特発性血小板減少性紫斑病に合併した脊髄硬膜外血腫の1例

A Case of Spinal Epidural Hematoma Associated with Idiopathic Thrombocytopenic Purpura

I．はじめに

　脊髄硬膜外血腫は比較的稀な疾患で，現在まで本邦では29例の報告をみるに過ぎない．本症は発生機序から特発性と二次性に分けられているが^17），最近，私たちは特発性血小板減少性紫斑病（Idiopathic thrombocyto—penic purpura以下ITPと略す）に合併した二次性の脊髄硬膜外血腫を経験した．ITPに合併した脊柱管内出血例として脊髄出血の1例^3）が報告されているが，脊髄硬膜外血腫の報告はなく，極めて稀な症例と考え，若干の文献的考察を加えて報告する．

Spinal epidural hematoma is a rare clinical entity, and the literature provides reports of 29 cases so far in japan. A case of spinal epidural hematoma associatedwith idiopathic thrombocytopenic purpura diagnosed by CT scan and MRI is reported in detail with refer-ences to the literature.

A 56-year-old female was admitted to our hospital on April 22, 1990, because of sudden onset of nuchal pain and right hemiparesis. Her consciousness was alert, but the deep tendon reflex was depressed, and pathological reflex such as Babinski's reflex was positive on the right side. Nuchal stiffness was observed. CT scan of the head revealed no abnormality, but the scan of cer-vical area showed an abnormal high density area in the right posterior region of the spinal cord at C2 - 3 level. MRI also revealed a low intensity area in the same re-gion both in Tl and T2 weighted images. On admission, the platelet count was 10,000/μl, and the bone marrow aspirate showed abundant megakaryocytes. The patient was diagnosed as having spinal epidural hematoma associated with idiopathic thrombocytopenic purpura. The patient was initially treated with a corticosteroid and a hyperosmotic agent. About 15 hours after the onset, her motor function began improving. Conserva-tive therapy was continued, and she could walk 2 weeks after the onset.

Spinal epidural hematoma is an uncommon disease commencing with back and radicular pain, paraplegia and rectovescical insufficiency. Early diagnosis and sur-gical decompression is generally imperative, although an exceptional remission without operation such as was observed in this case may occur.