Title: CD4+ T-cell count may not be a useful strategy to monitor antiretroviral therapy response in HTLV-1/HIV co-infected patients
Authors: Vandormael A, Rego F, Danaviah S, Alcantara L, Boulware D, de Oliveira T.
Journal: Current HIV Research,:doi: 10.2174/1570162X15666170216114917 (2017)
BACKGROUND: HTLV-1/HIV co-infection is known to elevate the CD4+ T-cell counts of treatment-naive persons. We investigated whether HTLV-1/HIV co-infected patients continued to have elevated CD4+ T-cell counts after developing virologic failure on antiretroviral therapy (ART).
METHODS: The data comes from a drug resistance study located in the KwaZulu-Natal province of South Africa. All participants (N=383) presented for repeated CD4+ T-cell count and HIV viral load level testing between January 2006 and March 2014. We used a random-coefficient model to estimate the change in CD4+ T-cell count and HIV viral load level by HTLV-1/HIV co-infection status over time, adjusting for age, sex, and duration of virologic failure.
RESULTS: HTLV-1/HIV co-infected participants (n=8) had higher CD4+ T-cell counts, with a positive difference of 117.2 cells/uL at the ART initiation date (p-value=0.001), 114.7 cells/uL (p-value<0.001) 12 months after this date, and 112.3 cells/uL (p-value=0.005) 24 months after this date, holding all else constant. In contrast, there was no difference in the HIV viral load level by HTLV-1/HIV co-infected status throughout the observation period.
CONCLUSIONS: We show that HTLV-1/HIV co-infected participants continued to have elevated CD4+ T-cell counts after developing virologic failure on ART, despite no difference in their HIV viral load levels when compared with HIV mono-infected participants. Our results indicate that CD4+ T-cell count testing may not be a useful strategy to monitor ART response in the presence of HTLV-1 infection.