Analysis of 388 cases of primary sclerosing cholangitis in Japan; Presence of a subgroup without pancreatic involvement in older patients.

We analyzed 388 cases of primary sclerosing cholangitis (PSC) in Japan, according to a questionnaire sent to gastroenterologists. There was male predominance (59%), and interestingly there were two peaks in the age distribution as seen in the previous study. Jaundice and itching, major symptoms in PSC patients included in the diagnostic criteria, were observed only 28 and 16%, respectively. Alkaline phosphatase level was less than twofold of the upper limit of the normal range in 35%. In this regard, the diagnostic criteria in 2003 from Mayo Clinic, including cholestatic symptoms and two to three-fold 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 first peak in the age distribution, and have similar characteristics compared to patients with PSC in foreign countries. By contrast, those with AIP, who were more than 50 years old, responded well to corticosteroid therapy. In addition, even after the exclusion of cases of sclerosing cholangitis complicated with AIP, the second peak in the age distribution was clearly evident. Therefore, we conclude that PSC patients without apparent involvement of the pancreas are present in the older patients and seem to be specific in Japan.