Endocrine Abstracts

We present a case of Phaeochromocytoma co-secreting ACTH as a rare cause of Cushing’s syndrome. Our patient is a 49 year lady admitted acutely with sudden onset headache and severe hypertension. CT brain and CSF analysis were normal. Her urinary catecholamines were found to be elevated. Noradrenaline 709 and 972 nmol/ mmol of creatinine (ref range 0–48), Adrenaline 215 and 256 (ref range 0–10). CT abdomen revealed 4.2 cm left adrenal mass, MIBG scan confirmed phaeochromocytoma. Initial treatment involved alpha and beta blockade with dose titration, reaching up to phenoxybenzamine 70 mg three times daily and propranolol LA 160 mg. Despite this she remained haemodynamically unstable and clinically started to become cushingoid. Investigations for cortisol excess revealed ectopic ACTH secretion. Cortisol following 1mg dexamethasone suppression test was >1750 nmol/L, 24 hr urine free cortisol >1750 nmol/L and ACTH 555 ng/L. Metyrapone was added to her treatment and was transferred to tertiary centre for adrenalectomy. Her pre-op course was complicated by admission to ITU for suspected respiratory failure due to swine flu associated pneumonia and a small pulmonary embolus. After recovery, she successfully underwent laparoscopic left adrenalectomy. Subsequent biochemical testing and imaging confirmed complete resolution of catecholamine and cortisol excess. Screening for MEN was negative. This case is unusual in its acute presentation with highly metabolically active phaeochromocytoma which has probably masked the symptoms and signs of cortisol excess until active blockade of catecholamine action.

Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.