Aldosterone-producing adenoma without hypertension: a report of two cases

Normotensive primary hyperaldosteronism is exceedingly rare. We report two new cases of this syndrome in two middle-aged women, one of Asian origin. T he presenting signs were tetany in one case and an adrenal mass in the othe r, Neither patient had hypertension, despite repeated measurements with a m anual armlet. A typical biological profile of primary hyperaldosteronism wa s demonstrated in both patients, including hypokalemia with inappropriate k aliuresis, elevated resting plasma aldosterone, and undetectable plasma ren in activity. The circadian rhythm of blood pressure was studied by ambulato ry monitoring pre- and post-operatively. It confirmed the lack of hypertens ion, but the circadian rhythm of blood pressure was lost before surgery in one patient. Surgical removal of the histologically typical aldosterone-pro ducing adenomas normalized the kalemia. The main finding in these two patie nts was spontaneously low blood pressure in the post-operative period, This suggests that excess aldosterone induced relative hypertension in these pa tients whose blood pressure was spontaneously very low. Genetic screening f or dexamethasone-sensitive hyper aldosteronism was negative in both patient s.