CCR5 chemokine receptor variant in HIV-1 mother-to-child transmission and disease progression in children. French Pediatric HIV Infection Study Group.

CONTEXT

Studies suggest that adults with the CCR5delta32 deletion are less likely to become infected with the human immunodeficiency virus (HIV) and to develop HIV-related disease progression, but the effect of the mutation in children is not known.

OBJECTIVE

To study the effect of the CCR5 chemokine receptor mutant allele on mother-to-child transmission of HIV type 1 (HIV-1) and subsequent disease progression in infected children.

DESIGN

Multicenter, prospective study of infants born to mothers seropositive for HIV-1.

SETTING

A total of 52 medical centers participating in the French Pediatric HIV Cohort studies.

PARTICIPANTS

The CCR5delta32 deletion was studied in 512 non-African children, born between 1983 and 1996 to HIV-1-infected mothers. Among them, 276 children were infected and 236 were not.

MAIN OUTCOME MEASURES

HIV-1 infection status and, in infected children followed up since birth, incidence of category B and C disease events and severe immunosuppression as defined in the new pediatric Centers for Disease Control and Prevention (CDC) classification, according to CCR5 genotype.

RESULTS

The 32-base pair deleted allele was detected at a frequency of 0.05. Only 1 infant, not infected by HIV-1, was homozygous for the delta32 deletion. The 49 heterozygous children (9.6% of the total; 95% confidence interval [CI], 7.1-12.2) were equally distributed into the infected (9.8%) and uninfected (9.3%) groups. The incidence of stage C symptoms in heterozygous infected children was 9% at 36 months vs 28% in children homozygous for the normal allele (P<.004). The proportion of children at 8 years old with no stage B or C symptoms was 49% for heterozygous children and 11% for children homozygous for the normal allele (P<.003). The progression of severe immune deficiency (CD4 <15%, CDC stage 3) was also significantly different between the 2 groups (P<.001).

CONCLUSIONS

Heterozygosity for the CCR5delta32 deletion does not protect children from infection by the maternal virus but substantially reduces the progression of the disease in HIV-1-infected children.