Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 46 9 2017 09 03 1256 1264 Molood FARROKHI Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran Samaneh MOALLEMI Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran Reza SHIRKOOHI Group of Genetics, Cancer Research Center, Cancer Institute of Iran, Tehran University of Medical Sciences, Tehran, Iran Reza GOLMOHAMMADI Dep. of Microbiology, Golestan University of Medical Sciences, Gorgan, Iran Sara AHSANI-NASAB Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran Sara SARDASHTI Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran Ladan ABBASIAN Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran Kazem BAESI Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, Iran Minoo MOHRAZ Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran 2017 09 03 2017 09 03 Background: This study aimed to determine drug resistance mutations in patients with virological failure and find correlation between HIV drug resistance test and viral load. Methods: Blood sample was collected from 51 patients who suspicious treatment failure in the center of Imam Khomeini Hospital, Tehran, Iran in 2015. Viral voluntary counseling and testing load test was done and the patients with viral load above 1000 copies choose for detection of drug resistance mutations by genotyping method (29 patients). Results: The majority of patients (82.75) harbored the HIV subtype CRF 35 A-D. The 86.2% patients compromised at least one resistance mutation. The analysis of reverse transcriptase showed M184V (68.9%), T215YISF (44.8%), K103N (27.6%) and the analysis results of protease revealed G73SC (13.8%) and I47VA (6.9%). Eventually, the significant correlation between viral load and drug resistance was found. Conclusion: The result of our research stress the significance of recognizing drug resistant on time that prohibits the accumulation of drug resistance mutation and circulates the resistance strain of HIV-1 virus and the importance of national study according to the reliable findings for treatment guidelines.   https://ijph.tums.ac.ir/index.php/ijph/article/view/10999 https://ijph.tums.ac.ir/index.php/ijph/article/download/10999/5685