Study of antiretroviral mutants in HIV patients with treatment failures and the effect of risk factors in the virological failures

Abstract

The most important factor related to treatment response in this study was adherence to treatment. Mutations in RT were related to the treatment failure while the ones found in PT were secondary mutations which have been previously described to influence the selection of primary resistance mutations in these regions. The study reveals the urgency to detect resistant mutations in VF to be considered by physicians for selection of treatment schedule, to analyze basal HIV patients for monitoring of the spread of resistant mutations and the importance to reinforce the adherence in the patients for overall treatment outcome.

Variability in HIV-1 partial genomic sequences in Costa Rican patients: analysis with different bioinformatics tools

“…Costa Rica has been able to provide better support for HIV patients undergoing treatment with a follow-up that showed a level of only 10% VF in the overall population treated. In an earlier study, we showed that all BS from patients who responded well to antiviral treatment had a viral load of < 10 4 copies/mL (12). In spite of that, we found a high viral variability in the VF patients, with low treatment adherence (Table 2).…”

“…In spite of that, we found a high viral variability in the VF patients, with low treatment adherence (Table 2). This variable, together with resistant mutants, was associated with VF in this early study (12). Variables such as sex, age, place of residence, risk group, occupation, and whether the persons were infected outside of Costa Rica were not found to correlate with HIV-1 intraor intersubtype.…”

“…A blood sample was collected from each patient (VF and BS) and the plasma was referred to the International Center of Medical Research and Training and kept frozen below -40 °C until analyzed. All 113 samples (VF and BS) were sequenced with a TruGene HIV-1 genotyping kit (Visible Genetics, Toronto, Ontario, Canada) to detect resistant mu-tants of HIV RT and protease (PR) (12). Additionally, 22 samples from the VF patients were sequenced in the env region V3 loop.…”

“…However, this procedure is very costly and time-consuming (8,9). Partial genomic sequencing with commercial kits allows us to determine resistant mutants of HIV (10)(11)(12) and provides an opportunity to analyze sequenced materials in order to study HIV variability and the possibility of detecting recombinants in different geographic areas using several software packages. Sequence analysis of env and pol together is a frequent choice for determining viral heterogeneity (13)(14)(15)(16).…”

“…In Costa Rica and other Central American countries, there are no reports describing the distribution of HIV-1 subtypes or recombinant forms. In a study with patients receiving treatment at Costa Rica's Social Security System (Caja Costarricense de Seguro Social, CCSS) where more than 90% of Costa Rica's HIV patients needing treatment receive it, it was determined that virologic failure (VF) in ART was due to HIV-resistant mutants, and the appearance of these mutants was related to lack of adherence to ART or high viral load at the initiation of treatment (12).…”