Use of amplified Mycobacterium tuberculosis direct test in respiratory samples from HIV-infected patients in Brazil

OBJECTIVE: To compare the accuracy of the amplified Mycobacterium tuberculosis direct (AMTD) test with reference methods for the laboratory diagnosis of tuberculosis in HIV-infected patients. METHODS: This was a study of diagnostic accuracy comparing AMTD test results with those obtained by culture on Löwenstein-Jensen (LJ) medium and by the BACTEC Mycobacteria Growth Indicator Tube 960 (BACTEC MGIT 960) system in respiratory samples analyzed at the Bioassay and Bacteriology Laboratory of the Oswaldo Cruz Foundation Evandro Chagas Clinical Research Institute in the city of Rio de Janeiro, Brazil. RESULTS: We analyzed respiratory samples collected from 118 patients, of whom 88 (74.4%) were male. The mean age was 36.6 ± 10.6 years. Using the AMTD test, the BACTEC MGIT 960 system, and LJ culture, we identified M. tuberculosis complex in 31.0%, 29.7%, and 27.1% of the samples, respectively. In comparison with LJ culture, the AMTD test had a sensitivity, specificity, positive predictive value, and negative predictive value of 87.5%, 89.4%, 75.7%, and 95.0%, respectively, for LJ culture, whereas, in comparison with the BACTEC MGIT 960 system, it showed values of 88.6%, 92.4%, 83.8%, and 94.8%, respectively. CONCLUSIONS: The AMTD test showed good sensitivity and specificity in the population studied, enabling the laboratory detection of M. tuberculosis complex in paucibacillary respiratory specimens

Molecular epidemiology of HIV-1 in Brazil: high prevalence of HIV-1 subtype B and identification of an HIV-1 subtype D infection in the city of Rio de Janeiro, Brazil. Evandro Chagas Hospital AIDS Clinical Research Group.

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2014-08-12T17:52:20Z No. of bitstreams: 1 Morgado MG Molecular epidemiology of HIV.....pdf: 103327 bytes, checksum: ace5ee034b28ed20364e52d7e527ca14 (MD5)Made available in DSpace on 2014-08-12T17:52:20Z (GMT). No. of bitstreams: 1 Morgado MG Molecular epidemiology of HIV.....pdf: 103327 bytes, checksum: ace5ee034b28ed20364e52d7e527ca14 (MD5) Previous issue date: 1998Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilBanco da Previdência Outpatient clinic.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, Brasil / Banco da Previdência Outpatient clinic.Fundação Oswaldo Cruz. CICT. Department of Health Information. Rio de Janeiro, RJ, BrasilLos Alamos National Laboratories. Los Alamos, New Mexico, USAFundação Oswaldo Cruz. CICT. Department of Health Information. Rio de Janeiro, RJ, Brasil / Brazilian Ministry of Health. National Coordination of STD/AIDS. Brasília, DF, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório Avançado de Saúde Pública. Salvador, BA, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Hospital Evandro Chagas. Departamento de Imunologia. Rio de Janeiro, RJ, BrasilHIV-1-positive individuals were recruited from January 1993 to December 1996 from several cohorts receiving follow-up in the city of Rio de Janeiro, Brazil, to evaluate HIV-1 genetic variability and the potential association with modes of transmission. HIV-1 subtyping was carried out using the heteroduplex mobility assay (HMA), and those samples corresponding to the typical Brazilian subtype B variant were further identified based on the Fok I restriction fragment length polymorphism (RFLP). DNA sequencing was performed to evaluate one case of subtype D infection. From the 131 HIV-1-positive individuals analyzed, 106 (80.9%) could be identified as infected by subtype B and 20 (15.3%) by subtype F. One of the samples (0.8%) was classified as subtype D. DNA samples from 4 patients (3.0%) did not yield polymerase chain reaction (PCR)-amplified products to be typed. Based on the Fok I RFLP, 39 of the 106 subtype B samples (37%) were identified as corresponding to the typical Brazilian subtype B variant containing the GWGR motif at the tip of the V3 loop. No statistically significant association could be detected between HIV-I subtypes and modes of transmission, exposure categories, or gender. This is the first reported case of HIV-1 subtype D infection in Brazi