Drug resistance in HIV patients with virological failure or slow virological response to antiretroviral therapy in

Background: The ongoing scale-up of antiretroviral therapy (ART) in sub-Saharan Africa has prompted the interest in surveillance of transmitted and acquired HIV drug resistance. Resistance data on virological failure and mutations in HIV infected populations initiating treatment in sub-Saharan Africa is sparse. Methods: HIV viral load (VL) and resistance mutations pre-ART and after 6 months were determined in a prospective cohort study of ART-naïve HIV patients initiating first-line therapy in Jimma, Ethiopia. VL measurements were done at baseline and after 3 and 6 months. Genotypic HIV drug resistance (HIVDR) was performed on patients exhibiting virological failure (>1000 copies/mL at 6 months) or slow virological response (>5000 copies/mL at 3 months and <1000 copies/mL at 6 months). Results: Two hundred sixty five patients had VL data available at baseline and at 6 months. Virological failure was observed among 14 (5.3%) participants out of 265 patients. Twelve samples were genotyped and six had HIV drug resistance (HIVDR) mutations at baseline. Among virological failures, 9/11 (81.8%) harbored one or more HIVDR mutations at 6 months. The most frequent mutations were K103N and M184VI. Conclusions: Our data confirm that the currently recommended first-line ART regimen is efficient in the vast majority of individuals initiating therapy in Jimma, Ethiopia eight years after the introduction of ART. However, the documented occurrence of transmitted resistance and accumulation of acquired HIVDR mutations among failing patients justify increased vigilance by improving the availability and systematic use of VL testing to monitor ART response, and underlines the need for rapid, inexpensive tests to identify the most common drug resistance mutations. Background In Ethiopia approximately 1.3 million people live with HIV and the estimated adult HIV prevalence is 1.5% [1]. During the past eight years, there has been a rapid scale-up of antiretroviral therapy (ART) which reached 250,000 adults in 2012, representing 86% of eligible patients [2,3]. As ART roll-out continues in resource-limited settings, the risk of potential emergence of HIV drug resistance (HIVDR) is growing. This could be due to the absence of virological monitoring in routine clinical care and the use of drugs with low genetic barriers such as non-nucleoside reverse transcriptase inhibitors [NNRTI] [4]. The use of nevirapine as monotherapy for preventing mother-tochild transmission may have further contributed to the problem [5]. Viral replication under suboptimal antiretroviral pressure leads to accumulation of resistance mutations, which limit future therapeutic choices [6] as mutations conferring resistance to one drug frequently confer cross resistance to other antiretroviral drugs within the same class [7]. Thus, it is essential for patient management to define the pattern of both primary and secondary resistance mutations. The World Health Organization (WHO) recommends surveillance for transmitted HIVDR among antiretroviral* Correspondence: alemseged.abdisssa@ju.edu. et Department of Medical Laboratory Sciences & Pathology, Jimma University, Jimma, Ethiopia Department of Infectious Diseases, Odense University Hospital, Odense, Denmark Full list of author information is available at the end of the article © 2014 Abdissa et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Abdissa et al. BMC Infectious Diseases 2014, 14:181 http://www.biomedcentral. com/1471-2334/14/181