対麻痺をきたした胸髄アスペルギルス症の1剖検例

Aspergillosis Involving the Thoracic Spinal Cord : An Autopsy Case

　63歳の男性が背部痛をきたし，両肺上葉の浸潤影と左S1＋2にfungus ball（FB）を認め，喀痰からAspergillus fumigatus（AF）が培養され，半年後心窩部以下の横断性麻痺，直腸膀胱障害がみられた。MRIでは第2胸椎，椎体周囲の浸潤影が脊椎管内へ広がっていた。呼吸困難が増強し，入院後11カ月で死亡した。剖検により左肺空洞内のAFは胸椎から脊髄硬膜下へ浸潤し，脊髄は著しいmyelomalaciaをきたしており，硬膜下膿瘍に伴う循環障害も発症に関与していると考えられた。

A 63 year old male complained of persistentbackache and productive cough. The chest X-ray revealed the fungus ball at the left apical-posterior segment and Aspergillus fumigatus was cultured from the sputum. He was treated on fulconazole and miconazole. Six months later, motor and sensory paralysis below the mamillary level and urinary and stool incontinence developed. A magnetic resonance image disclosed the destruction of the second tho-racic spinal vertebra involved by the cavitated fun-gus ball of the left lung. Continunous peroral admi-nistration of antifungal drugs was not successful, and he expired with severe dyspnea.

The autopsy revealed an extensive granulo-matous and purulent change of the epidural and sub-dural spaces of the second to fifth thoracic spinal cord. Subdural inflammation extended to the lower thoracic and lower cervical level. Thoracic spinal cord revealed an extensive myelomalacia predo-minantly involving the left lateral white column, and also anterior and posterior columns. Small areas of the white matter were cystic. The left anterior horn cells revealed severe central chromato-lysis. Moderate lymphocytic and plasma cell infilt-ration was found around the vessels within the cord. A few thrombi were found in the vein near the ante-rior nerve root.

Central nervous system involvement of pulmo-nary aspergillosis is quite uncommon. However, there are a few reports of patients with paraplegia secondary to the spinal extension by aspergillus infection. Sheth et al. described that epidural and subdural granulomatous change with aspergillus abscesses and spinal cord myelomalacia is compa-rable to metastatic carcinoma. However, the asper-gillus infection in the spinal cord is more extensive and destructive. Ischemic change due to venous thrombi can also play a part for the development of myelomalacia.