Variant forms of cholestatic diseases involving small bile ducts in adults

Cholestasis may result from diverse etiologies. We review chronic cholestatic disorders involving small intrahepatic bile ducts in the adult ambulatory care setting. Specifically, we discuss variant forms of primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) as well as other conditions that may present diagnostic and therapeutic difficulties.

We conducted a MEDLINE search of the literature (1981-1997) and reviewed the experiences at the Mayo Clinic. All articles were selected that discussed antimitochondrial antibody (AMA)-negative PBC, small-duct PSC (formerly pericholangitis), and idiopathic adulthood ductopenia.

The most common chronic cholestatic liver diseases affecting adults are PBC and PSC. Patients without the hallmarks of either syndrome are diagnosed according to their clinical and histological characteristics. Autoimmune cholangitis is diagnosed if clinical and histological features are compatible with PBC but autoantibodies other than AMA are present. Isolated small duct PSC is diagnosed if patients have inflammatory bowel disease, biopsy features compatible with PSC, but a normal cholangiogram. If ductopenia (absence of interlobular bile ducts in small portal tracts) is found histologically in the absence of PSC, inflammatory bowel disease, and other specific cholestatic syndromes such as drug reaction or sarcoidosis, the most likely diagnosis is idiopathic adulthood ductopenia.

Based on these definitions, an algorithm for diagnosis and therapy in patients with laboratory evidence of chronic cholestasis may be constructed, pending results of further investigations into the etiopathogenesis of these syndromes.