Figure 3.

Patient-specific discordance of immunoassay versus LC-MS/MS measurements of aldosterone according to 4 or more measurements of plasma aldosterone in each of 48 patients, including 24 in whom measurements included the Liaison immunoassay (A) and 24 for the iSYS immunoassay (B). Discordance in y-axes is represented by fold differences in immunoassay over LC-MS/MS measured concentrations of aldosterone. The 4 or more separate measurements for each patient are from peripheral blood samples taken at screening, before and during the SIT, and during AVS for some patients who progressed to that procedure. Different symbols for the differences are according to whether LC-MS/MS measured aldosterone concentrations were below (■) or above (●) 170 pmol/L and serve to illustrate contributions of lower plasma aldosterone concentrations to measured differences for the Liaison and not the iSYS immunoassay.