Endocrine Abstracts

Background: Adrenal incidentalomas are classified as adrenal lesions picked up on imaging performed due to reasons other than to look at the adrenals. With cross sectional imaging becoming more frequent, the frequency of adrenal lesions being detected and referred to endocrine services is increasing and dedicated adrenal incidentaloma clinics are being set up to screen these patients for potential pathology.

Case: We present a 63 year old lady who underwent a CT colonogram due to change in her bowel habit. This picked up a 14 mm bulky left adrenal gland, described as an adenoma, and prompted referral to the nurse led, adrenal incidentaloma clinic. She had type 2 diabetes and was on 3 antihypertensives. On questioning, she complained of abdominal obesity and thin limbs with proximal myopathy. Initial screening biochemistry was requested. This showed raised urinary free cortisol (UFC) of 1136 nmol/24 hr, with post overnight dexamethasone test cortisol of 427 nmol/L. An MRI of her adrenals showed bilateral lipid rich nodules consistent with small adenomas. Hypercortisolaemia was confirmed on second UFC and her cortisol did not suppress on the low dose dexamethasone suppression test. A CRH test showed an exaggerated ACTH response adding evidence for pituitary driven Cushing’s syndrome. A pituitary MRI was subsequently arranged which showed a 14 mm hypoenhancing pituitary lesion. She has been discussed in our regional pituitary MDT and has now been listed for a trans-spenoidal hypophysectomy.

Discussion: Adrenal incidentalomas are a common finding and, although the majority of these patients have benign lesions, a proportion of patients do have functioning adrenal adenomas requiring intervention. Incidental adrenal lesions leading to functional pituitary adenomas being detected are less common, as in this case. Therefore appropriate, thorough testing of adrenal incidentalomas is required to ensure pathologies are not missed and this can be done through structured adrenal incidentaloma clinics.