Comparison of serological markers of inflammatory bowel disease with clinical diagnosis in children

Background: Our purpose was to study the concordance of serological tests for inflammatory bowel disease with clinical diagnosis established by traditional testing in children, Methods: All children seen in our division who had IBD Diagnostic System (ie, pANCA, ASCA IgA, and ASCA IgG) performed over a 21-month period (June 1998 to February 2000) were identified. Their medical records were reviewed for basic demographics, test results (endoscopy, histology, and radiology), IBD Diagnostic System results, and patient symptoms/medications. Results of the IBD Diagnostic System were compared with several patient characteristics including age, sex, absence/presence of symptoms, medication use, disease activity and duration. Results: One hundred seven patients were divided into 6 groups based on clinical diagnosis and IBD Diagnostic System results. The sensitivity, specificity and +/- predictive values of the IBD Diagnostic System for ulcerative colitis were 69.2, 95.1, 90.0, and 87.1%, respectively, and for Crohn's disease were 54.1, 96.8, 90.9, and 80.8%, respectively. Overall, the results of the IBD Diagnostic System were concordant with the clinical diagnosis in 76 of the 107 (71%) patients. Conclusions: In our experience, the specificity of IBD Diagnostic System is better than the sensitivity; the sensitivity is better for ulcerative colitis than Crohn's disease (69.2% vs 54.1%). The low sensitivity, especially for Crohn's disease, precludes the possibility that the IBD Diagnostic System can replace traditional studies when evaluating for inflammatory bowel disease. Though we do not exclude inflammatory bowel disease solely by I BD Diagnostic System results, it is reassuring to note that all patients without clinical evidence of inflammatory bowel disease also had negative IBD Diagnostic System results.