Preterm infants with low immunoglobulin G levels have increased risk of neonatal sepsis but do not benefit from prophylactic immunoglobulin G.
OBJECTIVE
In a prospective, randomized, placebo-controlled, multicenter study, we evaluated the prevention of neonatal infections with intravenous immunoglobulin G (IVIgG) prophylaxis for preterm infants (gestational age <33 weeks) with umbilical cord blood IgG levels < or =4 g/L.


METHODS
Intravenous IgG or placebo (albumin), 1 g/kg body weight, was given on days 0, 3, 7, 14, and 21 to 81 infants with umbilical cord blood IgG levels < or =4 g/L: (1) IVIgG group, n = 40, mean (SD) gestational age 27.5 (2.2) weeks and birth weight 1.06 (0.39) kg; (2) placebo group, n = 41, mean (SD) gestational age 27.7 (2.5) weeks and birth weight 1.13 (0.38) kg. Infants with umbilical cord blood IgG levels >4 g/L (n = 238) served as a separate comparison group. Neonatal infections according to European Society of Pediatric Infectious Disease criteria were monitored until 28 days of life.


RESULTS
Infants with IgG levels < or =4 g/L at birth who received IVIgG had no significant reduction in infectious episodes or mortality rate when compared with those given placebo. However, infants with a serum concentration of IgG >4 g/L at birth had significantly fewer infectious episodes (culture-proven sepsis) than infants with low serum concentrations of IgG (< or =4 g/L) when compared at the same gestational ages (26 to 29 weeks, P <.003).


CONCLUSIONS
Prophylactic immunotherapy with IVIgG did not improve the immune competence in preterm infants with low serum IgG concentrations at birth. We speculate that a spontaneously high serum IgG concentration at birth reflects placenta function and is an indicator of a more mature immune system capable of protecting the preterm infant against severe neonatal infections.
Sandberg
K
K
Queen Silvia Children's Hospital, Göteborg, Sweden; Children's Hospital, Vienna-Glanzig, Austria.
Fasth
A
A
Berger
A
A
Eibl
M
M
Isacson
K
K
Lischka
A
A
Pollak
A
A
Tessin
I
I
Thiringer
K
K
D003428:Cross Infection / Q000276:immunology / Q000517:prevention & control*; D004311:Double-Blind Method; D005312:Fetal Blood / Q000276:immunology; D006801:Humans; D007121:Immunocompetence; D007074:Immunoglobulin G / Q000097:blood*; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use*; D007231:Infant, Newborn; D007234:Infant, Premature / Q000276:immunology*; D007235:Infant, Premature, Diseases / Q000276:immunology / Q000517:prevention & control*; D011446:Prospective Studies; D012307:Risk Factors; D018805:Sepsis / Q000276:immunology / Q000517:prevention & control*
D007074:Immunoglobulin G; D016756:Immunoglobulins, Intravenous