Objectives: Pediatric inflammatory bowel disease (IBD) often presents insidiously and standard blood tests are normal in 20% of patients. We hypothesize that fecal occult blood testing (FOBT) and the perianal examination in addition to blood tests provide important information during the screening process for IBD. The aim of the present study was to measure the diagnostic value of adding FOBT and perianal examination to standard screening laboratories in evaluating children and adolescents for IBD.
Methods: The medical records of consecutive patients undergoing ileocolonoscopy for IBD were reviewed. Laboratory test results, FOBT, and perianal examination before the decision to perform the ileocolonoscopy were recorded. Standard limits of laboratory tests were used. Multivariate logistic regression was performed on a discovery cohort and applied to an independent validation cohort.
Results: The discovery cohort included 335 patients (85 IBD and 250 non-IBD). A total of 61.2% had FOBT and perianal examination performed before the decision to perform the ileocolonoscopy. A total of 119 patients had complete blood testing, FOBT, and perianal examination available for full analysis. The sensitivity of the laboratory testing was 80.5% for IBD, and the sensitivity of FOBT with perianal examination was 66.9%. The combined sensitivity of laboratory testing and FOBT with perianal examination was, however, 97.6%. The most predictive model included C-reactive protein, platelet counts, and FOBT with perianal examination and was superior to the laboratory value-only model (P < 0.001) that was validated in a separate cohort.
Conclusions: Perianal examination and FOBT improve sensitivity in screening children for IBD.