HIV antiretroviral resistance and transmission in mother-infant pairs enrolled in a large perinatal study

Abstract

Background

The presence of antiretroviral drug resistant mutations (DRMs) may be particularly problematic in HIV-infected pregnant women as it can lead to mother to child transmission (MTCT) of resistant HIV strains. This study evaluated the prevalence and the effect of antiretroviral DRMs in previously untreated mother-infant pairs.

Methods

A case-control design of 1:4 (1 transmitter to 4 non-transmitters) was utilized to evaluate DRMs as a predictor of HIV MTCT in specimens obtained from mother-infant pairs. ViroSeq HIV-1 Genotyping testing was performed on mother-infant specimens to assess for clinically relevant DRMs.

Results

One hundred and forty infants acquired HIV-infection; of these 123 mother-infant pairs (88%) had specimens successfully amplified using ViroSeq and assessed for drug resistance genotyping. Additionally, 483 (86%) of 560 women who did not transmit HIV to infants also had samples evaluated for DRMs. Sixty-three (10%) of 606 women had clinically relevant DRMs; 12 (2%) had DRMs against >1 drug class. Among 123 HIV-infected infants, 13 (11%) had clinically relevant DRMs, with 3 (2%) harboring DRMs against >1 drug class. In univariate and multivariate analyses, DRMs in mothers were not associated with increased HIV MTCT (AOR 0.8, 95% CI 0.4-1.5). Presence of DRMs in transmitting mothers was strongly associated with DRM presence in their infants (p<0.001).

Conclusion

Pre-existing DRMs were common in untreated HIV infected pregnant women, but did not increase the risk of HIV MTCT. However, if women with DRMs are not virologically suppressed, they may transmit resistant mutations, thus complicating infant management.

Clinical Trials Registration Number

NCT00099359