An autopsy case of human T-lymphotropic virus type I-associated myelopathy.

This report describes the first autopsy case of human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM). The disease mainly affected the spinal cord, particularly the lateral and anterior columns, where loss of myelin and axon was observed. The changes were bilateral and occurred mainly along the tract. Perivascular and parenchymal infiltration with lymphocytes and macrophages, as well as astrocytosis, were observed in the white and grey matters of the spinal cord. Blood vessels in the spinal cord and in the subarachnoid space of the spinal cord showed hyalinoid thickening of media and adventitia associated with infiltration of lymphocytes. These findings are similar to those of tropical spastic paraparesis (TSP).