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Lung transplant recipients (LTRs) are vulnerable to hyperammonemia syndrome (HS) in the early postoperative period, a condition typically unresponsive to nonantibiotic interventions. HS in LTRs is strongly correlated with Ureaplasma infection of the respiratory tract, although it is not well understood what makes LTRs preferentially susceptible to...
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Context 1
... flow system. 10-mL cultures of 10 5 CCU/mL for all Ureaplasma isolates were encased in dialysis tubing (Specta/Por Float-A-Lyzer G2 1,000-kDa dialysis device; G235073) and submerged in 250 mL of 100 mM MES-buffered U9, allowing measurement of NH 3 levels over time (Fig. 5). The entire device was incubated at 37°C, with fresh broth added and spent media removed via flow at 2 mL/hour. Urea concentrations in the growth media were varied to mimic normal and high BUN levels (10 and 50 mg/dL, respectively) in the flow chamber and inflow and were maintained at a standard deviation of 3 for the 50 mg/mL ...
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Ureaplasma urealyticum and Ureaplasma parvum are important causes of septic arthritis in patients with hypogammaglobulinemia. The diagnosis can be challenging, leading to prolonged illness and increased morbidity, and mortality. This is driven by the complex growth media requirements of Ureaplasma species and the difficulty in identifying the organ...
Citations
... Uremia (UR) is a terminal renal failure manifestation, which refers to a clinical syndrome consisting of a series of symptoms and metabolic disorders resulting in a progressive and irreversible decline in kidney function until functional loss [1]. UR patients may present systemic system damage, including gastrointestinal symptoms (e.g., nausea and vomiting) in most patients, severe anemia, fatigue and palpitation in some cases, and heart failure, consciousness disorders, and even death in severely ill patients [2]. In recent years, the prevalence of UR has shown an obvious upward trend, posing a grave potential threat to patients' lives and health [3]. ...
... In addition to raising the pH of the local environment, ammonia also irritates mucous membranes to facilitate increased pathogen adherence and colonization. However, the hyperammonemia syndrome seems to have several contributors other than infection [17][18][19], and mainly occurs in patients with impaired renal function, who have elevated blood levels of urea, the substrate of urease for ammonia production [17,19,20]. Our patient had a high-normal ammonia level the only time it was checked, during her second hospitalization. ...
Genital mycoplasmas are sexually transmitted Mollicutes with a high prevalence of urogenital tract colonization among females of reproductive age. Current guidelines recommend against routine screening for these organisms, since their role in the pathogenesis of pelvic inflammatory disease and tubo-ovarian abscesses (TOAs) remains unclear. However, genital mycoplasmas harbor pathogenic potential in immunocompromised hosts, especially patients with hypogammaglobulinemia. It is important to identify such infections early, given their potential for invasive spread and the availability of easily accessible treatments. We present a young adult female with multiple sclerosis and iatrogenic hypogammaglobulinemia, with refractory, bilateral pelvic inflammatory disease and TOAs due to Ureaplasma urealyticum, identified as a single pathogen via three distinct molecular tests. To our knowledge, this is the second case of TOAs caused by U. urealyticum in the literature, and the first diagnosed by pathogen cell-free DNA metagenomic next-generation sequencing in plasma.
... As recently hypothesized by Fleming et al, elevated blood urea could potentially contribute to the overproduction of ammonium by Ureaplasma species. Lung transplant recipients commonly experience postoperative uremia because of acute renal failure [15]. ...
Hyperammonemia after lung transplantation is a rare but potentially fatal condition. A 59-year-old male patient affected by pulmonary fibrosis underwent an uncomplicated bilateral lung transplant. Fourteen days after the procedure, the patient developed severe encephalopathy caused by elevated serum ammonia levels. Ureaplasma parvum and Mycoplasma hominis were found on bronchial aspirate and urinary samples as well as on pharyngeal and rectal swabs. Despite the initiation of multimodal therapy, brain damage due to hyperosmolarity was so extensive to evolve into brain death. The autopsy revealed glutamine synthetase hypo-expression in the hepatic tissue. The pathophysiology of hyperammonemia syndrome in lung transplant recipients remains unclear. Previous studies have described the presence of disorders of glutamine synthetase, while others considered the infection with urea-splitting microorganisms as a cause of hyperammonemia syndrome. Our report describes the case of a patient who developed hyperammonemia after a lung transplant in which both the aforementioned etiologies were documented. A high level of clinical suspicion for hyperammonemia syndrome should be maintained in lung transplant recipients. Timely recognition and treatment are critical to prevent the potentially dreadful evolution of this severe complication.
... Several recent studies have found the rapid progression of hyperammonemia and high mortality after lung transplantation. UU infection could cause hyperammonemia in patients after lung transplantation [3,7,8]. This study reports two cases of fatal multiple organ dysfunction following lung transplantation caused by genital commensal UU in combination with HSV-2 infection. ...
