Surveillance of transmitted drug resistance in untreated HIV‐infected patients in Cuba

Abstract

BackgroundKnowledge of transmitted drug resistance (TDR) in untreated HIV‐infected patients is fundamental in the epidemiological surveillance programs, because it is associated with suboptimal virological outcome of first‐line HAART. The aim of this study was to evaluate the epidemiology of TDR in newly diagnosed Cuban patients.Methods250 HIV‐1‐infected patients diagnosed between 2009 and 2011 were included in the study. RNA was isolated from plasma and used as target to amplify the pol gen by RT‐nested PCR. PCR products were sequenced and the data generated used to determine the viral subtype by phylogenetic analyses. The TDR were detected by means of Stanford University calibrated population resistance tool, using the 2009 surveillance drug resistance mutations list.ResultsBaseline characteristic were as follows: 78.4% of the cases were males, mean age was 35.5 years, 66.3% of infections were acquired by homosexual transmission and the median viral load was 4.6 log. The 39.2% of the analyzed samples corresponded to the subtype B and 60.8% for non‐B genetic forms, with prevalence of CRF 19_cpx, CRF 20 BG and CRF 23 BG [1]. The overall prevalence of TDR increased in comparison with previous studies (19.2% versus 5.2%) [2]. The majority of mutations were seen within the group of nucleoside reverse transcriptase (NRTI) (8.5%) and non‐NRTI (9.7%). TDR was less common in the group of protease inhibitors (1.7%). The most common mutations were M184V and K103N for the NRTIs and NNRTIs, respectively. The prevalence of TDR in samples of the subtype G was significant (p = 0.005) in comparison with other genetic forms.ConclusionsThis study confirms an increase in the transmission of resistance‐associated mutations, which indicates the importance of maintaining a constant epidemiological surveillance of the TDR in newly diagnosed Cuban patients.