Comparing the simplified and international autoimmune hepatitis group criteria in primary sclerosing cholangitis

Background and aims: Although highly sensitive and specific, the revised International Autoimmune Hepatitis Group (IAIHG) diagnostic criteria for autoimmune hepatitis (AIH) are cumbersome to use in clinical practice and rely upon a number of autoantibodies that are costly and are not widely available. The simplified scoring system for AIH attempts to rectify the complexity of the IAIHG criteria. To date, there have been few studies assessing the specificity of the simplified score for AIH when applied to patients with cholestatic liver diseases. The purpose of this study was to examine the specificity of the simplified scoring system for AIH as compared to the revised IAIHG criteria in a large cohort of patients with primary sclerosing cholangitis (PSC). Methods: The patient population consisted of 147 patients enrolled in two prospective trials at the Mayo Clinic examining the use of ursodeoxycholic acid in PSC. All of the patients underwent baseline blood work (including standard serologic testing to exclude other liver diseases), liver biopsy, and cholangiogram to confirm PSC. Demographic, laboratory, and histologic data were extracted for each subject. Simplified and revised IAIHG scores were calculated for each subject and compared. Results: The simplified scoring system identified 2 patients with probable AIH and no patients with definite AIH. Comparatively, the revised IAIHG scoring system identified no patients with probable or definite AIH. Conclusion: As with the revised IAIHG criteria, the simplified scoring system for AIH has excellent specificity when applied to a PSC population.