Serum Adrenal Steroid Concentrations in Premature Infants*

To evaluate serum adrenal steroid concentrations in preterm infants, 17-hydroxyprogesterone (17-OHP), 17-hydroxypregnenolone, 11-deoxycortisol, cortisol, dehydroepiandrosterone (DHEA), DHEA sulfate, androstenedione, 18-hydroxycorticosterone, and aldosterone values were determined in 9 sick and 13 healthy premature infants. Serum steroid concentrations were compared to previously reported data from healthy full-term infants. 17-OHP, 11-deoxycortisol, and aldosterone values were higher in sick preterm infants than in healthy preterm infants. Compared to healthy full-term infants, the premature infants-had significantly higher 17-hydroxypregnenolone, 17-OHP, and DHEA sulfate concentrations. Cortisol values were not different between the sick and healthy preterm infants and were similar to full-term values. Aldosterone values were also similar between the premature and the full-term infants. The findings of elevated steroid precursors in preterm infants and low cortisol levels in stressed sick preterm infants may indicate a relative immaturity of adrenal enzyme activity and inadequate adrenal reserve for stress.