Following the demonstration by Wilkins,

Lewis, Klein, and Rosenberg (1) that cortisone controls the clinical manifestations and abnormal laboratory findings in virilizing adrenal hyper-plasia, Bartter, Albright, Forbes, Leaf, Dempsey, and Carroll (2) postulated a deficient synthesis of "sugar hormone " (17-hydroxycorticosterone, Compound F) in this disease, reasoning from the unusual response of such patients to the adminis-tration of adrenocorticotropin (ACTH). This hypothesis has been supported by the demonstra-tion of low blood levels of 17-hydroxylated-corti-costeroids ("Porter-Silber chromogens") in un-treated patients with adrenal hyperplasia and the usual failure of these levels to rise, following ad-ministration of ACTH (3,4). The discovery that, routinely, large quantities of pregnane-3a, 17a,20a-triol are excreted in the urine of patients with virilizing adrenal hyperplasia (5) has sug-gested a possible site of the metabolic block in the synthesis of Compound F. The present studies were undertaken to char-acterize the corticosteroids excreted in the urine in adrenal hyperplasia, in an attempt to define more precisely the specific defect in steroid bio-synthesis. METHODS Twenty-four-hour collections of urine from normal control subjects and from patients with adrenal hyper-plasia were investigated in the following manner: Urine for 17-ketosteroid determinations was hydrolyzed first with beta-glucuronidase2 and manually extracted with ether; the remaining urine was continuously ex-tracted at room temperature with ether for 36 hours after the addition of 10 volumes per cent (v/v) of 40 per cent sulfuric acid. The combined extracts were fractionated on alumina columns (6) and suitable frac