Endocrine Abstracts

Background: A 59 year old man was referred to Endocrinology from Neurology with a 2 year history of hypertension, and a 1 year history of mild hypernatraemia (146–148 mmol/l) and hypokalaemia (3.2–3.4 mmol/l). He had a past history of a cerebral aneurysm and superficial siderosis. His main complaints were severe fatigue, poor balance and tinnitus. His medications at diagnosis were Amlodipine 5 mg and Sertraline 50 mg.

Investigations: Blood pressure at his first attendance to the Endocrine Unit was 150/87. Aldosterone level was raised at 834 pmol/l with a suppressed renin <5 mIU/l. A saline infusion test failed to adequately suppress aldosterone levels (932–628 pmol/l). A 24 hour urine free cortisol was normal at 112 nmol/24 hours. A CT of the adrenal glands showed a 25×18 mm fatty nodule (Hounsfield units −5) within the left adrenal gland. The patient was referred for and underwent adrenal vein sampling however this was unsuccessful as the levels from both samples were the same as in peripheral serum, therefore it is likely that the adrenal veins were unsuccessfully cannulated.

Progress: Antihypertensive medication was changed to Spironolactone 50 mg and titrated up to 100 mg. His blood pressure at the last clinic visit was 147/68 and potassium level was 4.0. Nine months after commencing spironolactone he had developed gynaecomastia, 3–4 cm bilaterally. If this persisted or progressed, other medical options such as Epleronone or Amiloride were to be considered.

Discussion points: This case illustrates the workup of a patient with primary hyperaldosteronism and the challenges of decision making when adrenal vein sampling is inconclusive. Newer imaging modalities show potential but are not widely available. Should surgery be considered in the absence of confirmatory AVS in view of the adrenal nodule and side effects with Spironolactone? What is the audience’s experience with second line medical agents?