Human T-cell lymphotropic virus-type I.

HTLV-I is a retrovirus now identified as the etiologic agent of two diverse disease processes: ATLL, an aggressive T-cell malignancy; and TSP/HAM, a chronic progressive myelopathy. Transmission can occur horizontally through blood transfusions, IV drug abuse and sexual intercourse. Vertical transmission may also occur. Available diagnostic modalities are serologic in nature and include the EIA and the more specific confirmatory assays WIB and RIPA. These studies are thus far suboptimal in terms of sensitivity and specificity, and await refinement. DNA amplification by the polymerase chain reaction seems to hold the most immediate diagnostic promise for the future. AZT apparently is not useful clinically, and current treatment is only palliative in nature. The diverse diseases caused by HTLV-I underscore the insidious nature of the Retroviridae family. These subtle cell-associated pathogens will undoubtedly be shown to play a significant role in other disease processes of uncertain etiology.