Genotype and antiretroviral drug resistance of human immunodeficiency virus-1 in Saudi Arabia

OBJECTIVE: To analyze antiretroviral drug resistance and determine the genotype of human immunodeficiency virus (HIV)-1 in Saudi patients by sequencing an amplified region of the viral pol gene.

METHODS: This retrospective study analyzed data from plasma samples submitted for genotypic drug sensitivity monitoring. Samples were analyzed at the Special Infectious Agent Unit, King Fahd Medical Research Center of King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia from August 2004 to June 2009. The Viroseq2.5 kit (Celera/Abbott) was used with ABI Prism 3100 sequencer. All patients were Saudi nationals and were on antiretroviral therapy, some experiencing treatment failure.

RESULTS: Based on protease region (PR), genotypes of 63 samples were as follows: C:22, G:21, B:9, CRF02_AG:5, D:3, A:1, F:1, and J:1. Based on reverse transcriptase region (RT), genotypes were as follows: C:23, G:24, B:9, CRF02_AG: 2, D:2, A:1, and F:1. Antiretroviral susceptibility testing results were as follows: 52% of the isolates were susceptible to all 3 major classes of antiretroviral drugs used, 41% had mutations known to confer high level resistance to one or more of the nucleoside analogue reverse transcriptase inhibitors, 16% had mutations known to confer high level resistance to non-nucleoside analogues reverse transcriptase inhibitors, 13% had mutations known to confer high level resistance to one or more of the protease inhibitors (PI). Most isolates were susceptible to 2 or at least one class of antiretroviral, and only 3% of the isolates had resistance to several members of all 3 classes.

CONCLUSION: Antiretroviral resistance is not uncommon in Saudi patients on antiretroviral therapy.