産褥期に血小板増多と線溶系亢進を伴い，予後良好な前脊髄動脈症候群を呈した1例

A Case of Benign Postpartum Anterior Spinal Artery Syndrome with Thrombocytosis and High Fibrolytic Activity

はじめに

　前脊髄動脈症候群は，前脊髄動脈に支配される脊髄の前方約2/3の領域内に血流障害が生じ，その結果脊髄症が出現するものである。急速に発現する対麻痺または四肢麻痺，障害レベル以下の解離性感覚障害，早期から出現する膀胱直腸障害が特徴とされている¹⁾。脳血管障害とは異なり動脈硬化の関与は少ないとされ，発症年齢も若年から高齢までさまざまである¹⁾。解離性大動脈瘤など脊髄外血管の閉塞がその原因として頻度が高い¹⁾とされるが，血液凝固異常によって発症する場合もある²⁾。一方で，周産期の母体は血液凝固亢進の傾向にあり，血栓塞栓症が出現しやすいことが報告されている³⁾。今回われわれは，産褥期に血小板増多と線溶系亢進を伴い，前脊髄動脈症候群が出現した例を経験したので報告する。

Abstract

　A 35-year-old woman was admitted to our hospital with acute onset paraparesis, sensory disturbance in her lower body, and urinary disturbance.　She had given birth by normal vaginal delivery 6 days before the onset of these symptoms.　On admission, paresis of her left leg was more severe than that of her right leg.　Deep tendon reflexes of her lower limbs were hyperactive, and bilateral Babinski reflexes were observed.　The patient's thermal and pain sensations below the lumbus were impaired.　She lost bladder-filling sensation and bladder control.　She showed an anterior spinal artery syndrome.　Blood analysis revealed thrombocytosis and high fibrolytic activity.　MRI of the brain and spinal cord did not show any lesions.　Cerebrospinal fluid measurements showed that parameters were within the normal range and that the protein levels were not increased.　We considered that a spinal cord infarction had occurred.　After administration of antithrombotic agents and methylpredonisolone, her symptoms gradually improved.　The coagulation disorders during the peripartum period were assumed to be a cause of anterior spinal artery syndrome in this case.　It is very rare for perinatal women to have a spinal cord infarction.　Only 3 cases of spinal cord infarction during the perinatal period have been reported thus far.

(Received: January 12,2011,Accepted: March 3,2011)