PITUITARY MICROADENOMA CAUSING CUSHINGS-D ISEASE IN CHILDREN

Problem: One girl and four boys aged 8 to 16 years had the typical cli nical symptoms of ACTH-dependent Cushing's disease. Methods: In all ca ses the hypothalamopituitary origin was confirmed by endocrine testing (dexamethasone suppression test, corticotropin releasing hormon test, urinary excretion of cortisol metabolites, ACTH concentrations in pet rosal sinus). The pituitary adenoma was identified by MR imaging. Resu lts: In all patients dexamethasone did not suppress adequately the ele vated cortisol levels, however, ACTH-levels were in the normal range a nd increased markedly after CRH-stimulation. This allows the distincti on between hypothalamo-pituitary and adrenal hypercortisolism. Urinary excretion of cortisol-metabolites was significantly increased. All pa tients underwent MR imaging but a pituitary adenoma was identified in three patients only. In the other patients bilateral petrosal sinus sa mpling revealed markedly higher CRH-stimulated ACTH-concentrations on one side indicating the site for surgical intervention. Selective aden omectomy was performed by transsphenoidal approach but in three patien ts hypercortisolism persisted after the operation. Consequently, two p atients were reoperated successfully and one patient underwent cranial irradiation. Conclusions. Diagnostic clarification in Cushing's disea se in childhood is difficult and hormonal analysis often gives conflic ting results. Even MR imaging does not reliably detect a pituitary ade noma. Selective transsphenoidal adenomectomy is the preferable treatme nt for Cushing's disease. However the remaining pituitary functions ha ve to be controlled after surgery.