Primary aldosteronism - why is the diagnosis difficult?

Abstract

Primary hyperaldosteronism (PA) is a pathogenically heterogenous syndrome. It may be caused by: a) solitary or multiple adenomata or carcinoma of the adrenal glomerular zone, b) by unilateral or bilateral micro- or macromodular hyperplasia of this zone, c) by a genetic defect of steroidogenesis (famillial hyperaldosteronism type I and II) oraz d) by extraadrenal aldosterone synthesis (paraendocrinopathy). The classical signs and symptoms of PA (aterial hypertension, hypokaliemia caused by incressive renal K excretion, hypokalemic alkalosis, clinical symptoms of K depletion) are found only in 20–40% of patients with PA predominantly in those with solitary adenoma of the adrenal glomerular zone. In these patients almost always autonomous hypersecretion of aldosterone may be found, while in the other pathological forms of PA this is not always the case. Routine estimation of plasma renin activity or renin concentration respectively and of the aldosterone-renin ratio (ARR) significantly increased the frequency of PA diagnosis in normokalemic hypertensive patients. In patients with monogenic forms of low-renin hypertension and of so-called low-renin essential hypertension performance of genetic examinations are often necessary. The question, is there an epidemic of primary aldosteronism which needs elaboration of new diagnostic and therapeutic strategies in hypertensive patients - is subject of continual controversy.