9B.06: COMPARISON BETWEEN XXXX AND @entity916 MEASUREMENT BY CHEMILUMINESCENT IMMUNOASSAY AND RADIOIMMUNOASSAY FOR THE DIAGNOSIS OF PRIMARY ALDOSTERONISM.

@entity1 @entity20805 @entity1369 @entity101 @entity916 @entity774
OBJECTIVE: Primary aldosteronism (PA) is the most frequent cause of secondary @entity101 responsible for an increased rate of cardiovascular events. According to the Endocrine Society Guidelines, up to 50% of @entity101 @entity1 should be screened for PA, using the @entity1369 to @entity916 (or plasma @entity916 activity, PRA) ratio (AARR and ARR, respectively). The automated Diasorin LIAISON   chemiluminescent immunoassay for @entity916 and @entity1369 measurement became available and in many laboratories is currently used instead of the classical radioimmunometric PRA and @entity1369 assay. Aim of the study was to prospectively compare the diagnostic accuracy of AARR and ARR as screening test for PA and the two @entity1369 assays also during confirmatory test in @entity1 with a positive screening test. DESIGN AND METHOD: One hundred @entity1 were screened for PA and 44 @entity1 underwent confirmatory test (either by intravenous saline load or by @entity20805 challenge test). We considered as cut off for the AARR 2.7(ng/dL/mU/L) and for the ARR 30(ng/dL/ng/mL/h). All @entity1 positive to one of the two screening test underwent confirmatory test; @entity1 with positive confirmatory test underwent subtype diagnosis by CT scanning and adrenal vein sampling. RESULTS: Seventy three @entity1 were diagnosed as essential @entity101 , 22 had @entity774 and 5 had an @entity1369 producing adenomas (APA). The AARR displayed a sensitivity of 78% and a specificity of 100%, whereas the ARR had a sensitivity of 96% and a specificity of 90%. Of the 6/27 PA @entity1 missed by AARR, none resulted to be affected by APA. All PA @entity1 were correctly diagnosed by chemiluminescence at confirmatory test. In the overall sample of 181 measurements available both the correlation for the PRA with @entity916 and for @entity1369 in chemiluminescence and radioimmunoassay were highly significant (Rho=0.66, p<0.0001 and Rho=0.80, p<0.0001, respectively). On ROC curves, the AUC for AARR was 0.905 (95% CI 0.821-0.988) and for ARR 0.947 (95% CI 0.903-0.991) and they were not significantly different. CONCLUSIONS: The automated @entity1369 and @entity916 chemiluminescent assay is a reliable alternative to the well-established radioimmunometric method, especially for the detection of APA.
