Vascular endothelial growth factor in preterm infants with respiratory distress syndrome

Respiratory distress syndrome (RDS) secondary to surfactant deficiency is a common cause of morbidity and mortality in premature infants. Increasing evidence suggests that vascular endothelial growth factor (VEGF) may contribute to surfactant secretion and pulmonary maturation. However, differences in cord blood VEGF concentrations in infants with and without respiratory distress syndrome have not been reported. We hypothesized that premature infants with higher VEGF levels in cord blood had a lower risk of developing RDS. Cord blood samples were obtained from preterm infants born at 32 weeks of gestation or earlier. Infants were excluded if there was evidence of prenatal maternal infection or any infection within the first 3 days of life. Cord blood VEGF levels were measured using an enzyme-linked immunosorbent assay (ELISA). We found that neonates with clinically diagnosed RDS had a lower gestational age (GA), lower birth weight (BW), higher incidence of mechanical ventilation requirements, longer duration of mechanical ventilation, and lower Apgar scores at 1 and 5 min. Infants with RDS had significantly lower cord blood VEGF levels. GA, BW, premature rupture of membranes (PROM), and antenatal steroid treatment were not associated with changes in cord blood VEGF levels. The specificity of cord blood VEGF above 34 pg/ml for predicting the absence of RDS was 86%, the sensitivity was 53%, the positive predictive value was 84%, and the negative predictive value was 56%. Our data demonstrated that cord blood VEGF elevation was significantly correlated with an absence of RDS.