Comparison of Abbott AxSYM and Roche Elecsys 2010 for measurement of BNP and NT-proBNP.
BACKGROUND
B-type natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are small cardiac hormones released from the heart. They can be used as an important aid to diagnose congestive heart failure (CHF).


METHODS
We compared the performances of the Abbott AxSYM and Roche Elecsys 2010 for the measurement of BNP and NT-proBNP. The first method uses a microparticle enzyme-linked immunoassay, whereas the other uses chemiluminescent immunometric assay.


RESULTS
The CVs using pooled sera ranged from 3.7% to 12.7% for the AxSYM and 0.9% to 2.2% for the Elecsys 2010. The Passing and Bablok regression was Elecsys 2010 NT-proBNP=7.23xAxSYM BNP+2.53. The BNP in EDTA plasma was more stable than in serum. The immunoreactivity difference of NT-proBNP in serum or EDTA plasma was within 10% when stored at 4 degrees Celsius or 25 degrees Celsius for 72 h. Receiver operating characteristic (ROC) curves were different for both assays, and the areas under the curves were 0.704 and 0.841 for the AxSYM and Elecsys 2010 method, respectively.


CONCLUSIONS
Both assays were not entirely specific for heart failure. The precision and stability for NT-proBNP was better than for BNP in serum. It is important to use method-appropriate reference ranges (or cutoff) for the BNP and NT-proBNP, respectively, in the assessment of CHF.
Chien
Tzu-I
TI
Department of Laboratory Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Chen
Hui-Hou
HH
Kao
Jau-Tsuen
JT
D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D008163:Luminescent Measurements; D020097:Natriuretic Peptide, Brain / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis*; D012372:ROC Curve; D012680:Sensitivity and Specificity
D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain