ABSTRACT
The ability to detect HIV-2 and to discriminate between HIV-1 and HIV-2 infections was evaluated in 46 serum samples from Guinea-Bissau (GB) and Guinea-Conakry (GC) using serological tests and commercial (HIV-1) and in-house (HIV-2) real-time PCR assays. Samples were first identified as HIV-2 positive by Genie I/II assay in GB and GC. HIV positivity was detected in 44 of 46 samples by all screening and confirmatory assays. A diagnostic strategy based on Inno-LIA and HIV-1/2 RNA detection assays allowed accurate discrimination between HIV-1 and HIV-2 in 84% of single infections and confirmed 32% of double infections. In samples with double reactivity in the Inno-LIA test and no detection of both genomes, cross-reactivity likely hampered the identification of true double infections. In conclusion, the implementation of a diagnostic strategy, based on multiple specific serological tests and highly sensitive quantitative PCR assays, is recommended to ensure accurate HIV-2 diagnosis and appropriate therapy for individuals from areas in which the virus is endemic.
Subject(s)
HIV Antibodies/blood , HIV Infections/diagnosis , HIV-2/isolation & purification , RNA, Viral/isolation & purification , Adolescent , Adult , Female , Guinea-Bissau , HIV Infections/virology , HIV-1/classification , HIV-1/genetics , HIV-1/immunology , HIV-1/isolation & purification , HIV-2/classification , HIV-2/genetics , HIV-2/immunology , Humans , Immunoassay/methods , Male , Middle Aged , Molecular Sequence Data , Nucleic Acid Amplification Techniques/methods , RNA, Viral/genetics , Sensitivity and Specificity , Sequence Analysis, DNA , Young AdultABSTRACT
BACKGROUND: Antiretroviral treatment programs in sub-Saharan Africa have high rates of early mortality and loss to follow-up. Switching to second-line regimens is often delayed because of limited access to laboratory monitoring. METHODS: Retrospective analysis was performed of a cohort of adults who initiated a standard first-line antiretroviral treatment at 5 public sector sites in 3 African countries. Monitoring included routine CD4 cell counts, human immunodeficiency virus RNA measures, and records of whether appointments were kept. Incidence and predictors of death, loss to follow-up, and switch to second-line regimens were analyzed by time-to-event approaches. RESULTS: A total of 3749 patients were analyzed; at baseline, 37.1% were classified as having World Health Organization disease stage 3 or 4, and the median CD4 cell count was 192 cells/mL. First-line regimens were nevirapine based in 96.5% of patients; 17.7% of patients attended <95% of their drug pickup appointments. During 4545 person-years of follow-up, mortality was 8.6 deaths per 100 person-years and was predicted by lower baseline CD4 cell count, lower hemoglobin level, and lower body mass index (calculated as weight in kilograms divided by the square of height in meters); more-advanced clinical stage of infection; male sex; and more missed drug pickup appointments. Dropouts (which accrued at a rate of 2.1 dropouts per 100 person-years) were predicted by a lower body mass index, more missed visits and missed drug pickup appointments, and later calendar year. Incidence of switches to second-line regimens was 4.9 per 100 person-years; increased hazards were observed with lower CD4 cell count and earlier calendar year at baseline. In patients who switched, virological failure was predicted by combined clinical and CD4 criteria with 74% sensitivity and 30% specificity. CONCLUSIONS: In an antiretroviral treatment program employing comprehensive monitoring, the probability of switching to second-line therapy was limited. Regular pickup of medication was a predictor of survival and was also strongly predictive of patient retention.
Subject(s)
Anti-Retroviral Agents/administration & dosage , HIV Infections/drug therapy , HIV Infections/mortality , HIV-1 , Adult , Africa South of the Sahara/epidemiology , CD4 Lymphocyte Count , Cohort Studies , Drug Administration Schedule , Female , Humans , Male , Patient Dropouts , Retrospective StudiesABSTRACT
BACKGROUND: Maintaining treatment adherence among the growing number of patients receiving antiretroviral treatment in Africa is a dramatic challenge. The objective of our study was to explore the results of a computerized pill count method and to test the validity, sensitivity, and specificity of this method with respect to viral load measurement in an African setting. METHODS: We performed a prospective, observational study involving patients who received first-line highly active antiretroviral therapy in Mozambique from 1 April 2005 through 31 March 2006. Enrolled patients had received treatment for at least 3 months before the study. For defining treatment adherence levels, pill counts were used, and the results were analyzed with viral load measurements at the end of the observation period. RESULTS: The study involved 531 participants. During the 12 months of observation, 137 patients left the program or discontinued first-line therapy. Of the remaining 394 patients, 284 (72.1%) had >95% treatment adherence; of those 284 patients, 274 (96.5%) had a final viral load <1000 copies/mL. A Cox proportional hazards analysis revealed that the relationship between >95% treatment adherence and the final viral load was closer than that between >90% treatment adherence and viral load. CONCLUSIONS: Treatment adherence >95% maximizes the results of the nonnucleoside reverse-transcriptase inhibitor-based regimen. The pill count method appears to be a reliable and economic tool for monitoring treatment adherence in resource-limited settings.
