Nucleoside exposure in the children of HIV-infected women receiving antiretroviral drugs: Absence of clear evidence for mitochondrial disease in children who died before 5 years of age in five United States cohorts

Background: Nucleoside reverse transcriptase inhibitors (NRTIs) have been associated with mitochondrial toxicity in individuals receiving treatment. A report of two deaths in Europe attributed to mitochondrial dysfunction in HIV-uninfected infants with perinatal NRTI exposure prompted a review of five U.S. cohorts. Methods: Deaths in HIV-exposed children <60 months of age and HIV-uninfected or indeterminate were reviewed. Review included birth history; perinatal antiretroviral drug exposure; hospital, laboratory, and clinic records; death reports; autopsy results; and local physician queries. Deaths were classified as unrelated (Class 1), unlikely related (Class 2), possibly related (Class 3), or highly suggestive or proven relationship (Class 4), to mitochondrial dysfunction; sudden infant death syndrome (SIDS) was categorized separately. Results and Conclusions: Among over 20,000 children of HIV-infected women, over half of whom had been exposed to NRTIs, 223 died. In HIV-uninfected children, 26 deaths were attributed to Class 1, and 4 were attributed to SIDS. In HIV-indeterminate children, 141, 10, 3, and 0 were Classes 1, 2, 3, and 4, respectively; 33 were due to SIDS and 6 could not be classified. There was no indication that antiretroviral exposure was associated with Class 2 or 3 deaths, or deaths from SIDS. A search for mitochondrial dysfunction among living children in these cohorts is ongoing.