Background
Infection following lung transplantation has been the focus of clinical concerns. The colonization rate of commensal bacteria of the urogenital tract, including Mycoplasma hominis, Ureaplasma urealyticum (UU), and herpes simplex virus type-2 (HSV-2), is high, which may cause secondary infection after transplantation.
Case presentation
Twenty-three-year-old and 67-year-old women underwent lung transplantation for different causes. Shortly after the operation, they developed perineal skin ulcers, hypoxia, and intractable epilepsy. Subsequent computed tomography (CT) of the chest showed lung consolidation, and cranial CT showed shallowing sulci and gyri. UU and HSV-2 were detected in bronchoalveolar lavage fluid by next-generation sequencing, and HSV-2 was shown in the cerebrospinal fluid of both patients. Despite active treatment, both suffered irreversible brain function damage within 72 h of the seizure.
Conclusions
Clinicians should know that commensal bacteria of urogenital tract infections can lead to fatal multiple organ dysfunction after lung transplantation.
... LTRs who become colonized with the human-associated Ureaplasma species, U. urealyticum and U. parvum, are particularly vulnerable to bacterial overproduction of NH 3 to such a degree that it overwhelms host detoxification capacity, resulting in cerebral edema and often death (9)(10)(11)(12)(13). Although the mechanisms that make LTRs exceptionally vulnerable to this clinical manifestation are not completely understood, the heavily immunocompromised status of LTRs, coupled with infection site advantages, such as ischemic tissue resulting from incomplete lung revascularization, and increased urea availability due to uremia resulting from acute renal failure (14), are likely contributing factors. Although Ureaplasma-directed antibiotic therapy can be curative and preventative in these patients, greatly reducing mortality (15,16), antibiotic use can lead to selection of resistance, resulting in relapse and treatment failure (1). ...
... U. parvum IDRL-10774 aliquots were pelleted at 15,000 Â G for 20 min at 4°C and resuspended in saline or saline 1 0.1% agar. C3H male and female mice (18-22 g, Charles River Laboratories, Wilmington, MA) were pharmacologically immunosuppressed for 7 days with methylprednisone, tacrolimus, and mycophenolate mofetil, and administered 40 g/L urea ad libitum in drinking water for 10 days to induce mild uremia, as previously described (14). Following immunosuppression and uremic induction, mice were administered 6 mg/kg flurofamide via IP injection (based on Ligon and Kenney 1990) (20), 1 h prior to IT and IP Ureaplasma challenge. ...
... Sample input was 200 mL and elution output 100 mL. qPCR for Ureaplasma was performed as previously described on a LightCycler 480 II (Roche Applied Science) (14,23). ...
Ureaplasma -associated hyperammonemia syndrome occurs in 4% of lung transplant recipients and has historically been almost universally fatal. While Ureaplasma -targeted antibiotics have been shown to be protective, the possibility of underlying resistance and resistance selection render non-antibiotic interventions an interesting approach.
... Uremia is a series of poisoning symptoms when acute or chronic renal insufficiency develops to a serious stage, often accompanied by water, electrolyte disorder, endocrine dysfunction, and other symptoms, which poses a serious threat to the life safety of patients [14][15][16]. Hemodialysis is one of the important treatment methods for patients with uremia, which can effectively improve the survival rate of patients. It is affected by economic conditions and physical aspects. ...
Aim:
Patients in the hemodialysis stage are prone to psychological pressure of depression and anxiety and have resistance, which affects the clinical treatment effect. Effective psychological intervention plays a very important role in improving patients' psychological pressure and patients' compliance. The aim of this study is to explore the nursing effect of psychological intervention on uremic hemodialysis patients.
Methods:
There were 126 uremic hemodialysis patients admitted to the hospital from August 2020 to December 2021. The patients were randomly divided into the routine nursing care group (n = 63) and psychological intervention group (n = 63). The routine nursing care group received routine nursing care for uremia hemodialysis patients. The psychological intervention group implemented psychological intervention on uremia hemodialysis patients. The methods of psychological intervention mainly include establishing a good nurse-patient relationship, popularizing hemodialysis knowledge, timely psychological counseling for patients, and organizing patient communication meetings. The treatment compliance, Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) of the two groups were compared before and after nursing. SF-36 scale was used to evaluate the quality of life of patients. The incidence of complications and nursing satisfaction were compared between the two groups.
Results:
The treatment compliance rate and nursing satisfaction of hemodialysis uremic patients in the psychological intervention group were significantly higher than the routine nursing care group. The SAS and SDS of hemodialysis uremia patients in the psychological intervention group were significantly lower than the routine nursing care group after psychological intervention, and SF-36 scale was significantly higher than the routine nursing group. The main complications of uremic hemodialysis patients are hypotension, hyperkalemia, internal fistula occlusion, and infection. Compared with the routine nursing care group, the incidence of complications in the psychological intervention group was significantly reduced.
Conclusion:
The implementation of psychological nursing intervention for uremic hemodialysis patients have a very significant effect on reducing the incidence of complications and improving anxiety, depression, treatment compliance, and the quality of life and the nursing satisfaction.
