Abstract:
Early diagnosis of HIV infection among infants and children is critical as
prompt initiation of antiretroviral therapy prevents morbidity and death. Yet
despite advances in the accuracy and availability of infant HIV diagnostic
testing, there are increasing challenges with making an early definitive
diagnosis. These challenges relate primarily to advances in prevention of
mother-to-child transmission (PMTCT) of HIV. Although PMTCT programs
have proven to be highly effective in reducing infant HIV infection, infants
who are HIV-infected may achieve virological suppression and loss of
detectability of HIV nucleic acid prior to diagnosis because of antiretroviral
drug exposure. Hence, false-negative and indeterminate HIV polymerase
chain reaction (PCR) results can occur, especially among high-risk infants
given multi-drug prophylactic regimens. However, the infant HIV diagnostic
landscape is also complicated by the inevitable decline in the positive
predictive value of early infant diagnosis (EID) assays. As PMTCT
programs successfully reduce the mother-to-child transmission rate, the
proportion of false-positive EID results will increase. Consequently,
false-negative and false-positive HIV PCR results are increasingly likely
despite highly accurate diagnostic assays. The problem is compounded by
the seemingly intractable prevalence of maternal HIV within some settings,
resulting in a considerable absolute burden of HIV-infected infants despite
a low mother-to-child transmission rate.