Pediatric Lower Gastrointestinal Bleeding: Endoscopic and Histopathologic Spectrum in a 16-Year Tertiary-Center...

Objectives: Pediatric lower gastrointestinal bleeding encompasses a broad and age-dependent spectrum of conditions, ranging from benign anorectal disorders to inflammatory bowel disease, colorectal polyps, and less common structural or vascular lesions. Despite advances in diagnostic evaluation, contemporary pediatric data on the distribution of underlying diagnoses, particularly according to age and sex, remain limited. This study aimed to evaluate the endoscopic and histopathologic spectrum of pediatric lower gastrointestinal bleeding and to examine age- and sex-related diagnostic patterns. Methods: This retrospective single-center study included children aged 0-18 years who presented with overt lower gastrointestinal bleeding and underwent colonoscopic evaluation at a tertiary pediatric gastroenterology center between May 2010 and May 2026. Demographic data, colonoscopic and histopathologic findings, final diagnoses, inflammatory bowel disease subtypes, and polyp histopathology were reviewed. Patients were categorized into four age groups: 0-3, 4-6, 7-12, and 13-18 years. Results: A total of 268 children were included. The mean age was 11.4 ± 4.9 years, and 130 patients were female (48.5%). The most common diagnosis was inflammatory bowel disease, identified in 79 patients (29.5%), including 62 with ulcerative colitis and 17 with Crohn's disease. Normal colonoscopic and histopathologic findings were observed in 65 patients (24.3%), anal fissure in 63 (23.5%), and polypoid lesions in 30 (11.2%). Juvenile polyp was the most common polyp subtype. Diagnostic distribution differed significantly across age groups (p < 0.001). Inflammatory bowel disease was more frequent among adolescents, whereas polypoid lesions were most common in children aged 4-6 years. Exploratory sex-based analyses suggested a female predominance in ulcerative colitis and a male predominance in Crohn's disease and polypoid lesions. Conclusions: In children undergoing colonoscopic evaluation for lower gastrointestinal bleeding, inflammatory bowel disease, normal findings, anal fissure, and polypoid lesions were the leading diagnostic categories. Age- and sex-related patterns may help guide clinical evaluation and interpretation of colonoscopic and histopathologic findings.