De novo autoimmune hepatitis associated with PTH(1-34) and PTH(1-84) administration for severe osteoporosis in a liver transplant patient.

De novo autoimmune hepatitis (AIH) is a rare graft dysfunction occurring in patients having undergone liver transplantation (LT) for causes other than AIH. We describe for the first time a case of de novo AIH associated with the administration of parathyroid hormone 1-34 [PTH(1-34)] and PTH(1-84) for severe osteoporosis. A 61-year-old woman was referred to our metabolic bone clinic due to severe osteoporosis, 3 years after LT for primary biliary cirrhosis. Initial treatment with PTH(1-34) led to asymptomatic hypertransaminasemia (two-fold the upper limit of normal), which normalized after drug discontinuation. A new flare of transaminases (three-fold the upper limit of normal) along with elevated alkaline phosphatase was observed after administration of PTH(1-84), which did not resolve after PTH(1-84) withdrawal. Subsequently, after exclusion of common causes of liver enzyme elevation, a liver biopsy was performed. Histological findings showed de novo AIH, which responded rapidly to treatment with methylprednisolone.