Combined treatment with surfactant and specific immunoglobulin reduces bacterial proliferation in experimental neonatal group B streptococcal pneumonia.
Neonates suffering from group B streptococcal (GBS) pneumonia often lack type-specific opsonizing antibodies. We studied the influence of combined intratracheal treatment with surfactant and a specific antibacterial polyclonal antibody (IgG fraction) on bacterial proliferation and lung function in an animal model of GBS pneumonia. Near-term newborn rabbits received an intratracheal injection of either the specific IgG antibody, nonspecific IgG, surfactant, a mixture of surfactant and the antibody, or 0.9% saline. At 30 min the rabbits were infected with a standard dose (10(8)) of the encapsulated GBS strain 090 Ia. After 5 h of mechanical ventilation the mean estimated increase in bacterial number in lung homogenate (log10 colonies/g) was 0.76 in the antibody group, 0.92 in the nonspecific IgG group, 0.55 in the surfactant group, and 1.29 in the saline group. A mean decrease in bacterial number (-0.05) was observed in the group that received combined treatment with surfactant and antibody (p < 0.05 versus all other groups). Lung-thorax compliance was significantly higher in both groups of surfactant-treated animals compared with saline or IgG treatment. We conclude that in experimental neonatal GBS pneumonia combined treatment with surfactant and a specific immunoglobulin against GBS reduced bacterial proliferation more effectively than either treatment alone.
Herting
E
E
Department of Pediatrics, University of Göttingen, Göttingen, Germany. eherting@med.uni-goettingen.de
Gan
X
X
Rauprich
P
P
Jarstrand
C
C
Robertson
B
B
D000818:Animals; D000831:Animals, Newborn / Q000382:microbiology*; D000918:Antibody Specificity / Q000502:physiology; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D007074:Immunoglobulin G / Q000276:immunology / Q000627:therapeutic use*; D008168:Lung / Q000473:pathology; D008170:Lung Compliance; D009504:Neutrophils / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D011018:Pneumonia, Pneumococcal / Q000382:microbiology* / Q000473:pathology / Q000628:therapy*; D011663:Pulmonary Surfactants / Q000627:therapeutic use*; D011817:Rabbits; D013292:Streptococcus agalactiae / Q000254:growth & development*; D013500:Surface Tension
D007074:Immunoglobulin G; D011663:Pulmonary Surfactants; D010100:Oxygen