CYCLIC ACTH-INDEPENDENT CUSHING SYNDROME IN AN ADOLESCENT REVEALING MULTINODULAR ADRENAL HYPERPLASIA: A CASE REPORT

Background:ACTH-independent Cushing syndrome is rare in children and adolescents, and multinodular adrenal hyperplasia represents an unusual etiology. When hypercortisolism follows a cyclic pattern, diagnosis may be delayed because hormonal abnormalities can fluctuate over time [1,2]. Case Presentation:We report the case of a 16-year-old girl with Cushing syndrome evolving since the age of 8 years, initially marked by alternating symptomatic phases lasting about 15 days and spontaneous remissions of nearly 3 months. Over time, the disease became clinically persistent. Hormonal evaluation showed ACTH-independent hypercortisolism with loss of cortisol circadian rhythm, urinary free cortisol elevated to 8.6 times the upper limit of normal, failure to suppress after overnight dexamethasone testing, and low ACTH levels. Adrenal computed tomography revealed predominant enlargement of the left adrenal gland, associated with atrophy and micronodular changes of the right adrenal gland. Initial treatment with ketoconazole resulted in adrenal insufficiency, requiring hydrocortisone replacement, and was later reintroduced at a lower intermittent dose according to a block and replace strategy. Because hypercortisolism remained insufficiently controlled, left adrenalectomy was performed. Histopathological examination confirmed multinodular adrenal hyperplasia. The postoperative course was favorable, with progressive clinical improvement and biochemical normalization under hydrocortisone replacement.