Soyoon Yoon Choi

Background and aims Favourable clinical data were published on the efficacy of CT-P13, the first biosimilar of infliximab (IFX), in pediatric inflammatory bowel disease (IBD); however, few studies have compared the effect on endoscopic healing (EH) and drug retention rate between the IFX originator and CT-P13. Therefore, we aimed to compare EH and...

Background/aims: : The recent update on Selecting Therapeutic Targets in Inflammatory Bowel Disease initiative has added a decrease in fecal calprotectin (FC) to an acceptable range as an intermediate target for Crohn's disease (CD). We aimed to investigate whether postinduction FC could predict future persistent remission (PR) and endoscopic heal...

Background/aims: The recent update on the Selecting Therapeutic Targets in Inflammatory Bowel Disease initiative has added normal growth in children as an intermediate target in Crohn's disease and ulcerative colitis. We aimed to investigate factors associated with reaching mid-parental height (MPH) in patients diagnosed with inflammatory bowel di...

Introduction It is well known that infliximab (IFX) trough levels (TLs) are associated with endoscopic healing (EH) in Crohn’s disease (CD). We investigated whether IFX TLs are associated with transmural healing (TH) in pediatric patients with CD following 1-year treatment. Methods Pediatric patients with CD treated with IFX were included in this...

Background and objective: Automated detection of arrhythmias from electrocardiograms (ECGs) can be of considerable assistance to medical professionals in providing efficient treatment for patients with cardiovascular diseases. In recent times, convolutional neural network (CNN)-based arrhythmia classification models have been introduced, but their...

Purpose: Gastrointestinal (GI) endoscopy is an important tool for diagnosing and treating GI diseases in children. This study aimed to analyze the current GI endoscopy practice patterns among South Korean pediatric endoscopists. Methods: Twelve members of the Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition developed a ques...

Purpose: We aimed to investigate factors that correlate with fecal calprotectin (FC) levels in children and adolescents with colorectal polyps. Methods: Pediatric patients aged <19 years who underwent colonoscopic polypectomy for a juvenile polyps (JPs) and FC tests were simultaneously conducted in a multicenter, retrospective study. Baseline de...

Background and Objectives: The coronavirus disease 2019 (COVID-19) pandemic has affected medical practice in diverse ways. We aimed to investigate the change in trends of lower gastrointestinal (LGI) endoscopy conducted in children and adolescents after the COVID-19 outbreak in Korea. Material and Methods: This was a multicenter, retrospective stud...

Background: Studies on how the coronavirus pandemic has affected pediatric inflammatory bowel disease (PIBD) are lacking. We aimed to investigate the trends in epidemiology, characteristics, initial management, and short-term outcomes of PIBD in South Korea over the recent three years including the era of coronavirus disease 2019 (COVID-19). Meth...

Purpose: Eating disorders often result in somatic complications, including cardiac abnormalities. Cardiac abnormalities may involve any part of the heart, including the cardiac conduction system, and can lead to sudden cardiac death. The current study aimed to evaluate the incidence of cardiac complications in pediatric patients with eating disord...

Background/aims: A full colonoscopy is currently required in children and adolescents with colorectal polyps, because of their potential of neoplastic transformation and complications such as intussusception. We aimed to analyze the associations of polyp characteristics in children and adolescents with colorectal polyps. Based on these findings, w...

The vaccination of immunocompromised children against coronavirus disease 2019 is an important public health issue. We evaluated the serological response, safety, and effectiveness of the BNT162b2 vaccine in children with and without inflammatory bowel disease (IBD). A prospective, multicenter, case–control study was conducted in a pediatric popula...

Background/aims: The effects of probiotics in children vary based on diseases and probiotic strains. We aim to investigate the effectiveness of Saccharomyces boulardii and lactulose for treating childhood functional constipation. Methods: This open-label randomized controlled trial was conducted at 10 university hospitals in Korea. Children who...

Background The optimal treatment goal in Crohn's disease (CD) is endoscopic healing (EH). However, transmural healing (TH) facilitated by the development and increasing performance of magnetic resonance enterography (MRE) is emerging as a potential treatment goal. Aims To assess TH rates after 1 year of treatment by MRE and its relationship with E...

We investigated whether the severity of anxiety among children undergoing endoscopy could affect sedation. We prospectively recruited patients under 18 years of age who were scheduled to undergo esophagogastroduodenoscopy (EGD). Baseline anxiety was evaluated using the Spence Children’s Anxiety Scale (SCAS). Our analysis considered the type and dos...

The introduction of biological agents with strong anti-inflammatory action, such as antitumor necrosis factor (TNF) agents, has changed inflammatory bowel disease (IBD) treatment strategy and goals, and has contributed significantly to improve the long-term prognosis of patients. Moreover, several biological agents are being used or researched in p...

