Retrovirus-associated myelopathies
G. C. Roman
Human T-lymphotropic virus type I (HTLV-I), the causative agent of adult
T-cell leukemia and non-Hodgkin's lymphoma (ATLL)--or a cross-reacting
retrovirus--has been associated with tropical spastic paraparesis in
Martinique, Jamaica, Colombia, Trinidad and Tobago, the Seychelles, and
probably also in Zaire. The Caribbean basin and sub-Saharan Africa are
endemic for ATLL. A similar etiology has been invoked in a chronic spastic
myelopathy occurring in areas of high ATLL endemicity in Japan. An HTLV-I
viral antigen has been demonstrated in cerebrospinal fluid lymphocytes of a
Japanese patient with myelopathy. Human T-lymphotropic virus type I
antibodies have occurred in patients in Florida and Japan (areas of HTLV-I
endemicity) who were diagnosed as having clinically definite multiple
sclerosis (MS), but not in patients with MS in other parts of the world.
Human T-lymphotropic virus type I, like some lentiviruses--visna and human
immunodeficiency virus, in particular--may be both lymphotropic and
neurotropic. Tropical spastic paraparesis, the Japanese myelopathy, and,
perhaps, an MS-like neurologic syndrome, may represent clinical variants of
the same disease, a retroviral myelopathy.
