[Mild hemophilia A diagnosed at the onset of acute epidural hematoma after lumbar epidural block].

The patient was a 36-year-old man who had been aware of a mild bleeding tendency since childhood, but did not show any history of severe bleeding. After lumbar epidural block was performed for pain caused by lumbar disc herniation, the patient developed paraplegia due to an acute epidural hematoma, and rectovesical disorder. He was admitted to our hospital, and wide fenestration and hematoma evacuation were performed. Because of persistent bleeding, reoperation was performed to achieve hemostasis. Although factor VIII antigen was 138%, its activity was decreased to 18% of normal. A diagnosis of cross-reacting material positive mild hemophilia A was made. Postoperative injection of a factor VIII preparation resulted in complete hemostasis. The activated partial thromboplastin time was within normal range. A thrombin generation test showed reduced endogenous thrombin potential, peak thrombin levels, and prolonged time-to-peak levels. The thrombin generation test, which allows comprehensive assessment of the coagulation profile, was useful for diagnosis and treatment of this case.