Background: Colorectal polyps are the most common cause of isolated hematochezia in children, which requires a colonoscopy for diagnosis. We aimed to investigate the potential utility of fecal calprotectin (FC) in assessing colorectal polyps detected by colonoscopy among children presenting with isolated hematochezia. Methods: Pediatric patients...

Background NUDT15 polymorphisms are associated with leukopenia during treatment with thiopurines. However, data regarding its effect on treatment outcomes are scarce. Aims To investigate the outcomes between NUDT15 normal and intermediate metabolisers in paediatric patients with Crohn's disease (CD) treated with a combination therapy of infliximab...

Background: Abnormal liver function tests (LFTs) are commonly seen in pediatric patients with acute infectious diseases. Few studies and no definite clinical guidelines for these conditions are available. The present study aimed to elucidate the causes and factors associated with prolongation of liver enzyme elevation. We also investigated actual...

Background: The occurrences of infection-related systematic diseases, such as Henoch-Schönlein Purpura (HSP), intussusception, and mucocutaneous lymph node syndrome (MCLS) may have decreased, similarly to the decreased occurrence of infectious diseases following the Coronavirus disease 2019 (COVID-19) pandemic. We aimed to investigate whether ther...

Pediatric-onset inflammatory bowel disease differs from adults in its epidemiological and clinical characteristics and courses. Since it is diagnosed at a young age, the duration of the disease is relatively longer than in adults. Therefore, it is necessary to select drugs in consideration of long-term risks and benefits, and efforts such as therap...

Background: It is uncertain whether non-alcoholic fatty liver disease (NAFLD) is associated with subclinical hypothyroidism (SH) in pediatric patients. The purpose of this study was to investigated the prevalence and related factors of SH in pediatric patients with NAFLD. We also evaluate the association between liver fibrosis and SH. Methods: W...

Background: Sedative upper endoscopy is similar in pediatrics and adults, but it is characteristically more likely to lead to respiratory failure. Although recommended guidelines for pediatric procedural sedation are available within South Korea and internationally, Korean pediatric endoscopists use different drugs, either alone or in combination,...

Background Abnormal liver function tests (LFTs) are commonly seen in pediatric patients with acute infectious diseases; few studies and no definite clinical guidelines for these conditions are available. This study aimed to elucidate the causes and factors associated with prolongation of liver enzyme elevation. We also investigated actual real-worl...

Background/objectives: To evaluate the nutritional status and prevalence of malnutrition in hospitalized children at admission and during hospitalization in South Korea. Subjects/methods: This first cross-sectional nationwide "Pediatric Nutrition Day (pNday)" survey was conducted among 872 hospitalized children (504 boys, 368 girls; 686 medical,...

Purpose: In patients with acute enterocolitis, radiologic findings are sometimes accompanied by secondary inflammation of the appendix. The purpose of this study was to evaluate the clinical features of acute enterocolitis with secondary inflammation of the appendix. Methods: Medical records from patients who underwent abdominal ultrasonography...

In Korea, several national cross-sectional surveys monitor the diet, nutritional status, and health status of children. This continual dedicated national surveillance system contributes to the identification of nutritional and health issues, establishment of public health policies, and development of nutrition recommendations. This paper provides r...

Background In patients with acute gastroenteritis, radiologic findings are sometimes accompanied by secondary inflammation of the appendix. The purpose of this study was to evaluate the clinical features of acute gastroenteritis with secondary inflammation of the appendix. Methods Medical records from patients who underwent abdominal ultrasonograp...

Background: Limited data exist regarding mucosal healing (MH) and therapeutic drug monitoring (TDM) in pediatric Crohn's disease (CD) patients treated with adalimumab (ADL). We aimed to investigate the associations between ADL trough levels (TLs) and MH, and between ADL TLs and histologic remission (HR) at 16 weeks from ADL treatment in pediatric...

Hydrogen peroxide is a strong oxidizing agent widely available as disinfectants. It can be harmful if it enters into the bowels. Within moments after gastrointestinal exposure, the colon becomes distended with reduced blood flow. The reaction with catalase can cause acute colitis due to the release of oxygen. We present a case of a child with hydro...

Purpose: We aimed to investigate the disease phenotype of Korean pediatric Crohn's disease (CD) patients at diagnosis according to the Paris classification by comparison with patients from the European multicenter 5-years recruitment of children with newly developed IBD (EUROKIDS registry). Methods: Korean children and adolescents who had been n...

Eosinophilic gastroenteritis is a member of eosinophilic gastrointestinal (GI) diseases and is characterized by the accumulation of eosinophils within the GI tract. Common symptoms of eosinophilic gastroenteritis are vomiting, abdominal pain, dysphagia, and weight loss, but rare fever in neonate. This report describes a 10-day-old boy who developed...

