Interleukin-8 and neutrophils in the tracheobronchial aspirate at birth and the risk for the development of chronic lung disease of prematurity

We tested the hypothesis that preterm infants who develop chronic lung dise ase (CLD) have higher concentrations of interleukin-8 (IL-8) and higher neu trophil counts in the tracheobronchial aspirate at birth than those who do not develop CLD. The relationship between concentrations of IL-8 and neutro phil counts in the tracheobronchial aspirate at birth and the development o f CLD was examined in 27 preterm infants. Concentrations of IL-8 were measu red by specific immunoassay and neutrophil counts by cytospin analysis. Med ian concentrations of IL-8 and neutrophil counts in the tracheobronchial as pirate at birth were higher in preterm infants who developed CLD than in th ose who did not develop CLD (p < 0.005 for each). These differences persist ed significantly after adjustments were made for the effects of gestational age at birth, the presence of respiratory distress syndrome and patent duc tus arteriosus (p < 0.05 for each). The fetal pulmonary inflammatory respon se, as measured by increased IL-8 concentrations and neutrophil counts in t he tracheobronchial aspirate at birth in preterm infants, might be a risk f actor for the development of CLD. These results support the hypothesis that the lung impairment responsible for CLD in preterm infants might begin in the prenatal period.