Human T-cell lymphotropic virus type I and neurologic disease in Panama, 1985 and 1986

F. Gracia, W. C. Reeves, P. H. Levine, M. Cuevas, L. Castillo, R. Chavarria, V. Grimaldo, E. Triana, J. R. Arosemena and W. A. Blattner
Neurology Service, Santo Tomas Hospital, Panama City, Panama.

Human T-cell lymphotropic virus type I (HTLV-I) causes adult T-cell leukemia and has recently been associated with HTLV-associated myelopathy/tropical spastic paraparesis. The HTLV-I is endemic throughout the Caribbean basin and parts of South America, and HTLV-associated myelopathy/tropical spastic paraparesis also seems to be common in this area. This 2-year study, 1985 and 1986, was designed to evaluate the occurrence of HTLV-I infection in all newly diagnosed cases of selected neurologic diseases in Panama City, Panama. Six (8%) of 71 patients had antibody to HTLV-I detected by immunofluorescence, enzyme-linked immunosorbent assay, radioimmunoassay, and Western blot assays; 5 patients' conditions were diagnosed as spastic paraparesis, and all 5 were seropositive and also had HTLV-I antibody in cerebrospinal fluid. The remaining seropositive patient had multiple sclerosis, and no antibody was detected in her cerebrospinal fluid. Clinical and electrophysiologic studies indicated that HTLV-I-associated spastic paraparesis is a multifocal, primarily demyelinating disease that principally involves the spinal cord.