Laboratory challenges in primary aldosteronism screening and diagnosis

BACKGROUND AND OBJECTIVE: The laboratory has a critical role to play in the screening and diagnosis of primary aldosteronism. This review highlights some of the important analytical considerations and the new developments in the determination of aldosterone and renin. METHODS: The review considered the published literature and clinical practice guidelines in the area of primary aldosteronism. RESULTS: A brief introduction to primary aldosteronism is provided. A detailed description of the pre-analytical, analytical and post-analytical considerations for the laboratory determination of aldosterone, renin and the aldosterone to renin ratio follows. CONCLUSIONS: The lack of internationally accepted standardized methodologies and standard reference material has impeded screening and diagnosis of primary aldosteronism. The development of more accurate and sensitive methods by LC-MS/MS has improved the reliability of aldosterone and renin testing and the availability of commercial chemiluminescent assays may improve the standardization of reporting. Laboratorians need to understand the strengths and weaknesses of their analytical approach and ensure that their interpretative reports are appropriate to their assays.