Endocrine Abstracts

A 49-year-old lady was referred by her GP with lethargy, oligomenorrhoea and persistent hypertension despite three anti-hypertensives (lisinopril, amlodipine, and atenolol). She denied exogenous steroid usage and had no other medical history.

On examination, she had features of Cushing’s syndrome including plethora, moon face, central obesity and androgenisation of her facial skin. She weighed 98 kg.

Overnight (1 mg) low dose dexamethasone suppression test disclosed no suppression of cortisol. High dose dexamethasone suppression test suggested pituitary-dependant Cushing’s. A confirmatory CRF test showed marked rise in serum cortisol and ACTH. MRI brain showed a 9 mm low signal area in the left side of pituitary post gadolinium in keeping with pituitary adenoma. Her pituitary profile was otherwise unremarkable.

She was referred for hypophysectomy. Four months later, on the day of surgery, her pre-operative MRI brain showed spontaneous shrinkage of her pituitary adenoma with no signs of haemorrhage to suggest apoplexy. Her surgery was cancelled.

Two months later, she had lost 8 kg in weight with a normalising body habitus and no proximal myopathy. Her repeat low dose dexamethasone suppression test was normal; CRF testing shows residual but much improved cortisol secretion 10 months later. Her static pituitary screen is otherwise normal and her weight loss continues. Repeat MRI pituitary showed a normal pituitary gland in August 2010.

This is the first case report which showed a near spontaneous resolution of pituitary Cushing’s disease without any medical or surgical intervention. Possible causes include spontaneous infarction of the tumour.