Prevalence of HLA-B*5701 and Its Relationship with Abacavir Hypersensitivity Reaction in Iranian HIV-Infected Patients

BACKGROUND Hypersensitivity reaction (HSR) is a major adverse effect of abacavir (ABC), which occurs in 5-8% of Caucasians. The relationship between Human Leukocyte Antigen (HLA) and ABC HSR has been reported in various populations. It has been proposed to administer ABC only to HLA-B*5701 negative patients to avoid this reaction. The purpose of this study was to assess the prevalence of HLA-B*5701 in Iranian HIV positive patients. We also sought to find the relationship between this allele with ABC HSR in patients who received the medication. MATERIALS AND METHODS We screened patients for HLA-B*5701 allele using SybrGreen real time PCR-melting method on blood samples from HIV positive patients who were referred to our hospital. The quality of the extracted genome was evaluated by B-globin housekeeping gene as internal control prior to HLA-B*5701 allele screening. RESULTS Of 198 HIV-infected patients, 6 (3.0%) had the HLA-B*5701 allele (95% CI, 1%-5%). Among the 28 patients who were given ABC, one individual had the HLA-B*5701 allele and experienced ABC HSR. CONCLUSION Prevalence of HLA-B*5701 in Iranian patients was lower than that in Caucasians but was comparable with that of other Middle Eastern populations. Screening for HLA-B*5701 before ABC administration as part of antiretroviral therapy may reduce the risk of HSR.