Diagnosis and Assessment
A. Primary aldosteronism: screening and diagnosis Recommendations
Screening for primary aldosteronism should be considered in hypertensive patients with the following (Grade D):
- Unexplained spontaneous hypokalemia (Kþ < 3.5 mmol/L) or marked diuretic-induced hypokalemia (Kþ < 3.0 mmol/L);
- Resistance to treatment with 3 drugs;
- An incidental adrenal adenoma.
- Screening for primary aldosteronism should include assessment of plasma aldosterone and plasma renin activity or plasma renin (Table 13).
- For patients with suspected primary aldosteronism (on the basis of the screening test; Table 13, section II), a diagnosis of primary aldosteronism should be established by demonstrating inappropriate autonomous hypersecretion of aldosterone using at least 1 of the manoeuvres listed in Table 13, section III. When the diagnosis is established, the abnormality should be localized using any of the tests described in Table 13, section IV.
- In patients with primary aldosteronism and a definite ad-renal mass who are eligible for surgery, adrenal venous sampling is recommended to assess for lateralization of aldosterone hypersecretion. Adrenal vein sampling should be performed exclusively by experienced teams working in specialized centres (Grade C).
- If pheochromocytoma or paraganglioma is strongly suspected, the patient should be referred to a specialized hypertension centre, particularly if biochemical screening tests (Table 14) have already been shown to be positive (Grade D).
- The following patients should be considered for screening for pheochromocytoma or paraganglioma (Grade D):
- Patients with paroxysmal, unexplained, labile, and/or severe (BP 180/110 mm Hg) sustained hypertension refractory to usual antihypertensive therapy;
- Patients with hypertension and multiple symptoms suggestive of catecholamine excess (eg, headaches, palpitations, sweating, panic attacks, and pallor);
- Patients with hypertension triggered by b-blockers, monoamine oxidase inhibitors, micturition, changes in abdominal pressure, surgery, or anaesthesia;
- Patients with an incidentally discovered adrenal mass;
- Patients with a predisposition to hereditary causes (eg, multiple endocrine neoplasia 2A or 2B, von Reck-linghausen neurofibromatosis type 1, or Von Hippel-Lindau disease);
- For patients with positive biochemical screening tests, localization of pheochromocytomas or paragangliomas magnetic resonance imaging (preferable), computed to-mography (if magnetic resonance imaging unavailable), and/or iodine I-131 meta-iodobenzylguanidine scintig-raphy should be used (Grade C for each modality).