Endocrine Abstracts

66 year old man who had hypertension treated with Amlodipine 5 mg, Perindopril 10 mg, Nebivolol 5 mg, Doxazosin 8 mg and a Thiazide diuretic from the age of 45 with previous history of subarachnoid haemorrhage and DVT presented to emergency department with episode of weakness, nausea and dizziness. His serum potassium at initial presentation was 2.3 mmol/l. After stopping thiazide diuretic and beta blocker for 4 weeks and being commenced on Amlodipine 5 mg, Doxazosin XL 12 mg for BP control his potassium was 3.1, plasma aldosterone was 1497 pmol/l (194-970 pmol/l with plasma Renin activity of 1.0 ng/ml/h (1.0–4.2), giving an ARR of 1497. Saline suppression test showed a baseline aldosterone of 2099 pmol/l with undetectable plasma Renin activity and following saline suppression his aldosterone suppressed to 548 pmol/l. His morning cortisol was undetectable post 1 mg overnight Dexamethasone. His initial CT adrenal showed a 7-mm left sided adrenal adenoma with normal MRI adrenals. Subsequently, he went for adrenal vein sampling but unfortunately the radiologist was unable to cannulate right adrenal vein. He was referred to Addenbrooke’s Hospital, Cambridge for a 11C –metomidate PET–CT scan of adrenals that showed 12 mm nodule in right adrenal gland. He went for a right adrenalectomy based on 11C-metomidate PET–CT scan finding. He had an uncomplicated right laproscopic adrenalectomy. Two days post operatively he complained of profound tiredness and his morning cortisol came back as 24 nmol/l. His Bisoprolol, Doxazocin and eplerenone were stopped and he has remained on Amlodipine 5 mg and his blood pressure remained stable. His sodium was 136 mmol/l and potassium was 4.0 mmol/l. He was covered with steroids and a short synacthen test done 5 days post operatively that showed 0 min value cortisol of 217 nmol/l and 30 mins value 617 nmol/l. Based on this result his steroids were stopped. He was seen in clinic 5 weeks post surgery, he was well with a blood pressure remained stable of 130/72 on Amlodipine 5 g and Bisoprolol, 2.5 mg. Serum potassium was 4.7 mmol/l.

Learning points:

1) Investigation of mineralocorticoid hypertension

2) What to do when your radiologist fails to cannulate both adrenal veins

3) Did this patient have ‘Connshings’ syndrome given the recent data and low cortisol post operatively