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 Dificuldades no diagnóstico de infecção por HTLV-2 em pacientes com HIV/Aids do Brasil: análise comparativa de ensaios sorológicos e moleculares e detecção de subtipo HTLV-2b

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Helena Kaminami Morimoto, Arilson Akira Morimoto, Edna Maria Vissoci Reiche, Luiz Toshio Ueda, Tiemi Matsuo, Fernando Vissoci Reiche, Adele Caterino-de-Araujo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2007
• Subjects: Human T-lymphotropic virus type 2 (HTLV-2); HIV/HTLV-2 coinfection; Diagnosis; Serology; PCR; HTLV-2 subtype; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; Eia; Mercado
• Online Access: https://doi.org/10.1590/S0036-46652007000400006; https://doaj.org/article/a57b340fe58c4c9db2201bbdbec21016

The current diagnosis of human T-lymphotropic virus type-2 (HTLV-2) infection is based on the search of specific antibodies; nevertheless, several studies conducted in Brazil pointed deficiencies of the commercially available kits in detecting HTLV-2, mostly in HIV/AIDS patients. This study searched for the presence of HTLV-1 and -2 in 758 HIV/AIDS patients from Londrina, Paraná, Brazil. Serum samples were screened for HTLV-1/2 antibodies using two EIA kits (Vironostika and Murex), and confirmed by WB (HTLV Blot 2.4, Genelabs). The results obtained by EIA disclosed 49 (6.5%) reactive sera: 43 positive by both EIA kits, and six with discordant results. WB confirmed HTLV-1 infection in seven samples (0.9%) and HTLV-2 in 21 sera (2.8%). Negative and indeterminate results were detected in four (0.5%) and 16 (2.1%) sera, respectively. Blood from 47 out of 49 HTLV seroreactive patients were collected and analyzed for the presence of env, LTR and tax genomic segments of HTLVs by PCR. PCR confirmed six cases of HTLV-1 and 37 cases of HTLV-2 infection (14 out of 16 that were found to be WB indeterminate). Restriction analysis of the env PCR products of HTLV-2 disclosed 36 isolates of HTLV-2a/c subtype, and one of HTLV-2b subtype. These results emphasize the need of improving serologic tests for detecting truly HTLV-2 infected patients from Brazil, and confirm the presence of HTLV-2b subtype in the South of this country. O diagnóstico de infecção por HTLV-2 se baseia na pesquisa de anticorpos específicos, entretanto, vários estudos conduzidos no Brasil têm apontado falhas nos kits sorológicos disponíveis no mercado em detectar HTLV-2, principalmente nos pacientes com HIV/aids. Este trabalho avaliou a presença de infecção por HTLV-1 e -2 em 758 pacientes HIV/aids de Londrina, Paraná, Brasil. Amostras de soro foram analisadas quanto à presença de anticorpos anti-HTLV-1/2 por dois kits de EIA (Vironostika e Murex) e confirmados por WB (HTLV Blot 2.4, Genelabs). Os resultados obtidos pelos testes sorológicos mostraram 49 ...