Evaluation of diagnostic criteria for Crohn's disease in Japan

Abstract

Background: In Japan, Crohn's disease (CD) is diagnosed according to a single, well-established set of diagnostic criteria. However, no nationwide attempt has been made to determine which specific criteria within these diagnostic criteria are used to make diagnoses.

Methods: A questionnaire-based survey was conducted of patients given a definitive or suspected diagnosis of CD before January 2011 according to the Japanese Diagnostic Criteria for Crohn's Disease. The survey included 579 patients with a definitive diagnosis of CD and 59 patients with a suspected diagnosis of CD at 34 Japanese medical institutions.

Results: A total of 87.4 % of definitive diagnoses of CD were based on the criterion in the definite category: major finding A "longitudinal ulcer (LU)" or B "cobblestone-like appearance (CSA)". A total of 30.4 % of definitive diagnoses were based on the criterion: major finding C "non-caseating epithelioid cell granuloma (NCEG)" with minor finding a "irregularshaped and/or quasi-circular ulcers or aphthous ulcerations found extensively in the gastrointestinal tract" or b "characteristic perianal lesions". Finally, 7.1 % of definitive diagnoses were made according to the criterion: all minor findings a, b and c "characteristic gastric and/or duodenal lesions". Among suspected diagnoses of CD, 74.6 % were based on the criterion in the suspected category: one or two minor findings.

Conclusions: The Japanese diagnostic criteria for Crohn's disease consist of combinations of specific morphological findings. Many of the diagnoses were based on the findings of LU or CSA.