Congenital adrenal hyperplasia, 21-hydroxylase deficiency: classical and non-classical forms

ABSTRACT

21- hydroxylase deficiency is by far the commonest type of congenital adrenal hyperplasia. Both classical and non-classical forms of 21-hydroxylase deficiency have been recently recognized. Sixteen cases with classical form of 21-hydroxylase deficiency, and 7 cases with non-classical form were included in the study. Patients with classical form had their age ranging from 0.1-10.6 yr [4.3 +/- 3.1], 14 cases had 46 xx chromosomal constitution [11 reared as girls, 3 reared as boys] and 2 cases had 46 xy chromosomal constitution and were reared as boys. One third of cases were of salt-wasting type, and the rest of simple virilizing type. Mean serum level of testosterone was 1.9 +/- 1.5 ng/ml [0.1-5], 17-hydroxyprogesterone 12.4 +/- 10.7 ng/ml [2-42], delta4-androstenedione 13.5 +/- 9.6 nglml [4-28] and dehydroepiandrosterone sulphate 139.4 +/- 108.7ug/dl [16.4-320]. The age of non-classical form patients ranged from 2-20 yr [10.6+7.1] 2 were boys and 5 girls. Basal values of serum testosterone, 17 hydroxyprogesterone, delta 4- androsienedion and dehydroepiandrosterone sulphate were high. Delineation of genetic sex and diagnosis of the underlying enzymatic defect are essential to prevent ambiguity in sex assignment in cases of congenital adrenal hyperplasia. Non-classical form of congenital adrenal hyperplasia is not a rare disease, may present at variable age with variable presentation