A Case of Primary Pigmented Nodular Adrenocortical Disease as a Cause of Cushing Syndrome and a Coincident Pituitary Adenoma

Abstract

We present a case of Cushing syndrome due to sporadic primary pigmented nodular adrenocortical disease not accompanied by Carney complex (CNC). The patient had a coincident pituitary adenoma. A 30-year-old woman was seen because of weight gain, swelling of the face, hypertension, and muscle weakness. Physical examination revealed the classic features of Cushing syndrome. Basal serum and urinary free cortisol levels were elevated and adrenocorticotropic hormone (ACTH) levels were suppressed. After overnight (1 mg), low dose (2 mg), and high dose (8 mg) dexametasone tests urinary and serum cortisol levels were not suppressed but elevated further. A computed tomography scan showed micronodular hyperplasia in both adrenal glands. A 2-mm mass lesion suggesting a microadenoma was also shown on the magnetic resonance imaging of the pituitary gland. A petrosal sinus sampling was performed. In the samples obtained from petrosal sinus and periphery, ACTH levels were all suppressed and did not increase after CRH (corticotropin-releasing hormone) stimulation. None of the findings of the CNC were present. The Cushing syndrome was thought to be due to bilateral adrenal micronodular hyperplasia and a bilateral adrenalectomy was performed. Multiple, gray-brown colored micronodules were found in both adrenals. After the operation, the patient was given steroid replacement therapy and her Cushingoid features regressed. Primary pigmented nodular hyperplasia is a rare diagnosis that should be considered in patients with ACTH-independent bilateral adrenal disease not exhibiting features of the CNC. The presence of a coincident pituitary microadenoma may complicate the diagnosis and does not always indicate a pituitary cause.