Assessing the utility of aldosterone suppression testing for primary aldosteronism: time to move forward

Dear Editors, We are happy to respond to Pamporaki and Stowasser and colleagues. Pamporaki et al. write to advocate that the saline suppression test remains a valuable confirmatory diagnostic tool for primary aldosteronism (PA), even though guidelines no longer recommend using this procedure for this purpose1 given the lack of supportive high quality evidence and poor diagnostic accuracy.1,2 By contrast, Stowasser et al. state that the main purpose of aldosterone suppression tests (AST) is to detect patients who have unilateral PA so that other patients may be spared adrenal venous sampling (AVS). Indeed, one of the reasons we undertook our study was to evaluate whether ASTs exhibited sufficient accuracy to serve this purpose. However, when evaluating patients who had undergone both the saline suppression test and captopril challenge test, we found poor concordance between these ASTs, suboptimal diagnostic accuracy for PA, and poor discriminatory capacity to predict lateralization and surgical outcomes.3