Immunoglobulin therapy of neonatal group B streptococcal infections: an overview.

Group B streptococci (GBS) are a major cause of sepsis and meningitis in newborn babies. Neonatal GBS infections are often rapidly progressive, suggesting that the immunity to GBS is deficient. Studies have shown that opsonic antibody is required for efficient phagocytosis and killing of GBS, and neonatal GBS infections have been associated with diminished levels of anti-GBS antibody. Intravenous immunoglobulin (IVIG) has been shown to provide protective immunity in experimental GBS infection models. However, lot to lot variation in opsonic antibody levels occurs in standard IVIG preparations. Recently hyperimmune anti-GBS IVIG has been prepared with high levels of opsonic and protective antibody to GBS. Hyperimmune IVIG preparations will allow physicians to give higher quantities of specific anti-GBS antibody without having to administer large fluid volumes or large amounts of nonspecific immunoglobulin. In addition specific immunoglobulin preparations will ensure that the IVIG contains reliable antibacterial activity. Although human studies are limited they suggest that IVIG therapy in neonates may be safe and effective in treating neonatal sepsis. However, further studies are necessary to determine the role of IVIG in preventing or treating neonatal infections.