Quantification of CD4 Recovery in Early-Treated Infants Living With HIV

BACKGROUND: Perinatally HIV-acquired infants benefit from an early antiretroviral treatment initiation. Thanks to a short viral exposure time, their immune system can be maintained or reconstituted, allowing a "normal" immune development.

METHODS: In this study, we mathematically modeled and quantified individual CD4+ T-cell reconstitution of a subset of 276 children who started treatment within 6 months of age and achieved sustained viral suppression. Considering natural age differences in CD4+ T-cell dynamics, we fitted distances to age-matched healthy reference values with a linear model approaching an asymptote.

RESULTS: Depleted CD4+ percentages (CD4%) and CD4+ counts (CD4ct) restored healthy levels during treatment. CD4ct recovered with a median rate of 4 cells/µL/d, and individual recovery rates were correlated negatively with their initial CD4ct. CD4 values at onset of treatment decrease with age, whereas recovery times and levels seem to be age-independent. CD4 recovery correlates positively with viral suppression, and the stabilization of CD4 levels usually occurs after viral suppression. CD4 levels stabilize within 3-13 months after treatment initiation. The recovery dynamics of the CD4% is comparable with those of the CD4ct.

CONCLUSIONS: In early-treated children with successful viral suppression, the CD4 depletion is typically mild and CD4+ T cells tend to "fully" recover in numbers.