Biliary inflammation scoring for immunoglobulin G4-related sclerosing cholangitis: an endoscopic approach with endoscopic ultrasound.

ABSTRACT

BACKGROUND AND AIMS: The differential diagnosis of immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma (CC) remains a clinical challenge. Imaging modalities play critical roles in the diagnosis of IgG4-SC. The present study aimed to evaluate the differential diagnosis of IgG4-SC and CC based on images of endoscopic ultrasound (EUS). METHODS: The biliary inflammation scoring (BIS) method for EUS was developed based on the comparison between images of IgG4-SC and that of cholangiocarcinoma (CC) and other acute or chronic cholangitis. In the BIS diagnostic phase, the EUS images from 66 IgG4-SC patients and 44 CC patients were blindly evaluated using the BIS methods. RESULTS: The sensitivity, specificity, and accuracy of the newly established BIS in distinguishing IgG4-SC from CC were 86% [95% confidence interval (CI) 75-93%], 95% (95% CI 83-99%), and 90% (95% CI 83-94%), respectively. CONCLUSION: EUS should be considered to be added to the workup algorithm in patients with suspected IgG4-SC as a useful diagnostic procedure. BIS is a promising diagnostic method to discriminate IgG4-SC during the ongoing endoscopy.