Browsing by Author "Katusiime, Mary Grace"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    HIV-1 RNA testing of pooled dried blood spots is feasible to diagnose acute HIV infection in resource limited settings
    (Medpharm Publications, 2018) Dowling, Wentzel; Veldsman, Kirsten; Katusiime, Mary Grace; Maritz, Jean; Bock, Peter; Meehan, Sue-Ann; Schalkwyk, Marije Van; Cotton, Mark F.; Preiser, Wolfgang; Van Zyl, Gert U.
    Objectives: Rapid human immunodeficiency virus (HIV) antibody tests, routinely used for diagnosis in adults and older children in resource-limited settings (RLS), do not detect early HIV infections prior to seroconversion or when antibody levels are still low. Nucleic acid amplification to detect HIV-1 RNA is the most sensitive method for acute HIV infection diagnosis, but is costly. We therefore investigated HIV- 1 RNA testing of pooled dried blood spots (DBS) to diagnose acute HIV infection. Design: Laboratory-based investigation. Methods: DBS were collected from HIV-1 Voluntary Counselling and Testing (HVCT) clients who tested negative on the Advanced QualityTM HIV antibody rapid test. DBS samples from five participants were pooled and tested on the COBAS AmpliPrep/COBAS TaqMan HIV-1 (CAP/CTM) Test v2. Individual DBS were tested when pools tested positive (> 200 RNA copies/ml). Acute infection was confirmed by HIV viral load testing, two fourth-generation HIV serological assays, and Geenius™ HIV 1/2 Assay for antibody band identification. Results: Of 482 participants who were tested, one (0.2%) had acute HIV infection: Fourth generation serology was low-level positive, the plasma HIV viral load was 15 929 HIV-1 RNA copies/ml, gp160 and gp41 antibody bands were positive and the p31 band was negative, indicating a Fiebig Stage 5 infection. Conclusions: Pooled DBS HIV-1 RNA testing is efficient compared to individual testing for acute HIV infection diagnosis. Early identification of participants with acute HIV infection facilitates immediate initiation of antiretroviral therapy to improve immune recovery and prevent transmission to others.
  • Thumbnail Image
    Item
    No evidence of HIV replication in children on antiretroviral therapy
    (American Society for Clinical Investigation, 2017-04) Van Zyl, Gert U.; Katusiime, Mary Grace; Wiegand, Ann; McManus, William R.; Bale, Michael J.; Halvas, Elias K.; Luke, Brian; Boltz, Valerie F.; Spindler, Jonathan; Laughton, Barbara; Engelbrecht, Susan; Coffin, John M.; Cotton, Mark F.; Shao, Wei; Mellors, John W.; Kearney, Mary F.
    ENGLISH ABSTRACT: It remains controversial whether current antiretroviral therapy (ART) fully suppresses the cycles of HIV replication and viral evolution in vivo. If replication persists in sanctuary sites such as the lymph nodes, a high priority should be placed on improving ART regimes to target these sites. To investigate the question of ongoing viral replication on current ART regimens, we analyzed HIV populations in longitudinal samples from 10 HIV-1–infected children who initiated ART when viral diversity was low. Eight children started ART at less than ten months of age and showed suppression of plasma viremia for seven to nine years. Two children had uncontrolled viremia for fifteen and thirty months, respectively, before viremia suppression, and served as positive controls for HIV replication and evolution. These latter 2 children showed clear evidence of virus evolution, whereas multiple methods of analysis bore no evidence of virus evolution in any of the 8 children with viremia suppression on ART. Phylogenetic trees simulated with the recently reported evolutionary rate of HIV-1 on ART of 6 × 10⁻⁴ substitutions/site/month bore no resemblance to the observed data. Taken together, these data refute the concept that ongoing HIV replication is common with ART and is the major barrier to curing HIV-1 infection.