Endocrine Abstracts

JOINT1355

Primary Aldosteronism (PA) is the most common cause of secondary hypertension and is associated with long term morbidity and organ dysfunction including chronic kidney disease (CKD). Optimal management for unilateral PA is adrenalectomy however development of post-operative hypoaldosteronism with resultant hyperkalaemia is increasingly being recognised as a complication. We present a patient with delayed diagnosis PA, established CKD and recovery complicated by hypoaldosteronism. We review the literature regarding the risk factors for and management of post-operative hypoaldosteronism, and present local data on post-operative hyperkalaemia rates. We describe a 60-year-old man who underwent unilateral adrenalectomy after 10 years of refractory hypertension. At time of surgery, he had established stage G3aA2 CKD, type 2 diabetes mellitus and ischaemic heart disease. Two weeks after surgery, the patient was admitted to hospital with severe hyperkalaemia, that was initially resistant to standard treatment measures. His hyperkalaemia resolved after initiation of Fludrocortisone and Sodium Bicarbonate. Post operative hyperkalaemia has been described in between 3-48% of patients undergoing unilateral adrenalectomy and attributed to transient, but sometimes prolonged, hypoaldosteronism. Most cases of hyperkalaemia are reported to occur within one to three weeks of surgery, however reports of up to 6 months post operatively have been described. This is likely a consequence of prolonged renal exposure to aldosterone excess, resulting in chronic suppression of renin with subsequent atrophy and suppression of the contralateral zona glomerulosa cells. In our hospital, between 2010 - 2020, 23 patients underwent unilateral adrenalectomy. Eight patients (34.8%) experienced transient hyperkalaemia; however, no cases of prolonged hyperkalaemia were recorded. Only 39.1% of patients had potassium levels monitored beyond 28 days, and 21.7% has levels monitored for less than 14 days. Hyperkalaemia can be severe and associated with life threatening cardiac arrhythmias. Despite this, there are not clear consensus guidelines on strategies to predict, prevent or monitor for this. Suggested risk factors include age >50 years, duration of hypertension >10 years, established CKD, adrenal adenoma >2 cm and male gender. As patients with established complications of hypertension may be both more at risk of complications, and less likely to derive benefit from surgery, this case highlights some considerations and complexities of patient selection for surgical management of PA. This case provides strength to recommendations to recognise and treat PA early, and to develop robust protocols for post-operative electrolyte surveillance, treatment and management of anti-hypertensives in the peri-operative setting.