, bowel and omentum) peritoneum with no significant site-to-site variation. Inflamed peritoneum (parietal, appendicular and mesenteric) had significantly less PAA compared with normal peritoneum; visceral ischaemia also resulted in a significant decrease of PAA. These reductions in human peritoneal PAA observed in inflammation and ischaemia support the view that mesothelial PAA plays a key part in the prevention of events leading to the production of fibrous adhesions.