Intravenous administration of human IgG to newborn infants: changes in serum antibody levels to group B streptococci.
A human IgG preparation was given intravenously to 36 newborn infants admitted to the neonatal intensive care unit because of suspected septicaemia. IgG was given as a single dose of 0.4 g/kg body weight. Patient serum was obtained immediately before and 30 min after terminating the infusion. Blood was also withdrawn 2 days after giving the IgG in eight of the infants. The sera were tested by radioimmunoassay for IgG antibody levels to surface antigens of group B streptococci (GBS) types Ia, Ib, II and III and to R-protein. The mean increases in anti-type Ia, Ib, II, III and R-protein antibodies 30 min after the end of infusion were 81%, 73%, 49%, 60% and 69% of the preinfusion levels, respectively. This was followed by a rapid decrease during the following 2 days to 25%-32% of the initial increases. Based on the above findings, a controlled trial of passive immunisation in the management of neonatal GBS septicaemia seems justified. The rapid decline in antibody levels would necessitate a second infusion 24 h after the initial immunoglobulin administration if the suspicion of septicaemia persists.
D000907:Antibodies, Bacterial / Q000032:analysis*; D000918:Antibody Specificity; D006801:Humans; D007074:Immunoglobulin G / Q000008:administration & dosage*; D007231:Infant, Newborn; D007263:Infusions, Parenteral; D018805:Sepsis / Q000628:therapy*; D013290:Streptococcal Infections / Q000628:therapy*; D013292:Streptococcus agalactiae / Q000276:immunology*
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G