Congenital adrenal hyperplasia caused by defect in steroid 21-hydroxylase. Establishment of definitive urinary steroid excretion pattern during first weeks of life.

The steroid excretion of two female infants with congenital adrenal hyperplasia due to 21-hydroxylase deficiency has been studied during the first weeks of life. The techniques used were gas chromatography on an open-tubular column and combined gas chromatography-mass spectrometry using selected ion recording. During the first days of life 3beta-hydroxy-5-ene steroids predominate and the levels found were considerably greater than those found in normal infants. Selected ion recording mass spectrometry permitted detection of pregnanetriol and 11-oxo-pregnanetriol several days before these steroids could be determined with accuracy by conventional gas chromatography. Pregnanetriol and 11-oxo-pregnanetriol were first detected on the third day of life. The results of this investigation demonstrate that 21-hydroxylase deficiency may be indicated during the first week of life by an increased 3beta-hydroxy-5-ene steroid excretion, but the definitive excretion pattern required for firm diagnosis may not develop for several days. The amounts of the definitive steroids excreted may not be sufficient to be detected by the more usual methods for several weeks.