ABNORMAL IgG SUBCLASSES IN CHILDREN WITH SUSPECTED ACQUIRED IMMUNE DEFICIENCY SYNDROME (AIDS)

Abstract

A unique aspect of pediatric AIDS (PAIDS) is an additional susceptibility to infections characteristic of immunoglobulin (Ig) deficiency: otitis media, sinusitis, sepsis. To evaluate this clinical observation further, IgG subcalsses were determined in 3 infant boys with suspected AIDS and 4 adult homosexual men with AIDS. JP and PB, born at 28 and 29 weeks gestation, had received multiple blood transfusions in the neonatal period and died at 11 and 22 months, respectively, with P. carinii pneumonia The mother of a third infant, MF, has AIDS, likely acquired from her i.v. drug abusing husband. This child has lymphoid interstitial pneumonia and sinusitis. Laboratory evaluation of these infants revealed reversed T helper:suppressor ratios, decreased lymphoproliferative responses to mitogens and hyperimmunoglobulinemia G and A. JP's and PB's serum IgG levels declined as their disease progressed. In addition, JP has absent IgG2, PB had absent IgG3 and MF had absent IgG2 and IgG4. Other IgG subclasses were normal. In the 4 adult subjects, total IgG levels were increased and IgG subclasses were normal to increased.The finding of selective IgG subclass deficiencies in PAIDS is consistent with the improvement seen in some of these patients following Ig replacement therapy. The normal IgG subclass values noted in the adult AIDS patients in association with a lack of characteristic infections indicate that Ig would not be of benefit in these patients.