Background and methods: Cushing's syndrome is rare in children and adolescents. We analyzed the clinical presentation, diagnostic evaluation, and treatment of 59 patients with Cushing's syndrome between the ages of 4 and 20 years who were admitted to the National Institutes of Health during the period from 1982 to 1992. The cause of hypercortisolism was identified by low- and high-dose dexamethasone suppression tests, the ovine corticotropin-releasing hormone (CRH) stimulation test, imaging studies, and bilateral sampling of the inferior petrosal sinuses combined with administration of CRH.
Results: Fifty patients had Cushing's disease, six had primary adrenal disease, and three had ectopic corticotropin secretion. The initial signs were excessive weight gain in 90 percent of the patients and growth retardation in 83 percent. Most patients (81 percent) had normal bone age at the time of diagnosis. Forty-seven percent had hypertension, whereas only 19 percent had mental or behavioral problems. The high-dose dexamethasone suppression test and the CRH stimulation test identified 68 and 80 percent, respectively, of the patients with Cushing's disease. Magnetic resonance imaging of the pituitary indicated the presence of tumor in 52 percent of the patients with pituitary adenomas. The maximal central-to-peripheral ratio of plasma corticotropin during sampling of the interior petrosal sinuses was > or = 2.5 in all the patients with Cushing's disease and < 2.5 in those with ectopic corticotropin secretion. Remission of hypercortisolism was achieved in 48 of the 49 patients who underwent transsphenoidal surgery for Cushing's disease, in all 6 of the patients who underwent adrenalectomy for primary adrenal disease, and in the 2 patients in whom the ectopic source of corticotropin could be identified.
Conclusions: Weight gain and growth retardation are common clinical characteristics of Cushing's syndrome in children and adolescents. Diagnostic evaluation of such patients with CRH stimulation alone and combined with inferior petrosal sinus sampling and imaging studies is accurate, and therapy is usually successful.