Neonatal salt loss in the hypertensive form of congenital adrenal hyperplasia.

The 11 beta-hydroxylase deficiency (11OHD) form of congenital adrenal hyperplasia is diagnosed infrequently during the newborn period. A child presumed to have the 21-hydroxylase deficiency form of congenital adrenal hyperplasia was studied extensively as an infant. The diagnosis was based on ambiguous genitalia, elevated 17-ketosteroids, evidence of urinary 11-ketopregnanetriol, and salt loss. Severe hypertension was detected at 11 years, and 11 beta-hydroxylase deficiency was confirmed with elevated plasma 11-deoxycorticosterone and 11-deoxycortisol, low cortisol, and normalization of blood pressure following glucocorticoid replacement. Impaired aldosterone biosynthesis and salt loss were demonstrated during dexamethasone therapy. Salt loss during infancy does not distinguish between the 11 beta- and 21-hydroxylase deficiency forms of congenital adrenal hyperplasia.