Perfil soroepidemiológico e molecular das infecções pelos vírus linfotrópicos de células t humanas 1 e 2 em grupos populacionais em Goiânia, Goiás

Abstract

Human T-cell lymphotropic virus type 1 (HTLV-1) is the etiological agent of major diseases such as adult T-cell leukemia/lymphoma (ATL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and other inflammatory diseases. HTLV-2 has been associated with a syndrome similar to HAM/TSP and increased incidences of respiratory and urinary tract infections, but these associations are not well defined. This study aimed to assess the prevalence of HTLV-1 and 2 in three selected groups: patients with tuberculosis, HIV seropositive treatment-naive individuals and patients with oncohematological diseases in Central Brazil, and also to carry out genetic characterization of respective isolates. A total of 1,252 individuals in Goiânia-GO were studied, included 402 patients with tuberculosis (group I), 505 HIV seropositive treatment-naive individuals (group II) and 345 patients with oncohematological diseases (group III). All subjects were interviewed and blood samples were tested by enzyme-linked immunosorbent assay (ELISA) for the presence of HTLV antibodies. Positive samples were tested for confirmation by polymerase chain reaction (PCR) and nucleotide sequencing. Sixteen samples were positive by ELISA, including six from the group I, four from the group II and six from the group III; of these, 12 were confirmed as positive by PCR, resulting in an HTLV-1/2 prevalence of 1.24% (CI 95%: 0.46-2.01), 0.79% (CI 95%: 0.25-2.16) and 0.87% (95% CI: 0.22-2.73), respectively. Sequencing analysis demonstrated that all HTLV-1 isolates (four in the group I, four in the group II and three in the group III) belonged to the Cosmopolitan subtype HTLV-1a Transcontinental subgroup A. The single HTLV-2 isolate was from a patient with tuberculosis, and it was classified as subtype a (HTLV-2 a/c). Most HTLV-1 infected patients reported sexual risk behaviors, and the HTLV-2 positive individual reported in addition to sexual risk behaviors, injection drug use. The prevalence rates found in this study are higher than that found in blood donors (0.13%; CI 95%: 0.11-0.17) in Goiânia, and HTLV-1 and 2 subtypes identified in this study were consistent with those circulating in Brazil.