Confirmatory Testing for Primary Aldosteronism

How to Escape from Primary Aldosteronism? News and Views on an Adrenal Disorder of Salt Retention

“…Other reasons may include the wide and changing landscape of assays and the problem that published cut-off values are readily adopted by laboratories although there is a substantial inter-assay variation [26]. Recent papers have put a main focus on testing in primary aldosteronism and addressed these and other aspects [3,23,[27][28][29][30][31][32][33] and proposed ideas for possible solutions [34]. Ideally, antihypertensive medication should be switched to verapamil slow-release, hydralazine, prazosin, doxazosin, and terazosin [3].…”

“…Despite the fact that the outcome of a confirmation test may also be hampered by a number of uncertainties, each suspected case should undergo a confirmation test although the sensitivities and specificities range between 75 and 95 % for some tests only and do not necessarily exceed the accuracy rates of screening tests [3,55]. While these tests are described in detail elsewhere [3,30,33], some advantages and disadvantages of tests are discussed below. For additional information, see ▶table 2.…”

“…The Brisbane and the Munich groups see a benefit from performing this test in sitting position, others combine it with a low-dose dexamethasone suppression test (▶table 2) [58,59]. Further discussion can be found elsewhere [30,33,34]. The great advantage of aldosterone measurements in 24-h urine samples after oral sodium loading is that it can be easily combined with the determination of cortisol (and profiling of other steroids) and (nor)metanephrine during the investigation for secondary hypertension or an adrenal mass and even assessment of sodium excretion, creatinine clearance and albuminuria in an outpatient setting.…”

“…As the ARR is more specific when elevated despite ACE-inhibitor or AT1R-blocker therapy, the informative value of the ARR and blood aldosterone concentration after a captopril (CCT) or a losartan challenge (LCT) test reaches the standard of a confirmation test (▶table 2) [3,4,30]. There are, however, various test modifications and different assay methodology because of which it is recommended to analyze own experience.…”