Prevalence of drug resistance and importance of viral load measurements in Honduran HIV‐infected patients failing antiretroviral treatment

Abstract

ObjectiveThe Honduran HIV/AIDS Program began to scale up access to HIV therapy in 2002. Up to May 2008, more than 6000 patients received combination antiretroviral therapy (cART). As HIV drug resistance is the major obstacle for effective treatment, the purpose of this study was to assess the prevalence of antiretroviral drug resistance in Honduran HIV-1-infected individuals. MethodsWe collected samples from 138 individuals (97 adults and 41 children) on cART with virological, immunological or clinical signs of treatment failure. HIV-1 pol sequences were obtained using an in-house method. Resistance mutations were identified according to the 2007 International AIDS Society (IAS)-USA list and predicted susceptibility to cART was scored using the ANRS algorithm. ResultsResistance mutations were detected in 112 patients (81%), 74% in adults and 98% in children. Triple-, dual-and single-class drug resistance was documented in 27%, 43% and 11% of the study subjects, respectively. Multiple logistic regression showed that resistance was independently associated with type of treatment failure [virological failure (odds ratio (OR) 5 1) vs. immunological failure (OR 5 0.11; 95% confidence interval (CI) 0.030-0.43) vs. clinical failure (OR 5 0.037; 95% CI 0.0063-0.22)], route of transmission (OR 5 42.8;, and years on therapy (OR 5 1.81; 95% CI 1.11-2.93). ConclusionThe prevalence of antiretroviral resistance was high in Honduran HIV-infected patients with signs of treatment failure. A majority of study subjects showed dual-or triple-class resistance to nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors and protease inhibitors. Virologically defined treatment failure was a strong predictor of resistance, indicating that viral load testing is needed to correctly identify patients with treatment failure attributable to resistance.Keywords: antiretroviral treatment, drug resistance, HIV, mutations, treatment failure IntroductionThe mortality of HIV-1 infection has decreased dramatically in the developed parts of the world following the introduction of combination antiretroviral therapy (cART) in 1996 [1][2][3]. cART typically involves therapy with two Honduras is estimated to have one of the highest HIV-1 prevalences (0.7%; range 0.4-1.4%) in Latin America [6].Of the large number of HIV-positive individuals, 12 000 are estimated to be in need of cART (Table 1). The National HIV/AIDS Program in Honduras began to scale up access to therapy in 2002, and since then many patients have gained access to cART. At present approximately 6000 patients have been under treatment, of whom around 700 have interrupted therapy and more than 800 have died [7].The goal of modern cART is to suppress viral replication and maintain plasma HIV-1 RNA levels in treated patients below the detection limit of sensitive assays (i.e. o50 HIV-1 RNA copies/mL plasma) [3,4]. Treatment failure during cART is a significant clinical problem. Poor adherence is the most common cause of treatment failure, but failure can al...

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Short Communication: Prevalence of HIV Type 1 Transmitted Drug Resistance in Slovenia: 2005–2010

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