[Primary hyperaldosteronism: difficulties in diagnosis]

Primary hyperaldosteronism (PA) - is the clinical syndrome, results from autonomous of the major regulators of secretion, aldosterone overproduction by a tumorous or hyperplastic tissue in adrenal cortex. Being the most frequent cause of secondary hypertension, PA may be represented by disorders with unilateral or bilateral aldosterone overproduction and differential diagnosis between them is crucial for choosing a right therapeutic approache: lifelong medical therapy with mineralocorticoid receptor antagonists or unilateral adrenalectomy. Adrenal venous sampling (AVS) is currently the «gold standard» test for identifying laterality of excess hormone production, unlike imaging tests, sensitivity and specificity of which is not enough, due to inability to evaluate functional activity with confidence, and also to limitations in detecting tiny abnormalities of adrenals, such as microadenoma or hyperplasia. Excluding certain cases, AVS is recommended to patients with confirmed PA, planning surgical treatment, to determine the lateralization of aldosterone hypersecretion. Described clinical case of patient with confirmed lateralization from adrenal without any detected lesions on CT-imaging and nonfunctioning tumour on contralateral side, highlights the importance of using AVS for decision to refer patients for surgery.