Endocrine Abstracts

A 56-year-old man of Ghanian descent was referred to the endocrine clinic with a 16-year history of drug resistant hypertension. His past medical history was of hypertrophic cardiomyopathy, chronic kidney disease, and horseshoe kidney. He is one of seven hypertensive siblings, two of whom died of complications of hypertension. An incidental finding of bilateral adrenal nodules was noted on abdominal computed tomography. Plasma aldosterone concentration (PAC) was 1020 pmol/l, plasma renin activity (PRA) 1.3 nmol/l/hr, and aldosterone/renin ratio was 785, with creatinine 143 µmol/l and normokalaemia. At his first endocrine clinic appointment, blood pressure (BP) was 170/90 mmHg on spironolactone 100 mg, lisinopril 20 mg, indapamide 1.5 mg, moxonidine 200 mg, doxazosin 16 mg twice daily, and verapamil 240 mg twice daily. A diagnosis of primary aldosteronism (PA) was confirmed by the captopril challenge test. At baseline, PRA was 1.0 nmol/l/hr, PAC 544 pmol/l, and creatinine 186 µmol/l. At 120 minutes from captopril administration, PRA was 0.5 nmol/l/hr and PAC was 528 pmol/l. He was considered for inclusion in PA research studies. Adrenal vein sampling (AVS) was then performed with cosyntropin stimulation.Selectivity index (ratio of cortisol in the adrenal vein to low IVC) was 16.9 on the right and 10.9 on the left, confirming successful cannulation of both adrenal veins. Aldosterone to cortisol ratio was 1.39 on the right and 1.13 on the left, with a lateralization index (LI) of 1.23. This demonstrated bilateral aldosterone secretion, precluding surgical intervention or enrolment onto the MATCH (Wu et al., 2023) or FABULAS (Argentesi et al., 2023) studies. He was managed medically with spironolactone 25 mg, amlodipine 10 mg, doxazosin 8 mg twice daily, and sotalol 160 mg twice daily, achieving a BP control of 132/84 mmHg without postural hypotension. He remains on review in the endocrine clinic. This case of a 16-year-long delay in diagnosis and, consequently, appropriate medical management, illustrates the need for improved awareness of PA amongst clinicians, simplification of the diagnostic pathway, and effective medical strategies for managing PA.