1310 KINETIC AND METABOLIC STUDIES OF AN INTRAVENOUSLY ADMINISTERED IMMUNOGLOBULIN PREPARATION IN A NEONATAL LAMB MODEL

Bacterial sepsis and meningitis persist as major neonatal problems despite a wide variety of effective antibiotics. Recent studies have shown that a deficiency of opsonic antibody is associated with increased risk to developing group B strep-tococcal (GBS) sepsis and meningitis. We have previously shown that a new human immunoglobulin preparation modified for intravenous administration (MISG) protected suckling rats from lethal GBS infection. The present studies were designed to evaluate the kinetics and metabolic effects of MISG in the neonatal lamb. MISG (0.5 to 1.0 gm/kg) was given IV over 15 min and blood samples were obtained at 15, 30 and 60 min, and at 4 and 24 hr. No overt toxic or anaphylactic effects were observed. IgG levels peaked at about 800 mg/dl (0.5 gm/kg/dose) and 1500 mg/dl (1.0 gm/kg/dose). Changes in serum osmolality and oncotic pressure were minimal, but serum glucose levels were elevated at 30 and 60 min after infusion. Post infusion Na, K and Cl were not different from baseline levels. These data show that IV administration of MISG in a neonatal model elevates serum IgG levels without inducing serious side effects. Passive administration of human IgG to neonates may provide a valuable adjunct to standard antibiotic therapy of bacterial disease and future studies appear warranted.