111 NEUTROPHIL ELASTASE IN DIAGNOSIS OF NEONATAL INFECTION

Abstract

Elastase (E) released from neutrophils during phagocytosis is rapidly bound and inactivated by α1-proteinase inhibitor. As previously shown, the complex is a sensitive and rapidly responsive indicator of neonatal sepsis using a time-consuming ELISA method (J. Pediatr. 1986, 108:987). In this 3 center prospective study we measured E with a rapid assay (IMAC-Elastase, Merck; 15 min) and compared it with immature/total neutrophils (I/T) and C-reactive protein (CRP) In infants with suspected infection. Normal IMAC-E values (n=319) were obtained from 125 controls (upper limits; day 0-2, 130 μg/l; day 3-5, 95 μg/l; day 6-28, 65 μg/l). An additional 252 neonates of diverse birth weights and gestational ages were evaluated for infection. Sepsis was proved in 10 and pneumonia (positive tracheal aspirate culture and x-ray) in 23.*Values derived from infected (sepsis/pneumonia) ve. non-infected IMAC-E is a useful adjunct in diagnosing neonatal infection, but combining E with I/T and/or CRP markedly increases PPV.