To determine the long-term impact of antiretroviral treatment (ART) including a protease inhibitor (PI) on growth in children infected with the human immunodeficiency virus type I (HIV-1), a prospective multi-centre study was conducted in Switzerland on HIV-1-infected children treated with ritonavir (350 mg/m2 twice a day) or nelfinavir (20-30 mg/kg three times a day) in addition to two nucleoside reverse transcriptase inhibitors. Length or height of HlV-1-infected children from before (weeks -72, -48, -24, and 0) and after (weeks +24, +48, and +72) introducing a PI to the ART were compared. To allow for age- and gender-independent assessment, values were expressed in standard deviations from the mean. Complete data sets on body length were available for 44 children after 72 weeks of treatment with a PI. Preceding initiation of a PI, there was an overall decline in growth to -0.3 SD. Following start of a PI, an increase in growth was noted from weeks 0 to +24 (+0.33 SD, P=0.02) and from weeks +48 to +72 (+0.21 SD, P=0.03). The increase in growth was restricted to children with stunting before a PI was introduced (P=0.03), and was more marked in children younger than 3 years of age.
Conclusion: children infected with human immunodeficiency virus type 1 showed catch-up growth after addition of a protease inhibitor to their antiretroviral treatment, but this phenomenon was observed almost exclusively in children under 3 years of age.