Abstract
RATIONALE: Acquired inhibitors of coagulation are antibodies that either inhibit the activity or increase the clearance of a clotting factor. Acquired factor V deficiency is a rare coagulation disorder, and it can sometimes be life threatening. PATIENT CONCERNS: We describe a case of a 90-year-old Japanese male with acquired factor V deficiency. He was previously misdiagnosed with congenital factor V deficiency when he presented with hemoptysis and a negative factor V inhibitor test result at a different hospital 5 years earlier. Coagulopathy recurred with ecchymosis when he sustained a bruise after falling on a bush. DIAGNOSIS: Although the factor V inhibitor test result was negative and a mixing study suggested a deficiency pattern, we diagnosed the patient with acquired factor V deficiency on the basis of no history of bleeding diathesis, a lack of response to multiple fresh frozen plasma transfusion, and clinical response to corticosteroid therapy. INTERVENTIONS: Intravenous methylprednisolone was administered at 500 mg/day for 3 days, followed by oral prednisolone at 1 mg/kg/day. OUTCOMES: Coagulation test results improved and symptoms resolved 2 weeks after corticosteroid administration. LESSONS: This case report suggests that clearance-facilitating antibodies exist without the presence of neutralizing inhibitors. When patients present with coagulation factor V deficiency in the absence of coagulation inhibitors, acquired factor V deficiency should also be considered.