Browsing by Author "Serwadda, D."

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    Hepatitis B incidence and prevention with antiretroviral therapy among HIV positive individuals in Rakai, Uganda
    (AIDS (London, England), 2017) Seremba, E.; Ssempijja, V.; Kalibbala, S.; Gray, R. H.; Wawer, M. J.; Nalugoda, F.; Casper, C.; Phipps, W.; Ocama, P.; Serwadda, D.; Thomas, D. L.; Reynolds, S. J.
    Antiretroviral therapy (ART) may interfere with replication of hepatitis B (HBV) raising the hypothesis that HBV infection might be prevented by ART. We investigated the incidence and risk factors associated with HBV among HIV-infected adults in Rakai, Uganda. Methods—We screened stored sera from 944 HIV-infected adults enrolled in the Rakai Community Cohort Study between September 2003 and March 2015 for evidence of HBV exposure. Serum from participants who tested anti-HBc negative (497) at baseline were tested over 3-7 consecutive survey rounds for incident HBV. Poisson incidence methods were used to estimate incidence of HBV with 95% confidence intervals while Cox proportional regression methods were used to estimate hazard ratios.
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    Immune correlates of HIV exposure without infection in foreskins of men from Rakai, Uganda
    (Mucosal immunology, 2014) Prodger, J. L.; Hirbod, T.; Kigozi, G.; Nalugoda, F.; Reynolds, S. J.; Galiwango, R.; Shahabi, K.; Serwadda, D.; Wawer, M.J.; Gray, R. H.; Kaul, R.
    Human immunodeficiency virus (HIV) susceptibility is heterogenous, with some HIV-exposed but seronegative (HESN) individuals remaining uninfected despite repeated exposure. Previous studies in the cervix have shown that reduced HIV susceptibility may be mediated by immune alterations in the genital mucosa. However, immune correlates of HIV exposure without infection have not been investigated in the foreskin. We collected sub-preputial swabs and foreskin tissue from HESN (n¼20) and unexposed control (n¼57) men undergoing elective circumcision. Blinded investigators assayed swabs for HIV-neutralizing IgA, innate antimicrobial peptides, and cytokine levels. Functional T-cell subsets from foreskin tissue were assessed by flow cytometry. HESN foreskins had elevated a-defensins (3,027 vs. 1,795 pgml 1,P¼0.011) and HIV-neutralizing IgA(50.0 vs. 13.5%ofmen,P¼0.019).Foreskin tissue from HESN men contained a higherdensityofCD3 T cells (151.9 vs. 69.9 cellsmm 2, P¼0.018), but a lower proportion of these was Th17 cells (6.12 vs. 8.04%of CD4 Tcells, P¼0.007), and fewer produced tumor necrosis factor a (TNFa) (34.3 vs. 41.8% of CD4 Tcells, P¼0.037; 36.9 vs. 45.7%of CD8 T cells, P¼0.004). A decrease in the relative abundance of susceptible CD4 T cells and local TNFa production, in combination with HIV-neutralizing IgA and a defensins, may represent a protective immune milieu at a site of HIV exposure.
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    The validity of self-reported antiretroviral use in persons living with HIV: a population-based study
    (AIDS, 2018) Grabowski, M.K.; Reynolds, S.J.; Kagaayi, J.; Gray, R.H.; Clarke, W.; Chang, L.C.; Nakigozi, G.; Laeyendecker, O.; Redd, A.D.; Goud-Billoux, V.; Ssekubugu, R.; Nalugoda, F.; Wawer, M.J.; Serwadda, D.; Quinn, T.C.; Tobian, A.A.R.
    To assess the validity of self-reported antiretroviral therapy use (ART) using population-based cohort data. Methods—Self-reported ART use and non-use was compared to a validated laboratory assay in 557 HIV-positive participants in the Rakai Community Cohort Study surveyed between September and December 2011 in Rakai, Uganda. The study population included participants from seven communities, including one fishing community with high HIV prevalence (~41%). ART use was assayed using liquid chromatography-tandem mass spectrometry which detects 20 antiretroviral (ARV) drugs. HIV viral load measurements were also obtained. Individuals with ≥2 antiretroviral (ARV) drugs detected were considered to be using ART. Results—153 (27%) participants self-reported ART use of whom 148 (97%) had ≥2 ARV drugs detected. There were ≥2 ARV drugs detected in 11% (n=44/404) of individuals with no self-reported ART use. Overall, the specificity of self-reported ART use was 99% (95%CI:97–100%) and the sensitivity was 77% (70–83%). Positive and negative predictive values were 97% (95%CI: 93–99%) and 89% (95%CI: 86–92%), respectively. Non-disclosure of ART use was significantly more common in younger persons (<30 years) and among those in trading occupations, but did not vary by community of residence. Conclusions—Self-reported ART use has high specificity and moderate sensitivity providing reasonable, but conservative estimates of population-based ART use. There is more under- reporting of ART use among younger persons and traders suggesting a need for more research on barriers to self-reporting of ART use in these sub-groups.