title: Determination of urinary aldosterone using a plasma aldosterone 2D ID LC-MS/MS method.
abstract: OBJECTIVE
  In the diagnosis for primary aldosteronism, the measurement of urinary aldosterone is part of the confirmation test but diagnostic accuracy may be blunted due to poor immunoassay performance for urinary aldosterone. Nowadays, plasma aldosterone concentrations are measured preferably by LC-MS/MS yet such methods for urinary aldosterone are lacking.
  
  
  RESULTS
  We show that plasma and urinary aldosterone can be measured with the same 2D isotope dilution LC-MS/MS method. The accuracy of the method was tested against a certified reference material. The reference values for plasma and urinary aldosterone were established.
  
  
  CONCLUSIONS
  With this method, urinary aldosterone concentrations can be measured precisely, simply and accurately together with plasma samples with one set of calibration standards.
authors: Department of Clinical Chemistry, Laboratory of Endocrinology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors: Yasin
authors: Y
authors: Bekkach
authors: Department of Clinical Chemistry, Endocrine Laboratory, VU University Medical Center, De Boelelaan 1117, 1018 HV Amsterdam, The Netherlands.
authors: Annemieke C
authors: AC
authors: Heijboer
authors: Department of Clinical Chemistry, Laboratory of Endocrinology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors: Erik
authors: E
authors: Endert
authors: Department of Clinical Chemistry, Laboratory of Endocrinology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors: Mariëtte T
authors: MT
authors: Ackermans
mesh_terms: D000450:Aldosterone / Q000097:blood* / Q000652:urine*; D002138:Calibration; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D006929:Hyperaldosteronism / Q000097:blood / Q000652:urine; D057230:Limit of Detection; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000450:Aldosterone
keywords: 2D ID LC–MS/MS; hyperaldosteronism; plasma aldosterone; supported liquid extraction; urinary aldosterone