Endocrine Abstracts

Introduction: Primary hyperaldosteronism (PA) is a disturbance caused by the autonomous production of aldosterone by the adrenal gland. The most frequent causes are due to bilateral supra-renal gland hyperplasia and aldesterone producing adenoma. It is most frequent amongst women aged between 30 and 50 years of age. It is clinically characterised by hypertension (HTN), resistant to therapy. Hypokalaemia, which is known as a ‘classical marker’ is found in less than a third of the patient and is followed by inespecific symptoms (muscle pain/weakness, polydipsy, polyuria, nocturia and parathesia). Diabetes mellitus (DM) can also be found in some cases.

Clinical case: A 55-year-old woman referred from internal medicine due to a adenoma on her right supra-renal gland with hypertension and hypokalaemia. The patient has been hypertensive for the past 16 years with the hypertension being resistant to therapy despite being on four antihypertensives (loasatran/hydrochlorothiazide 100 mg/25 mg, carvedilol 25 mg and spironolactone 50 mg). All tests were normal, except a high aldosterone/renin ratio (17.86). The patient was also diagnosed with DM and started on metformin. She was also given KCl for her hypokalaemia. A salt-loading test was carried out that confirmed the diagnosis of HP. (aldosterone 0–35.94; 4 h 56.18 ng/dl). The patient was subjected to a right sided adrenalectomy without complications leading to normokalaemia 48 h after surgery. The aldosterone/renin ratio also normalised. The patient is now able to maintain a normokalaemic state and she only needs 10 mg/day of lercanidipine to control her blood pressure.

Discussion: Due to the resistant hypertension before the age of 40 and the lack of experience with or unsatisfactory results obtained by catheterising supra-renal veins the surgical option was chosen in this case. We would like to highlight the importance of monitoring potassium levels on a weekly basis during the first month post-surgery due to the risk of transient hipoaldosteronism. With this patient we noticed an improvement in the blood pressure profile during the first month after the surgery. As described in the literature, an improvement or normalisation of hypertension can happen 1–6 months post surgery. However, due to the patient’s long standing hypertension it is unlikely that this will normalise.