Patients who have abnormal blood tests and a liver biopsy which shows features consistent with a diagnosis of PSC but who have a normal MRCP or ERCP (cholangiogram) are described as having small-duct PSC.
6-16% of the PSC population have small duct disease. For the most part, the course of their disease is milder than for large-duct disease with fewer symptoms and a favourable prognosis with regard to survival, need for transplantation and the chance of development of cholangiocarcinomais extremely small.
Reviewed 10/05/12Taken from Chapman, 2011. Primary sclerosing cholangitis. Medicine,39(10): 588-591