Abnormalities of neutrophil adherence in newborns

Polymorphonuclear neutrophil (PMN) adherence to glass and nylon wool was examined in 19 healthy term newborns, 19 normal children aged 2 weeks to 17 years, and 33 adults in good health who were taking no medication. Using a whole blood glass adherence assay, neonatal PMN adherence (0.18 +/- 0.16%) was significantly less than PMN adherence in children (7.4 +/- 4.0%, P less than .0001) and in adults (16.0 +/- 4.5%, P less than .0001). Similar results were obtained when separated neonatal and adult PMNs were used with both glass and nylon wool column adherence assays, indicating that decreased neonatal PMN adherence is due to a cellular defect. In other experiments there was significantly greater reduction in adherence of separated PMNs with addition of neonatal serum than with adult serum, indicating that a humoral inhibitor also contributes to decreased adherence of neonatal PMNs. Decreased neonatal PMN adherence may be one cause of the increased susceptibility of neonates to serious bacterial infections.