Dexamethasone therapy is associated with a rise in urinary epidermal growth factor concentrations in the preterm infant

Abstract

The effect of glucocorticoid hormones on epidermal growth factor (EGF) concentrations has not been described in the premature infant. We examined this relationship in a group of infants treated with dexamethasone for airway edema (three to five doses) or chronic lung disease (six weeks of a tapering protocol). We collected urinary samples in 45 infants (25 for airway edema, 20 for chronic lung disease) before, during and after the use of dexamethasone. The EGF values were unchanged in infants that were given dexamethasone for airway edema. In contrast, all infants treated for chronic lung disease increased their EGF values by 1 week of therapy. At the end of the dexamethasone taper, ten of the infants had recovered successfully from ventilatory support. This group of infants had post-therapy EGF values that were significantly higher than pretherapy values. In the ten infants that were still ventilator dependent at the end of therapy, EGF values were not different from pretherapy values. We conclude that dexamethasone therapy was associated with an increase in urinary EGF values in the preterm infant treated for at least 1 week. The positive correlation of tapering from ventilatory support with increases in EGF values suggests that EGF may be a marker of dexamethasone effect or an effector of dexamethasone action.