Endocrine Abstracts

We describe the case of a 48-year-old woman, who presented with a history of six months' weight gain, easy bruising and difficulty in rising from a seated position. Examination revealed typical clinical features of Cushing's syndrome. She was hypertensive at 150/100 mmHg and diabetic. She was also agitated, emotionally labile, and disinhibited, requiring sedation. Her sister has MEN-1 (hyperparathyroidism and lung carcinoid tumour).

Low-dose and high-dose dexamethasone suppression tests confirmed Cushing's syndrome (baseline cortisol level 444 nmol/l, 2+48 589, 8+48 679). Baseline ACTH was undetectable, suggesting autonomous adrenal secretion. Pituitary MRI showed no evidence of an adenoma. Adrenal CT showed bilateral nodular hyperplasia. A CRH test showed no significant rise of cortisol, and ACTH levels remained undetectable. A thymic mass was demonstrated on CXR and chest CT: biopsy of this was consistent with a neuroendocrine tumour.

Concurrently, hypercalcaemia was noted (2.85-2.93 mmol/l, corrected). Her PTH was elevated at 27.3 pmol/l. A labelled sestaMIBI scan revealed uptake in the region of the anterior mediastinum and adjacent to the right thyroid lobe. Urine 5-HIAA was normal. Raised glucagon (69 pmol\/l, NR <50) and gastrin (42 pmol/l, NR <40) levels were detected. However, pancreatic CT showed no evidence of a tumour.

She was instituted on metyrapone and later ketoconazole. A simultaneous thymic resection and parathyroidectomy was performed. This did not cure her hyperparathyroidism, as corrected calcium levels were still elevated at 2.73-3.03 mmol/l. Cortisol levels were still elevated. Immunohistochemical studies of the tumour for ACTH were negative. She subsequently underwent a bilateral adrenalectomy with cure of her Cushing's syndrome: histological analysis showed diffuse and bilateral nodular hyperplasia of the adrenals.

In summary, we describe the novel case of a lady who presented with Cushing's syndrome due to bilateral nodular hyperplasia of the adrenals in association with MEN-1 and a thymic carcinoid tumour.