PRIMARY PIGMENTED NODULAR ADRENOCORTICAL DYSPLASIA - A RARE CAUSE OF CUSHINGS-SYNDROME

History and clinical findings: A 29-year-old woman was found to have a rterial hypertension (175/115 mmHg). The 24-hour profile showed no diu rnal cortisol variations with normal concentrations and 24-hour urinar y cortisol was normal. 14 months later there was definite hypercortiso lism with discrete Gushing signs and no amenorrhoea. She also had sign s of depression. Investigations: Routine laboratory tests were unremar kable. ACTH and dehydroepiandrosterone levels were reduced and there w as marked hypercortisolism (600 mu g/24h). Bone densitometry showed os teoporosis. The low- and high-dose dexamethasone inhibition tests show ed no suppression of 24-hour urinary cortisol, raising the suspicion o f adrenal cortical adenoma or carcinoma. Magnetic resonance imaging (M RI) of both adrenals was normal, and scintigraphy showed physiological storage. MRI of the skull was normal. Treatment and course: As ACTH-i ndependent hypercortisolism had been proven, unilateral adrenalectomy was performed. The specimen showed primary pigmented nodular adrenocor tical dysplasia (PPNAD). While cortisol levels and blood pressure were at first normal, hypercortisolism had recurred 5 months postoperative ly. The other adrenal was removed and showed a similar histology. A ma lignant melanoma of the shoulder was also found, perhaps part of a Car ney syndrome. Conclusion: PPNAD should be included in the differential diagnosis of an ACTH-independent Gushing's syndrome with normal adren al on imaging, perhaps as part of a Carney syndrome.