Cryptococcus neoformans and Cryptococcus gattii are both known urease producers and have the potential to cause hyperammonemia. We hypothesized that the risk of hyperammonemia is increased by renal failure, burden of cryptococcal infection, and fungal strain characteristics. We performed a retrospective review of plasma ammonia levels in patients with cryptococcal infections. Risk factors for hyperammonemia were statistically compared between patients with and without hyperammonemia (>53 µmol/L). Cryptococcal cells from three patients included in the study were recovered from our biorepository. Strain characteristics including urease activity, ammonia production, growth curves, microscopy, melanin production, and M13 molecular typing were analyzed and compared with a wild-type (WT) C. neoformans strain. We included 29 patients, of whom 37.9% had hyperammonemia, 59% had disseminated cryptococcal infection (DCI), and 41% had isolated central nervous system infection. Thirty-eight percent of patients had renal failure and 28% had liver disease. Renal failure was associated with 4.4 times (95% confidence interval [CI] 1.5, 13.0) higher risk of hyperammonemia. This risk was higher in DCIs (RR 6.2, 95% CI 1.0, 40.2) versus isolated cryptococcal meningitis (RR 2.5, 95% CI, 0.40, 16.0). Liver disease and cryptococcal titers were not associated with hyperammonemia. C. neoformans from one patient with extreme hyperammonemia demonstrated a 4- to 5-fold increase in extracellular urease activity, slow growth, enlarged cell size phenotypes, and diminished virulence factors. Hyperammonemia was strongly associated with renal failure in individuals with DCI, surpassing associations with liver failure or cryptococcal titers. However, profound hyperammonemia in one patient was attributable to high levels of urease secretion unique to that cryptococcal strain. Prospective studies are crucial to exploring the significance of this association.
IMPORTANCE
Cryptococcus produces and secretes the urease enzyme to facilitate its colonization of the host. Urease breaks down urea into ammonia, overwhelming the liver’s detoxification process and leading to hyperammonemia in some hosts. This underrecognized complication exacerbates organ dysfunction alongside the infection. Our study investigated this intricate relationship, uncovering a strong association between the development of hyperammonemia and renal failure in patients with cryptococcal infections, particularly those with disseminated infections. We also explore mechanisms underlying increased urease activity, specifically in strains associated with extreme hyperammonemia. Our discoveries provide a foundation for advancing research into cryptococcal metabolism and identifying therapeutic targets to enhance patient outcomes.
Human Ureaplasma species are being increasingly recognized as opportunistic pathogens in human genitourinary tract infections, infertility, adverse pregnancy, neonatal morbidities, and other adult invasive infections. Although some general reviews have focused on the detection and clinical manifestations of Ureaplasma spp., the molecular epidemiology, antimicrobial resistance, and pathogenesis of Ureaplasma spp. have not been adequately explained. The purpose of this review is to offer valuable insights into the current understanding and future research perspectives of the molecular epidemiology, antimicrobial resistance, and pathogenesis of human Ureaplasma infections. This review summarizes the conventional culture and detection methods and the latest molecular identification technologies for Ureaplasma spp. We also reviewed the global prevalence and mechanisms of antibiotic resistance for Ureaplasma spp. Aside from regular antibiotics, novel antibiotics with outstanding in vitro antimicrobial activity against Ureaplasma spp. are described. Furthermore, we discussed the pathogenic mechanisms of Ureaplasma spp., including adhesion, proinflammatory effects, cytotoxicity, and immune escape effects, from the perspectives of pathology, related molecules, and genetics.
Bacterial commensals of the human genitourinary tract, Mycoplasma hominis and Ureaplasma species (parvum and urealyticum) can be sexually transmitted, with the potential to cause non-gonococcal urethritis, pelvic inflammatory disease, and infertility. M. hominis and Ureaplasma spp. may also cause severe invasive infections in immunocompromised patients. Current culture-based methods for Mycoplasma/Ureaplasma identification are costly and laborious, with a turnaround time between 1-2 weeks. We developed a high-throughput, real-time multiplex PCR assay for the rapid detection of M. hominis and Ureaplasma spp. in urine, genital swab, body fluid, and tissue. In total, 282 specimens were tested by PCR and compared with historical culture results; a molecular reference method was used to moderate discrepancies. Overall result agreement was 99% for M. hominis (97% positive percent agreement (PPA), 100% negative percent agreement (NPA)) and 96% for Ureaplasma spp. (96% PPA, 97% NPA). Specimen stability was validated for up to 7 days at room temperature. This multiplex molecular assay was designed for implementation in a high-complexity clinical microbiology lab. With this method, >90 samples can be tested in one run, with a turnaround time of 4-5 hours from specimen extraction to reporting of results. This PCR test is also more labor- and cost-effective than the conventional culture-based test, thus improving laboratory efficiency and alleviating strains due to labor shortages.
