Congenital adrenal hypoplasia: An isolated defect of organogenesis

Data are presented on four boys, including three siblings, two of whom were identical twins who had clinical, biochemical, and hormonal features of congenital adrenal hypoplasia. One twin died and at necropsy a macroscopically normal pituitary was found, but adrenal tissue could not be identified. Normal plasma levels of growth hormone, thyroid-stimulating hormone, and luteinizing hormone appropriate for the degree of sexual maturation were demonstrated in the two involved siblings of this twin. Insulin-induced hypoglycemia caused a prompt and adequate rise in, plasma adrenocorticotropic hormone levels without a concomitant rise in plasma cortisol levels. The basal plasma aldosterone levels were low and failed to increase following the stimulus of erect posture. Adrenal hypoplasia in these patients represents an isolated defect of organogenesis without demonstrable disturbance in anterior pituitary.