AN IMPROVED METHOD FOR THE DETECTION OF HETEROZYGOSITY OF CONGENITAL VIRILIZING ADRENAL HYPERPLASIA

Abstract
SUMMARY: A modified short ACTH test for the detection of heterozygote carriers of 21‐hydroxylase deficiency (21‐OHD) was applied to twenty‐one controls and fourteen parents of children with 21‐OHD. The following modifications were introduced: (1) Endogenous ACTH was suppressed by dexamethasone administration prior to the test, (2) Plasma 17‐hydroxyprogesterone (17‐OHP), cortisol (F), progesterone (P), corticosterone (B) and Δ4‐ androstenedione (A) were measured, (3) Variables studied were the ratio of plasma increments (A) between precursors and end products, (4) Data were analysed by a step‐wise discriminant analysis. Significant alterations in the metabolic pathway of F, B and A were demonstrated. The discriminant analysis showed that the addition of B pathway data did not improve the discrimination potency of the test performed on F pathway data. The combination of variates which provided the best discrimination was the logarithmic sum of Δ 170HP/ΔF at 15 and 30 min. It led to a 94% correct classification for normals and carriers.