Investigação do comprometimento cognitivo no vírus linfotrópico de células T humanas tipo 1

Abstract

Human T-cell leukemia virus type-I (HTLV-1) infects around 15 to 20 million people worldwide and is a causal agent of a broad clinical spectrum of diseases. The HTLV associated myelopathy/ Tropical Spastic Paraparesis (HAM/TSP) is the most significant expression of this infection. It is associated with degeneration of white matter in the spinal cord and in brain, where perivascular inflammation in white matter region mimics lesions promoted by HIV. Considering the similarities with HIV and the subcortical location of the lesions, neuropsychiatric symptoms and cognitive damage are supposed to occur. The aim of this study is to investigate the existence of cognitive impairment associated to HTLV-1 infection and evaluate if it has any correlation with the degree of neurological disability of patients. Neuropsychological assessment was conducted in an experimental and a control group matched for age, sex and education. Functional performance and depressive symptoms were also evaluated in both groups. We found a lower performance of HTLV-1 patients on measures of motor processing, verbal memory, executive functions, depressive symptoms and functional performance, when compared with controls. In cognitive measures, HTLV-1 subgroups showed no significant difference among them; however, symptomatic subgroups showed significantly more depressive symptoms and were less functional than asymptomatic carriers. Depression was not correlated with any of the deficits assigned to the infection. These results suggest the presence of important cognitive impairment in HTLV-1 patients, including asymptomatic carriers. We concluded that HTLV-1 asymptomatic infection is not a benign condition, but a stage of the disease temporally coursing with less symptoms.