Detection of HIV drug resistance mutations in pregnant women receiving single dose Nevirapine in south India

Single dose of Nevirapine to prevent mother to child transmission of HIV is the commonest preventive regimen in resource-limited countries. The objective of this study was to detect drug-resistant virus after single dose of Nevirapine (sdNVP) provided to delivering HIV seropositive (HIV+ve) women and to evaluate the time taken for its decay. Of the 36 consenting HIV+ve pregnant women enrolled into the study, the mean hemoglobin and total lymphocyte counts were 10.8 g/dl and 1843 cells/mm 3 , respectively. Mean CD4 counts in 64% of women was 363 cells/mm 3 and mean viral load for 16/36 women was 28,143 copies/ml of plasma. Nevirapine-resistance mutations were detected in 28% of women at delivery; using OLA (Oligonucleotide Ligation Assay). K103N mutations were seen in 19.4% of women while the Y181C mutation was seen in 5%. Both the mutations were detected in 2.7% of women. Sequential blood samples collected at delivery, 7-10 days, 6 weeks, 4 months, 6 months and one year postpartum showed that 81% of K103N mutations and 66.7% of Y181C mutations were detected at 6 weeks postpartum . Wild-type virus had replaced the mutants by one year postpartum in all women except one. These observations are relevant for future treatment with antiretroviral therapy in these women for their HIV disease.