We read with great interest the study of Olindo et al1 about the natural history of human T-lymphotropic virus 1 (HTLV-1)–associated myelopathy/tropical spastic paraparesis (HAM/TSP). The authors followed up a cohort of patients for 14 years and recorded important landmarks in the disease evolution, such as the ability to walk with unilateral or bilateral support, restriction to a wheelchair, and death related to the disease. They also measured the HTLV-1 proviral load in peripheral blood mononuclear cells at time of diagnosis. It was shown that the progression of the motor disability continues throughout the course of disease and that a high HTLV-1 proviral load and an older age at onset adversely affect the outcome. Sex had no influence on the progression of the motor complaints.
Lima MA, Leite AC, Silva MT, Araújo AQ. Other Important Aspects of Human T-Lymphotropic Virus 1–Associated Myelopathy. Arch Neurol. 2007;64(7):1059. doi:10.1001/archneur.64.7.1059-a