SUN-191 The Creatinine, the Crib and the Manometer - Navigating the Labyrinth of Primary Aldosteronism

A 21-year-old Ethiopian female with a five-year history of hypertension presented to medicine clinic with headaches and fatigue for two weeks. She was hypertensive to 163/113 mmHg. She had recently moved to the US and no prior medical records were available. She had been taking an unknown antihypertensive until three weeks prior. She was found to have a creatinine of 3.49 mg/dL. Renal ultrasound revealed bilateral, small echogenic kidneys without any evidence of renal artery stenosis. An intrauterine pregnancy was also incidentally discovered. Her aldosterone level was elevated to 486 ng/dL and her renin activity was 1.3 ng/ml/hr, with a ratio of 373, diagnostic of primary aldosteronism. Due to the markedly high ratio, a saline suppression test was deemed unnecessary for confirmation. Her serum potassium was normal at 3.6 mEq, likely due to poor renal clearance. Given renal failure, a CT non-contrast of the adrenal glands was performed with normal findings. She elected to terminate the high-risk pregnancy. Based upon her young age at presentation, family history of early onset hypertension, grossly elevated aldosterone: renin ratio and unrevealing workup for a primary tumor or hyperplastic adrenals, a diagnosis of familial hyperaldosteronism was considered. She failed a month-long trial of dexamethasone therapy, therefore glucocorticoid remediable aldosteronism was excluded. She was subsequently started on spironolactone with good response. Adrenal vein sampling was considered to find a surgical target for adrenalectomy but could not be performed given worsening kidney function. After discussion with Nephrology she opted for a pre-emptive renal transplant evaluation, rather than pursuing dialysis. Genetic testing for subclassification has been negative for mutations in KCNJ5 and CACNA1H with ongoing testing for novel mutations. Primary aldosteronism (PA) usually presents with recalcitrant hypertension, hypokalemia and an elevated aldosterone: renin ratio. It is commonly attributed to adrenal adenomas or hyperplasia with familial hyperaldosteronism (FH) remaining a rare etiology. FH is sub-divided into glucocorticoid remediable, type I, and non- glucocorticoid remediable, types II – IV. The initial diagnosis of such a condition during pregnancy and in the setting of worsening kidney disease presents a diagnostic and management challenge as this precludes adrenal vein sampling and contrast imaging. Our case highlights the importance of early screening for PA and illustrates the need for updated guidelines on aldosteronism workup in the setting of ESRD and pregnancy.