Small-duct primary sclerosing cholangitis.

Patients with cholestatic liver tests and typical histologic features of primary sclerosing cholangitis (PSC) but a normal cholangiogram have been identified as having small-duct PSC. This subgroup of PSC has been less well characterized than the classic large-duct form. Some patients characterized as having small-duct PSC develop cholangiographic features of PSC during follow-up. Three papers published in 2002 on small-duct PSC patients suggested a better prognosis in patients with small-duct PSC than in those with large-duct PSC. However, these studies included a limited number of patients and had a short follow-up. A combined cohort of these patients with a prolonged follow-up recently confirmed these previous observations. However, some patients will suffer from liver-related mortality or will need to undergo liver transplantation. Recurrence of small-duct PSC after liver transplantation has been reported. Cholangiocarcinoma, the most feared complication of PSC, has not been described in a patient with small-duct PSC without progression first to large-duct PSC.