[Two case reports on resistant hypertension].

Primary aldosteronism (PA) is a frequent cause of resistant hypertension. The clinical presentation is heterogeneous, but a suppressed or low normal renin (especially with ACE inhibitors or sartans) should raise suspicion for primary aldosteronism, even when aldosterone levels are in the normal range. Diagnosis of unilateral hormone production from an adrenal adenoma (Conn syndrome), which is curable by surgery, requires adrenal vein sampling, which should be performed in experienced centers.