Human T-cell lymphotropic virus types I and II infections in a cohort of patients with neurological disorders in Belém, Pará, Brazil

Abstract

Serum- and/or- cerebrospinal fluid (CSF) samples obtained from 190 patients suffering from chronic, progressive neurological disease were screened for the presence of human T-cell lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) antibodies over a six-year period (1996 to 2001) in Belém, Pará, Brazil. Patients were of both sexes (male subjects, 52%) with ages ranging from 2 to 79 years (mean, 35.9). Overall, 15 (7.9%) subjects - of whom 12 (80%) were female adults - reacted HTLV-I/II-seropositive when screened by enzyme-linked immunosorbent assay (ELISA). Serum samples from 14 of these patients were also analyzed using a recombinant Western blot (WB) assay that yielded HTLV-I-, HTLV-II-, and HTLV-I/II- reactivities for 10 (71.4%), 3 (21.4%) and 1 (7.2%) of them, respectively. The yearly rates of HTLV-I/II antibodies ranged from 2.6% (2001) to 21.7% (2000), with progressively increasing seropositivities from 1998 to 2000. Altogether, walking difficulty (n = 5 subjects), spasticity (n = 4) and leg weakness (n = 3) accounted for 80% of symptoms recorded among the 15 patients whose sera had antibodies to HTLV-I/II as detected by ELISA. These findings provide evidence that both HTLV-I and HTLV-II play a role in the development of chronic myelopathy in Belém, Pará, Northern Brazil.

Moderada endemicidade da infecção pelo vírus linfotrópico-T humano na região metropolitana de Belém, Pará, Brasil

“…Investigations into the frequency of HTLV infections in the state of Pará are specifically performed in groups of blood donors 15 , pregnant women 17 , rural communities and/ or individuals living in quilombos 18 , HIV positive people 20 and people with neurological diseases 27 . We investigated the prevalence of HTLV infection in adults passing through public places in the city of Belém, Pará, Brazil, because Pará is one of three Brazilian states with the greatest endemicity for this infection in blood donors 15 .…”

Serological patterns and temporal trends of HTLV-1/2 infection in high-risk populations attending Public Health Units in São Paulo, Brazil

“…Besides the general population, a high percentage of intravenous drug users (IVD) from urban areas of Brazil, mostly HIV-1-infected, harbor HTLV-1/2 (Barbosa de Carvalho et al, 1996;Casseb et al, 1997a;Caterino-de-Araujo et al, 1998;de Araujo et al, 1994;Etzel et al, 2001;Gabbai et al, 1993;Moreira et al, 1993;Morimoto et al, 2005;Vallinoto et al, 1998). Several diseases, including adult T-cell leukemia (ATL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), other neurological syndromes, pneumonia, arthritis, bronchitis, and dermatological and urinary diseases, are associated with HTLV-1 and/or HTLV-2 infection in Brazil Macedo et al, 2004;Montanheiro et al, 2005;Pombo de Oliveira et al, 1995;Posada-Vergara et al, 2006). Accurate diagnosis of these viruses is therefore important to ensure prompt and appropriate care of infected patients.…”

Difficulties in the diagnosis of HTLV-2 infection in HIV/AIDS patients from Brazil: comparative performances of serologic and molecular assays, and detection of HTLV-2b subtype

“…Unfortunately, for Brazilian population, commercially available serologic kits lack in confirming HTLV-2 infection, especially in HIV/ AIDS coinfected patients 6,9 . Indeed, although the controversial role of HTLV-2 in the pathogenesis of several diseases, an association of neurological syndromes, pneumonia, bronchitis and arthritis, have been documented in HTLV-2-infected patients, as well as cutaneous lymphoma in few cases of HIV/HTLV-2 co-infected patients [3][4]21,28 . Paradoxically, antiretroviral therapy increases HTLV-2 proviral load, and may alter the course of HIV disease 22,25 .…”