Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

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 midparental height (MPH) in patients diagnosed with inflammatory bowel disease in childhood and the adolescent period. Methods: This multicenter retrospective observational study included pediatric patients with inflammatory bowel disease that had reached adult height. Factors associated with reaching MPH were investigated by logistic regression analyses. Results: A total of 166 patients were included in this study (128 Crohn’s disease and 38 ulcerative colitis). Among them, 54.2% (90/166) had reached their MPH. Multivariable logistic regression analysis revealed that height Z-score at diagnosis and MPH Z-score were independently associated with reaching MPH (odds ratio [OR], 8.45; 95% confidence interval [CI], 4.44 to 17.90;p<0.001 and OR, 0.11; 95% CI, 0.04 to 0.24; p<0.001, respectively). According to the receiver operating characteristic curve analysis, the optimal cutoff level of "height Z-score at diagnosis minus MPH Z-score" that was associated with reaching MPH was –0.01 with an area under the curve of 0.889 (95% CI [0.835 to 0.944], sensitivity 88.9%, specificity 84.2%, positive predictive value 87.0%, negative predictive value 86.5%, p<0.001). Conclusions Height Z-score at diagnosis and MPH Z-score were the only factors associated with reaching MPH. Efforts should be made to restore growth in pediatric patients who present with a negative “height Z-score at diagnosis minus MPH Z-score.”

Background: By analyzing small bowel capsule endoscopy (SBCE) performed in two large hospitals in Kazakhstan, we aimed to explore the characteristics of patients representative of Central Asia and the technical characteristics of SBCE. Methods: SBCE cases were retrospectively analyzed. A descriptive analysis was conducted on the patients’ demographic data, diagnosis, and clinical symptoms. The results of SBCE, such as the lesions found, transit time and retention rate in the stomach and small bowel, and bowel visualization quality, were analyzed. Complications related to SBCE were investigated. Results: SBCE was performed in 123 patients. Abdominal pain (81.3%) and chronic diarrhea (66.7%) were the most common symptoms, followed by weight loss (25.2%) and gastrointestinal bleeding (15.4%). The most common disease was Crohn’s disease (52.0%). Definite lesions, such as ulcers, polyps, and bleeding, were identified in 55.3% of patients. SBCE was successfully completed in all cases except for 11 (9.1%). The average small bowel transit time was 4 hours and 28 minutes. Excellent visualization (>75% of mucosa) was reported in 82.5% of patients. No patients experienced complications. Conclusions SBCE performed in Kazakhstan showed a high diagnostic yield with high-quality patient selection and no complications.

Purpose: Acetaminophen overdose accounts for the largest proportion of pediatric poisoning reported in South Korea. We investigated the characteristics and prognosis of pediatric acetaminophen overdose. Methods: We retrospectively reviewed medical records of patients younger than 19 years with acetaminophen overdose who visited the emergency department (ED) of Pusan National University Children’s Hospital from January 2009 through December 2022. We investigated age, sex, dose, clinical findings, and treatment, and compared the differences in the variables according to the intentionality of ingestion and the presence of hepatotoxicity. Results: Among the 132,691 pediatric patients who visited the ED during the period, 555 did for drug intoxication, of whom 51 with acetaminophen overdose were included in this study. The overdose was intentional in 43 patients (the intentional group; median age, 15.4 years [interquartile range, 13.9-16.8]) and accidental in 8 patients (the accidental group; 7.7 years [2.3-15.4]). The mean ingested dose was higher in the intentional group than in the accidental group (170.3 ± 129.0 vs. 105.3 ± 37.5 mg/kg; P = 0.016). Hospitalization tended to be implemented more frequently in the intentional group (53.5% vs. 12.5%; P = 0.081). All patients with hepatotoxicity (n = 10) belonged to the same group, and showed a higher or longer median age (15.9 [14.6-17.1] vs. 13.8 years [13.7-16.4]; P = 0.030), mean ingested dose (13,230.0 ± 10,544.8 vs. 7,654.0 ± 6,752.3 mg; P = 0.043), mean time from ingestion to arrival at the ED (22.6 ± 23.4 vs. 5.5 ± 6.4 hours; P = 0.048), and frequency of hospitalization (80.0% vs. 39.0%; P = 0.048). Conclusion It is necessary to track the occurrence of hepatotoxicity in patients who intentionally ingest acetaminophen.

