PERSISTENCE OF THE ENZYMATIC BLOCK IN ADOLESCENT PATIENTS WITH SALT-LOSING CONGENITAL ADRENAL-HYPERPLASIA

The 24-hour integrated concentration of aldosterone, plasma renin activity, and 17-hydroxprogesteronewas measured simultaneously in 12 patients with congenital virilizing adrenal hyperplasia due to 21-hydroxylase deficiency. Eight were salt-losers and four nonsalt-lowers. Seven normal children served as control subjects. All patients were receiving glucocorticoid replacement therapy (32 mg/m2/day). All but one of the SL-CVAH patients were also being treated with 9α-fluorocortisol. The mean (±SD) IC-PRA of the control subjects was 1.6±0.7 ng/ml/hour and in the NSL-CVAH patients was similar (1.6±0.7 and 2.2±1.0 ng/ml/hour). The IC-PRA of the SL-CVAH patients (21.1±28.8 ng/ml/hour) was significantly (P<0.001) higher than that of the normal subjects. The IC-ALDO/IC-PRA ratio of the control subjects and NSL-CVAH patients were 12.4±5.1 and 8.8±4.8, respectively. The ratio in SL-CVAH patients was significantly lower (2.0±1.4) than that of the control subjects (P<0.001). The lowered IC-AL DO/IC-PRA ratio in the SL-CVAH patients demonstrates the persistence of the 21-hydroxylase deficiency. © 1979 The C. V. Mosby Company.