LKM-positive autoimmune hepatitis in the western United States: A case series

OBJECTIVE: LKM-positive, or type 2, autoimmune hepatitis is characterized b y the presence of antibodies directed against liver-kidney microsomes (LKM1 ). Although described frequently in southern Europe and the Mediterranean, this subtype of autoimmune liver disease seems to be extremely rare in nort hern Europe and in the United States. We report here five cases of LKM-posi tive autoimmune hepatitis that were seen at our center in the period 1989-1 999. METHODS: We reviewed the medical records of all patients with the diagnosis of AIH in our institution during the period 1989-1999, and found that five patients had type 2 AIH. All patients were female; four of five were young , and four of five presented with overt cirrhosis. RESULTS: One patient died, one underwent liver transplantation and two are currently awaiting liver transplantation. Response to conventional immunosu ppressive therapy was poor and two patients required treatment with cyclosp orine and tacrolimus respectively. Four of five patients had at least one a ssociated autoimmune disorder, including IgE-induced IgA deficiency, idiopa thic thrombocytopenic purpura (ITP), and arthritis. HLA class II DR4 was pr esent in two patients. CONCLUSIONS: LKM-positive autoimmune hepatitis seems to be a Subset of auto immune hepatitis with distinct clinical features; although rare, it is occa sionally encountered in the western United States. Prompt diagnosis and app ropriate immunosuppressive treatment are recommended, as well as early refe rral to transplantation centers. Clinicians should be aware of this conditi on in the setting of young female patients with unexplained severe liver di sease. (C) 2000 by Am. Cell. of Gastroenterology.