Acquired factor VIII inhibitor associated with chronic untreated hepatitis C

Acquired inhibitors of coagulation are antibodies that either inhibit the activity or increase the clearance of a clotting factor. A hemorrhagic diathesis is a common clinical manifestation in affected patients. Acquired factor VIII inhibitor – or acquired hemophilia A – is a rare disorder and presents similarly to hemophilia A, though patients are less likely to develop hemarthroses. This inhibition is most commonly due to autoantibodies against coagulation factor VIII. These autoantibodies often occur in pregnancy, autoimmune disorders, solid tumors, and lymphoproliferative syndromes. Several drugs, including penicillins, phenytoin, and sulfa drugs, have also been associated with antibodies to factor VIII. Chronic infection with the hepatitis C virus (HCV), in addition to various degrees of liver inflammation and fibrosis, can have extrahepatic manifestations, especially autoimmune disorders. The most common hematological complications of HCV infection are thrombocytopenia, cryoglobulinemia, and anti-cardiolipin antibodies. A few cases of factor VIII inhibitors occurring in HCV patients have been reported, with a higher incidence after prolonged treatment with interferon-α. Here, we present a case of a patient with chronic untreated HCV infection developing acquired factor VIII deficiency.