Abstract 1809 Poster Session IV, Tuesday, 5/4 (poster 284)

Recently, it has been postulated that exposure to a prenatal inflammatory process (i.e., chorioamnionitis) may lead to lung injury and predispose to the subsequent development of chronic lung disease (CLD).

Objective: Our purpose was to test the hypothesis that preterm infants who develop CLD have early signs of pulmonary inflammatory process, increased concentration of IL-8 and elevated neutrophil counts in the tracheal aspirate in the immediate postnatal period, compared to those who do not develop CLD.

Method: The relationship between concentration of IL-8 and neutrophil count in the tracheal aspirate and the development of CLD in the preterm infants was examined in 27 preterm infants (GA<34 weeks) who were mechanically ventilated. Tracheal aspirates were collected via endotracheal tube at birth, 6th hour, 24th hour, 72nd hour of life and concentrations of IL-8 were measured by ELSA (R&I Systems, Minneapolis) and neutrophil by cytospin analysis.

Result: Compared to non-CLD group (n=11), CLD group (n=16) had a lower gestational age (27.6 ± 1.4 weeks vs 32.0 ± 2.4 weeks), lower birth weight (1,112 ± 57 grams vs 1,666 ± 100 grams), higher incidence of chorioammionitis (10/16 vs 2/11), increased numbers of neutrophils in tracheal aspirates at birth (80,337 ± 33,748 pg/ml vs 2,663 ± 1,991 pg/ml) and at 6 hour of life (2,464 ± 1,833 pg/ml 247 ± 140 pg/ml) (p<0.05). Higher IL-8(>52.1pg/mL), increased numbers of neutrophils (>1,200/mL) at birth and neutrophils (>6,000/mL) at 6 hours of life increased the risk for CLD (OR, 12.2, 95% CI, 1.8-83.9; OR, 8.0, 95% CI, 1.4-45.8; OR, 18.0, 95% CI, 1.7-187.9, respectively). In conclusion, chorioamnionitis may be an important risk factor for the development of CLD. The lung injury responsible for the development of CLD may begin at the fetal or the immediate postnatal period.