Peripheral Neutrophil Count and Respiratory Failure in Preterm Infant

ABSTRACT

PURPOSE: The purpose of this study was to analyze the association of peripheral neutrophil count with the development of respiratory failure in preterm infants. METHODS: A retrospective study was conducted from January 1993 to December 1999 on 44 preterm infants, who were admitted to the neonatal intensive care unit of St. Francisco hospital. Preterm infants(birth weight 500 to 1,350 gm) who had a complete blood count obtained within 2 hours after delivery. Patients in the lowest of neutrophil count(early neutropenia, <1.0X10(9)/L) were compared with patients in the remaining group. RESULTS: Low neutrophil count were transient in early neutropenia group. The concentration the circulating neutrophil count rose from 0.85+/-0.11X10(9)/L at average of 2 hours after delivery to 5.3+/-2.7X10(9)/L at 24 hours after delivery in the early neutropenia group and from 3.6+/-1.6X10(9)/L to 5.8+/-3.2X10(9)/L in the non-neutropenia group during the same time period. Compare to the non-neutropenia group, the neutropenia group had a lower birth weight(1,046.50+/-180.76 gm Vs 1,156.70+/-124.99 gm), a lower Apgar score(1 min 3.41+/-1.18 Vs 4.30+/-1.46, 5 min 5.41+/-0.87 Vs 6.15+/-0.95), and a higher incidence of bronchopulmonary dysplasia(27.27% Vs 7.0%). Patients who had early neutropenia were more likely to require mechanical ventilation, supplemental oxygen and hospital stay. Also, main effect factors for the two groups were birth weight(Odds ratio=5.457, 95 % CI=1.551-27.525), initial peripheral blood white cells(odds ratio=8.308, 95% CI=2.054-52.699), and bronchopulmonary dysplasia(odds ratio=0.099, 95% CI=0.017-0.397). CONCLUSION: A low count of neutrophil in the systemic circulation of premature infants within 2 hours of birth is associated with more severe respiratory distress.