Low prevalence of selective IgA deficiency in infected children born to HIV-seropositive mothers: an in vivo model for speculation on selective IgA deficiency pathogenesis

Anecdotal reports of restored immunoglobulin production in individuals with common variable immunodeficiency after acquiring HIV infection suggest that perturbation of the immune system occurring during HIV infection may force some underlying functional defects. These findings raise intriguing questions about the pathogenesis of common variable immunodeficiency. No study has investigated the possible influence of HIV infection on the development of selective IgA deficiency, a primary immunologic defect genetically related to common variable immunodeficiency. IgA serum levels were evaluated in a large cohort of children born to HIV-infected mothers from 1985 to 2006. To avoid differences possibly due to different follow-up durations we considered only infected and non-infected children aged over 4 years at last-follow-up. The study included 1,157 non-infected children and 964 infected children, aged ≥ 4 years at last-follow-up and with availability of two or more serum IgA determinations over six months of age. No child displayed immunoglobulin values compatible with diagnosis of common variable immunodeficiency. However, 0/964 infected children vs. 5/1157 non-infected children had selective IgA deficiency (P=0.048). It may be speculated that several immunological alterations, occurring simultaneously in perinatal HIV infection, surpass the functional defect exhibited in some children with selective IgA deficiency. Our data may shed light on the pathogenesis of selective IgA deficiency.