title: 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.
abstract: 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.
authors.affiliation: Departamento de Patologia, Análises Clínicas e Toxicológicas, Centro de Ciências da Saúde, Universidade Estadual de Londrina, Paraná, Brasil.
authors.forename: Helena Kaminami
authors.initials: HK
authors.lastname: Morimoto
authors.forename: Arilson Akira
authors.initials: AA
authors.lastname: Morimoto
authors.forename: Edna Maria Vissoci
authors.initials: EM
authors.lastname: Reiche
authors.forename: Luiz Toshio
authors.initials: LT
authors.lastname: Ueda
authors.forename: Tiemi
authors.initials: T
authors.lastname: Matsuo
authors.forename: Fernando Vissoci
authors.initials: FV
authors.lastname: Reiche
authors.forename: Adele
authors.initials: A
authors.lastname: Caterino-de-Araujo
mesh_terms: D015153:Blotting, Western; D001938:Brazil / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004279:DNA, Viral / Q000302:isolation & purification; D015752:Genes, env / Q000235:genetics; D015658:HIV Infections / Q000150:complications*; D015481:HTLV-I Antibodies / Q000097:blood; D015490:HTLV-I Infections / Q000175:diagnosis* / Q000453:epidemiology; D015482:HTLV-II Antibodies / Q000097:blood; D015491:HTLV-II Infections / Q000175:diagnosis* / Q000453:epidemiology; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000276:immunology; D015367:Human T-lymphotropic virus 2 / Q000235:genetics / Q000276:immunology; D006801:Humans; D007124:Immunoenzyme Techniques; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015995:Prevalence; D012680:Sensitivity and Specificity