[Familial antithrombin III abnormality accompanied with progressing ischemic stroke].

We report a case of familial antithrombin III (AT-III) abnormality accompanied with progressing ischemic stroke. The patient was a 31-year-old female who developed consciousness disturbance and left hemiparesis on December 1 in 1987. She had a history of two transient ischemic attacks and three episodes of thrombophlebitis of the extremities. Cerebral CT scan showed a low density area on the right temporal lobe that had extended to the right parietal and on the left frontal lobe as clinical symptoms worsened. Cerebral angiogram revealed branch occlusions of the right middle cerebral artery and showed no cerebral venous and sinus obstruction. When her symptoms had been progressing to show semi-comatose state, left hemiplegia and transient Cheyne-Stokes respiration, we found her decreased biological activity and normal immunological level of AT-III. The diagnosis of familial AT-III abnormality had been made by familial investigation. As the treatment of AT-III concentrates transfusion was started from the third day, her symptoms gradually recovered and the low density area stopped extending. Further examinations revealed that she was a homozygote of AT-III abnormality presenting no affinity for heparin and that her parents were heterozygotes. It was suggested that the homozygous AT-III abnormality was the main cause of her progressing ischemic stroke.