Early postnatal dexamethasone decreases hepatocyte growth factor in tracheal aspirate fluid from premature infants

Objective. To evaluate in preterm infants the effect of dexamethasone on hepatocyte growth factor (HGF), an epithelial cell mitogen, and on vascular endothelial growth factor (VEGF), an endothelial cell mitogen, in tracheal aspirate fluid (TAF). Methods. Thirty preterm infants (birth weight: 10001500 g) with respiratory distress syndrome were randomized to receive dexamethasone or to serve as control subjects. Dexamethasone was started at the age of 12 to 24 hours at a dose of 0.5 mg/kg/d for 2 days and 0.25 mg/kg/d for the subsequent 2 days. HGF and VEGF levels were examined from TAF samples during the first postnatal week. For eliminating the effect of dilution, the concentration of the secretory component of immunoglobulin A was determined. Student t test, 1-way analysis of variance, chi(2), and simple regression analysis were used for statistical analysis. Results. Mean HGF concentrations were similar in the dexamethasone and control groups on days 1 to 2, but the dexamethasone group had a lower mean HGF concentration on days 3 to 4 and 5 to 7. In contrast, no differences existed in mean VEGF levels between the dexamethasone and control groups. Conclusions. In preterm infants who received early postnatal dexamethasone, reduced levels of HGF were seen in tracheal aspirates. This reduction may participate in the suppressive effects of dexamethasone on lung development.