Characteristics of primary sclerosing cholangitis in Japan

Abstract

At a workshop on primary sclerosing cholangitis (PSC) held during Digestive Disease Week - Japan 2003, 388 PSC cases in Japan were analyzed. Two peaks in the age distribution were also observed in this survey. Jaundice and itching, major symptoms in PSC patients included in the diagnostic criteria, were observed in only 28% and 16%, respectively. Alkaline phosphatase levels were less than twofold of the upper limit of the normal range in 35%. In this regard, the diagnostic criteria in 2003 from the Mayo Clinic, including cholestatic symptoms and two- to threefold increases in serum alkaline phosphatase, should be modified in Japan. Inflammatory bowel diseases were complicated in 37%, and autoimmune pancreatitis (AIP) in 7.2%. PSC cases with inflammatory bowel diseases were younger than the average, creating the firstpeak in age distribution, and have similar characteristics compared to patients with PSC in foreign countries. In addition, even after the exclusion of cases of sclerosing cholangitis complicated with AIP, the second peak in the age distribution was clearly evident. Recently, a concept of immunoglobulin G4-related sclerosing cholangitis has been postulated, which has a similar pathogenesis to AIP but without apparent pancreatic lesions. PSC patients without apparent involvement of the pancreas may be present in older patients and seem to be specific to Japan.