EVALUATION OF HYPOTHALAMO-PITUITARY-ADRENOCORTICAL FUNCTION IN CHILDREN BY HUMAN CORTICOTROPIN-RELEASING HORMONE (MCI-028) TEST

A dose of 1.5 mu g/kg of MCI-028, human corticotropin-releasing hormon e (hCRH), was administered intravenously to 38 children with non-endoc rine short stature with normal function in the hypothalamo-pituitary-a drenocortical axis and to 71 children with a disorder in the same axis . Blood levels of adrenocorticotropic hormone (ACTH) and cortisol were determined to evaluate the axis. The 95% confidence limits of peak re sponses of ACTH and cortisol in non-endocrine short stature were betwe en 17.2 and 135.3 pg/ml, and between 13.1 and 35.6 mu g/dl, respective ly, and were used as standards for children. When compared with these standards. the hormonal responses in children with various disorders i n the hypothalamo-pituitary-adrenocortical axis were as follows: in tw o children with Cushing's syndrome caused by adrenal tumor, ACTH value s were decreased and were not responsive to hCRH, while cortisol value s,though within the normal limit, were not responsive; in children wit h primary adrenal insufficiency or congenital adrenal hyperplasia, cor tisol Values were decreased and not responsive, whereas ACTH values te nded to be increased and ACTH response high except for 21 alpha-hydrox ylase deficiency of congenital adrenal hyperplasia. In two cases of pi tuitary dwarfism complicated with ACTH deficiency, both ACTH and corti sol values were decreased and poorly responsive; and in children who w ere receiving glucocorticoid, both ACTH and cortisol Values tended to be decreased and to respond poorly to hCRH. As for side effects, hot f lushing was observed among 8.0% of the subjects after administration o f hCRH. But this symptom was not severe and no other side effects of c linical importance were observed. In conclusion, this study demonstrat ed that the hCRH test was also safe and useful in evaluating hypothala mo-pituitary-adrenocortical function in children.