New evidence shows that drug-resistant virus passed from mother to child can quickly establish itself in infants' CD4 cells, where it can hide for years, likely limiting their options for future treatment, according to a study published in the May 15 issue of The Journal of Infectious Diseases.
The study, conducted by Deborah Persaud, MD, of Johns Hopkins University School of Medicine with colleagues working throughout the United States, analyzed HIV-infected infants less than six months of age enrolled in a multicenter clinical trial covering 10 states. Their results showed that five of 21 HIV-positive infants were infected with drug-resistant HIV transmitted from their mothers'a surprisingly high figure. Of those five, four were resistant to nonnucleoside reverse transcriptase inhibitors, which are commonly used to prevent mother-to-child transmission. All had uncommon drug-resistance mutations that some resistance tests would miss.
Researchers found these resistant viruses quickly took up residence in inactive CD4 cells, from which they could later launch an attack that NNRTIs could not stop. The news was not all bad, though, since protease inhibitors were effective in controlling viral load and NNRTI-resistant virus strains for all infants studied.