Abstract
Acquired hemophilia A is a rare disease caused by the acquisition of factor Ⅷ inhibitor. Its incidence is reported to be 1.48 cases per million persons, and is often diagnosed on sudden bleeding of subcutaneous or intramuscular tissue. Here, we report a case of acquired hemophilia A diagnosed with submucosal hematoma of the oral cavity.
A male patient in his 70s was referred to our hospital due to growth of an oral hematoma. He did not have any prior history of bleeding. On laboratory tests, the platelet count and prothrombin time were almost normal. However, the activated partial thromboplastin time was longer than normal. We suspected coagulopathy and further examination was done. Then, a decrease in coagulation activity of factor Ⅷ and the presence of factor Ⅷ inhibitor were detected. On hospital day 5, we diagnosed him with acquired hemophilia A and began immunotherapy with prednisolone. On hospital day 16, the submucosal hematoma disappeared. On hospital day 28, factor Ⅷ inhibitor was not detected on laboratory tests. Prednisolone was gradually decreased and there are no longer any symptoms of bleeding and hematoma.
