Concurrent de novo autoimmune hepatitis and recurrence of primary biliary cirrhosis post-liver transplantation.

Primary biliary cirrhosis (PBC) is well known to recur after liver transplantation (LT). The recurrence is usually subclinical and evident only on histological examination. Recently, a new entity of de novo autoimmune hepatitis (AIH) has emerged that occurs after LT in patients who underwent transplantation for diseases other than AIH. This new condition occurs more often in children; however, there was a recent report of the first 2 cases in adults who originally underwent LT for PBC. We report the first case of concurrent de novo AIH and recurrence of PBC documented on the liver biopsy of an adult patient who underwent LT for end-stage PBC. Unlike the earlier report of 2 adults, our patient manifested an antinuclear antibody titer of more than 1/800 from a previously negative titer pre-LT, as well as fulfilled the International AIH Group criteria for a definite diagnosis of AIH. PBC recurrence was evidenced by typical florid duct lesion, antimitochondrial antibody titer increasing from 1/40 to greater than 1/800, and an elevated serum immunoglobulin M level. After the addition of azathioprine to baseline immunosuppression of tacrolimus and prednisolone, the patient responded rapidly, with complete normalization of liver test results.