Purpose We investigated the effect of delayed elevation of thyrotropin (TSH) (deTSH) on gastrointestinal motility in very low birth weight infants (VLBWI). Methods This study retrospectively investigated 228 premature VLBWI aged ≥4 weeks with normal neonatal TSH screening test results and free serum thyroxine levels. Infants with serum TSH levels r...

Background/aims: Infliximab (IFX) often loses its therapeutic effect in initial responders with inflammatory bowel disease (IBD) over time. Low serum IFX trough levels (TLs) are linked to poor clinical response and outcomes. Maintenance of optimal therapeutic IFX concentrations is important for sustaining response and achieving good clinical outco...

Background and aims: Mucosal healing is an important treatment goal in Crohn's disease. We investigated the association between serum infliximab trough levels and mucosal healing, and the infliximab cut-off levels required for mucosal healing in paediatric patients. Methods: In this multicentre, retrospective, cross-sectional study, medical reco...

Glycogen storage disease (GSD) IV is a rare autosomal recessive inherited disorder caused by mutations in the gene coding for glycogen branching enzyme leading to progressive liver disease. GSD IV is associated with mutations in GBE1, which encodes the glycogen branching enzyme. We report a case of GSD IV with rare homozygous mutations in the GBE1...

Background and aims: We aimed to investigate the outcome in paediatric-onset Crohn's disease patients who had discontinued infliximab after maintaining clinical remission with combined immunosuppression, and to determine factors associated with clinical relapse. Methods: We conducted a retrospective observational study of 63 paediatric-onset Cro...

Background/aims: The clinical use of measuring infliximab (IFX) trough levels (TLs) and antibodies against IFX (ATIs) in patients with pediatric inflammatory bowel disease (IBD) remains unclear. We propose measuring these variables to create individual IFX treatment strategies for patients with pediatric IBD. Methods: This retrospective study wa...

Purpose: We aimed to investigate the efficacy and safety of adalimumab in pediatric-onset Crohn's disease patients who had failed treatment with infliximab. Methods: In this retrospective study, patients included were those who had been diagnosed with Crohn's disease before 18 years old, and had received treatment with adalimumab after inflixima...

Background Molecular diagnosis of glycogen storage diseases (GSDs) is important to enable accurate diagnoses and make appropriate therapeutic plans. The aim of this study was to evaluate the PHKA2 mutation spectrum in Korean patients with GSD type IX. Methods Thirteen Korean patients were tested for PHKA2 mutations using direct sequencing and a mu...

Background and aims: We aimed to compare the efficacy of combined immunosuppression in terms of mucosal healing in paediatric patients with moderate-to-severe luminal Crohn's disease receiving infliximab according to either an 'escalated combined immunosuppression' or an 'early combined immunosuppression' strategy. Methods: In this prospective o...

Objectives: We aimed to quantitatively investigate the therapeutic response to combined immunosuppression treatment by magnetic resonance enterography (MRE) in active luminal Crohn's disease in the pediatric population. Methods: Pediatric patients with moderate-to-severe luminal Crohn's disease who received scheduled infliximab and azathioprine...

Purpose: Infants with Alagille syndrome (AGS) are occasionally misdiagnosed as biliary atresia and subsequently undergo Kasai operation. The purpose of this study was to investigate the outcome of patients with AGS who had previously received Kasai operation during infancy. Methods: This retrospective study was conducted at the Department of Ped...

Mycoplasma pneumoniae is responsible for approximately 20% to 30% of community-acquired pneumonia, and is well known for its diverse extrapulmonary manifestations. However, acute necrotizing pancreatits is an extremely rare extrapulmonary manifestation of M. pneumoniae infection. A 6-year-old girl was admitted due to abdominal pain, vomiting, fever...

Thiopurine-related toxicity results in discontinuation of therapy in up to 30% of patients with inflammatory bowel disease. Although thiopurine S-methyltransferase (TPMT) is implicated in toxicity, not all toxicity can be attributed to TPMT polymorphisms. We investigated the effects of polymorphisms of genes involved in thiopurine and folate metabo...

Background: Azathioprine (AZA) is commonly used to treat IBD either alone or in combination with mesalazine. However, there are relatively few studies concerning the relationship between AZA dose, thiopurine metabolite levels, and therapeutic response in pediatric patients treated with both AZA and mesalazine. Methods: We retrospectively investi...

There are no studies of hepatic glycogen storage diseases (GSDs) other than type I and III in Korea. We aimed on investigating the characteristics of hepatic GSDs in Korea diagnosed and followed at a single center. We retrospectively analyzed patients who were diagnosed as GSD and followed at Samsung Medical Center from January, 1997 to December, 2...