AMNIOTIC-FLUID CYTOKINES (INTERLEUKIN-6, TUMOR-NECROSIS-FACTOR-ALPHA,INTERLEUKIN-1-BETA, AND INTERLEUKIN-8) AND THE RISK FOR THE DEVELOPMENT OF BRONCHOPULMONARY DYSPLASIA

OBJECTIVE: Our purpose was to test the hypothesis that neonates who de velop bronchopulmonary dysplasia have higher amniotic fluid concentrat ions of proinflammatory cytokines than those who do not develop bronch opulmonary dysplasia. STUDY DESIGN: The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, in terleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmo nary dysplasia in the neonate was examined in 69 patients who were del ivered of preterm neonates(less than or equal to 33 weeks) within 5 da ys of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS: Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of n ewborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 concentra tions were significantly higher in mothers whose infants had bronchopu lmonary dysplasia than in mothers whose infants did not have bronchopu lmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmona ry dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The diffe rences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth lo < 0.05 for each ). CONCLUSIONS: (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of n eonates may begin before birth.