Intravenous immune globulin prophylaxis of late-onset sepsis in premature neonates.

To determine whether a single dose of intravenously administered immune globulin (IVIG) decreases late-onset sepsis in premature infants, we prospectively entered 753 neonates with birth weight 500 to 2000 gm, gestation < or = 34 weeks, and age < or = 12 hours into a multicenter, double-blind, controlled trial. Infants were randomly selected to receive a single intravenous infusion, 10 ml/kg, of either IVIG (500 mg/kg) or albumin (5 mg/kg) and were observed for 8 weeks for infection. Maternal and neonatal risk factors for infection did not differ between groups. Although serum IgG values before infusion were related to gestation (R = 0.62), the change in serum IgG or half-life of IgG after IVIG infusion was not (R < or = 0.09). The serum IgG concentration was increased (p < 0.05) in IVIG-treated patients for 8 weeks. There were 88 episodes of late-onset sepsis in 79 neonates (10.5%). Causative organisms included the following: Staphylococcus epidermidis (37 episodes), Enterococcus (9), Staphylococcus aureus (7), Candida (6), Escherichia coli (6), and multiple organisms (11). Sepsis, death, and death as a result of infection were unaffected by treatment. We conclude that a single infusion of IVIG, 500 mg/kg, shortly after birth was not effective prophylaxis for late-onset infection in premature neonates. Future studies of late-onset sepsis prophylaxis should consider IVIG with known pathogen-specific antibody concentrations against organisms causing these infections, in particular S. epidermidis.

Viral respiratory diseases in children: classification, etiology, epidemiology, and risk factors.

The epidemiology, molecular structure, cell tropism, and pathophysiology of many human disease-causing viruses have been painstakingly and elegantly characterized during the past 50 years. Vaccines and antiviral drugs of varying efficacy were developed and tested. Despite the relegation of smallpox to a freezer chest and the progress in the control of measles and hepatitis B, the viruses that cause respiratory tract infections remain significant causes of illness and death in pediatric populations worldwide. This discussion surveys the virus groups that contain nearly 200 distinct viruses that cause sporadic and epidemic respiratory infections in children. The epidemiology of infection with the influenza A and B, parainfluenza, and respiratory syncytial viruses and adenoviruses and their impact on infants and children and the groups at highest risk for morbid outcomes are discussed.

Comparison of group B streptococcal hyperimmune globulin and standard intravenously administered immune globulin in neonates.

Standard intravenously administered immune globulin (IVIG) contains varying amounts of group B streptococcus (GBS) antibody. A GBS hyperimmune IVIG was produced by immunizing plasma donors. The GBS type-specific opsonic activity was > or = 90% in the hyperimmune IVIG at a 1280 dilution-1 versus at a 10 dilution-1 in standard IVIG. Suckling rat survival after GBS type-specific infection was 100% when the rats were treated with hyperimmune IVIG versus < or = 20% with standard IVIG. To evaluate the effect of this product on GBS antibody levels and clinical toxic effects, we randomly administered either GBS hyperimmune IVIG, 500, 250, or 100 mg/kg, or standard IVIG, 500 mg/kg, to 20 neonates with suspected sepsis. No adverse effects were observed. Total and subclass serum IgG levels reflected only the dose; serum GBS type-specific IgG and opsonic activity reflected both the product and dose of IVIG administered. Standard IVIG did not significantly increase serum GBS type-specific IgG, whereas hyperimmune IVIG, 500 mg/kg, produced a fourfold rise for > 6 weeks; more variable increases were observed after 250 and 100 mg/kg doses were given. Serum GBS type-specific opsonic activity correlated with serum GBS type-specific IgG levels (R2 = 0.74; p < 0.0001). Further studies of this or similar products will be necessary to determine whether GBS type-specific antibody improves the outcome of GBS-infected neonates.

Early-onset group B streptococcal sepsis: a current assessment.

Group B streptococcus (GBS) is a common cause of early-onset sepsis in neonates. The most recent reviews describing incidence, diagnosis, treatment, and outcome evaluated data on patients from the early 1980s. To obtain current information about this disease, we retrospectively evaluated data on neonates with GBS early-onset sepsis from nine hospitals in the United States between Jan. 1, 1987, and Dec. 31, 1989. There were 245 infants with GBS bacteremia identified among 61,809 live births, resulting in an incidence of 0.32%. Ninety-six infants (39%) were preterm (less than 38 weeks of gestational age). Maternal risk factors for infected preterm and term infants were similar. Antibiotics were administered during parturition in 10% of infants with bacteremia. Mothers of preterm infants received antibiotics up to 48 hours before delivery; mothers of term infants received antibiotics less than 4 hours before delivery. All preterm infants with bacteremia had symptoms; 22% of term infants with bacteremia had no symptoms. Group B streptococcal meningitis was confirmed in 6.3% of infants. Although 86% survived, GBS sepsis increased the birth weight-specific mortality rate up to eightfold in preterm infants and more than 40-fold in term infants. Although the incidence of GBS early-onset sepsis is not changing, we speculate that the improved birth weight-specific survival rate and the changing clinical presentation are due to improved intrapartum and neonatal management.