Purpose: To date, there is no region-specific guideline for pediatric endoscopy training. This study aimed to illustrate the current status of pediatric endoscopy training in Asia-Pacific region and identify opportunities for improvement. Methods: A cross-sectional survey, using a standardized electronic questionnaire, was conducted among medical schools in the Asia-Pacific region in January 2024. Results: A total of 57 medical centers in 12 countries offering formal Pediatric Gastroenterology training programs participated in this regional survey. More than 75% of the centers had an average case load of <10 cases per week for both diagnostic and therapeutic endoscopies. Only 36% of the study programs employed competency-based outcomes for program development, whereas nearly half (48%) used volume-based curricula.Foreign body retrieval, polypectomy, percutaneous endoscopic gastrostomy, and esophageal variceal hemostasis, that is, sclerotherapy or band ligation (endoscopic variceal sclerotherapy and endoscopic variceal ligation), comprised the top four priorities that the trainees should acquire in the autonomous stage (unconscious) of competence. Regarding the learning environment, only 31.5% provided formal hands-on workshops/simulation training. The direct observation of procedural skills was the most commonly used assessment method. The application of a quality assurance (QA) system in both educational and patient care (Pediatric Endoscopy Quality Improvement Network) aspects was present in only 28% and 17% of the centers, respectively. Conclusion Compared with Western academic societies, the limited availability of cases remains a major concern. To close this gap, simulation and adult endoscopy training are essential. The implementation of reliable and valid assessment tools and QA systems can lead to significant development in future programs.

Objective: : Endothelial colony-forming cells (ECFCs) have been reported to play an important role in the pathogenesis of moyamoya disease (MMD). We have previously observed stagnant growth in MMD ECFCs with functional impairment of tubule formation. We aimed to verify the key regulators and related signaling pathways involved in the functional defects of MMD ECFCs. Methods: : ECFCs were cultured from peripheral blood mononuclear cells of healthy volunteers (normal) and MMD patients. Low-density lipoproteins uptake, flow cytometry, high content screening, senescence-associated β-galactosidase, immunofluorescence, cell cycle, tubule formation, microarray, real-time quantitative polymerase chain reaction, small interfering RNA transfection, and western blot analyses were performed. Results: : The acquisition of cells that can be cultured for a long time with the characteristics of late ECFCs was significantly lower in the MMD patients than the normal. Importantly, the MMD ECFCs showed decreased cellular proliferation with G1 cell cycle arrest and cellular senescence compared to the normal ECFCs. A pathway enrichment analysis demonstrated that the cell cycle pathway was the major enriched pathway, which is consistent with the results of the functional analysis of ECFCs. Among the genes associated with the cell cycle, cyclin-dependent kinase inhibitor 2A (CDKN2A) showed the highest expression in MMD ECFCs. Knockdown of CDKN2A in MMD ECFCs enhanced proliferation by reducing G1 cell cycle arrest and inhibiting senescence through the regulation of CDK4 and phospho retinoblastoma protein. Conclusion : Our study suggests that CDKN2A plays an important role in the growth retardation of MMD ECFCs by inducing cell cycle arrest and senescence.

Background: Swallowing of foreign bodies (FBs) is the most common indication of therapeutic endoscopy in children. Endoscopic removal may be necessary depending on the type of FB, age of the child, and location of the FB. We attempted to analyze the characteristics of each device used for the endoscopic removal of FBs in children. Methods: Medical records of the patient’s age, sex, weight, type, location, size, shape, type of device used for endoscopic removal, and endoscopic time were retrospectively collected. Results: A total of 424 FB removal procedures were analyzed. The average age of the patients at the time of FB removal was 4.1 ± 3.7 years. Coins were the most common FBs (192, 45.3%). The most common locations of the FBs were the esophagus (45.7%) and the stomach (48.3%), respectively. For a total of 371 cases, forceps were used in 96 cases (25.9%) for esophageal FBs and in 25 cases for gastric FBs (6.7%), while nets were used in 250 cases (67.4%) for gastric FBs retrieval; the average durations of the procedures were 7.2 ± 7.4 minutes, 8.5 ± 7.2 minutes, and 5.7 ± 7.3 minutes, respectively (P = 0.003). The procedure time was significantly shorter, in the group of patients with low body weights, when nets were used than when forceps were used to remove gastric FBs (P = 0.001). Conclusion The endoscopic procedure duration, in low-weight children, was shorter when retrieval nets were used than that with forceps.