Disease patterns among Saudi children undergoing colonoscopy for lower gastrointestinal bleeding: Single tertiary care center experience.

Background: : The yield of colonoscopy in cases presenting with lower gastrointestinal bleeding (LGIB) in previously published studies varies according to several factors, including endoscopic skills, histopathological experience, and pattern of colonic pathology in different countries. The local literature is limited to a single small 20-year-old study. Our objective was to provide updated data on the diagnostic yield of colonoscopy in Saudi children with LGIB in Saudi Arabia.

Methods: : This was a retrospective analysis of pediatric patients (0-14 years of age) who underwent colonoscopy for LGIB at the King Fahad Medical City (KFMC), from 2008 to 2018. LGIB was defined as fresh or dark blood per rectum.

Results: : During the study period, 175 children underwent colonoscopy for LGIB (99 males, mean age 7.05 ± 3.81 years), which constituted 53.5% of indications for colonoscopy procedures (n = 327) in our center. The terminal ileum was intubated in 81% of the procedures. Overall, inflammatory bowel disease (IBD) was the most commonly identified cause of LGIB (32% ) followed by colonic lymphonodular hyperplasia (CLNH) in 17% and juvenile polyp and rectal mucosal prolapse syndrome (RMPS), 11% each. On sub-analysis, cow's milk protein allergy (CMPA) and CLNH were the most common causes in infants and toddlers, 35% each; IBD (26.5%) and polyps (22.4%) in young children (2-6 years), and IBD (36%), CLNH (14.9%) and RMPS (14%) in older children (6-14 years). In comparing the IBD to the non-IBD group, IBD patients were older (mean 8.37 vs. 6.46 years, P = 0.002) and more likely to have diarrhea, weight loss, high erythrocyte sedimentation rate, anemia, and hypoalbuminemia (odds ratio 24, 11, 10.7, 6.5, and 4, respectively). Colonoscopy had a sensitivity of 97%, specificity of 100%, positive predictive value of 100%, negative predictive value of 81.4%, and accuracy of 97% in diagnosing LGIB.

Conclusion: : Colonoscopy is an effective diagnostic tool in children with LGIB with a high diagnostic yield. Besides IBD, CLNH and RMPS are two other important pathologic entities that need to be considered in a child with LGIB.