impact of vitamin supplements on haart related hematological abnormalities in hiv-infected patients

background: the human immunodeficiency virus (hiv) is one of the most life- threatening human infections. the advent of highly active antiretroviral therapy (haart) has dramatically changed the course of hiv infection and patients' quality of life. in addition to the benefits, haart can have numerous side effects and toxicities. therefore, we aimed to assess the impact of short-term vitamins treatment on hematological parameters of hiv infected patients receiving haart.   methods: this cross-sectional study was conducted on 100 confirmed hiv positive patients who referred to shiraz hiv/aids research center in southwest of iran. the first-line of haart regimen contained zidovudine, lamivudine, and efavirenz. the studied population received vitamin b12 weekly and folic acid daily for at least one month.   results: after receiving haart for at least 6 months with adherence above 90%, significant differences (p< 0.05) were observed in mcv, mch, hct, tlc and rbc status compared to the baseline parameters. after one month of treatment, vitamins in four hematological parameters including tlc, mcv, rbc, and wbc showed significant differences compared to haart parameters.   conclusion: combined administration of b12 and folate supplements is a beneficial adjuster on hematologic status of hiv infected persons receiving haart. however, future research with larger studied population and longer follow-up periods is required. moreover, especial attention should be given to gender because the effect of vitamins was significantly different on some hematologic parameters between different genders.