Resistance to antiretrovirals in HIV-infected pregnant women.
BACKGROUND
Antiretrovirals suppress HIV replication and prevent mother-to-child-transmission of HIV (PMTCT). Resistance to antiretrovirals may reduce the efficacy of PMTCT and/or complicate treatment of maternal or infant infection.


OBJECTIVE
To assess resistance to antiretrovirals during pregnancy.


METHODS
Retrospective chart review of 44 pregnancies.


RESULTS
Twenty-two patients were antiretroviral treatment-naïve, 8 were on therapy, and 14 had prior therapy, but were off medication when the genotyping was performed. Major mutations were found in 10 antiretroviral-experienced women, including 5 women with major mutations to 2 classes of drugs (none to 3 classes). Major mutations were most common for lamivudine, nevirapine, zidovudine, stavudine, and abacavir. Three women had significant resistance to zidovudine/lamivudine, a combination recommended in PMTCT guidelines. Despite significant antiretroviral resistance, 6 of 8 women with plasma HIV RNA measured within 4 weeks of delivery achieved <50 copies/mL. All neonates were uninfected. Among 6 women who received antiretrovirals exclusively for PMTCT, there were no remarkable changes of the HIV genotype before and after pregnancy.


CONCLUSIONS
Resistance to antiretrovirals was common in antiretroviral-experienced pregnant women, but not in naïve women. The 14% prevalence of resistance to zidovudine and lamivudine in antiretroviral-experienced women suggests that alternative NRTI are desirable for this group of patients.
Weinberg
Adriana
A
University of Colorado Denver School of Medicine, Aurora, CO 80045, USA. Adriana.Weinberg@ucdenver.edu
Forster-Harwood
Jeri
J
McFarland
Elizabeth J
EJ
Pappas
Jennifer
J
Davies
Jill K
JK
Kinzie
Kay
K
Barr
Emily A
EA
Paul
Suzanne M
SM
Salbenblatt
Carol R
CR
Soda
Elizabeth
E
Vazquez
Anna
A
Levin
Myron J
MJ