Background/aims: This study aims at describing the natural history and outcome of small duct primary sclerosing cholangitis (PSC).
Methods: Thirty-two patients with small duct PSC were studied. The average time taken for diagnosis was 69 (1-168) months. The median follow-up time was 63 (1-194) months.
Results: All patients including one who underwent liver transplantation because of end-stage liver disease and hepatocellular carcinoma were alive at follow-up. None developed cholangiocarcinoma. In 27 patients repeated cholangiographic examinations were done after a median time of 72 (12-192) months from first ERCP. Four developed features of large duct PSC.
Conclusions: Small duct PSC rarely progresses to large bile duct PSC and it seems to have a benign course in most patients and no development of cholangiocarcinoma was found.