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Two serious analytical problems with B-Type Natriuretic Peptide (BNP)
determining are discuted in professional literature:
First, the high intraindividual biological variation hamper interpretation
of changes in BNP concentrations and may partly explain his poor
diagnostic value in chronic heart failure. The value of BNP for follow-up
and treatment optimization, and for prognosis determining, remains largely
to be established (1).
Second, diagnostic accuracy, and prognosis determining, too, can strongly
depend on patient selection and on the cardiac natriuretic peptide assayed
(BNP, N-terminal pro-A-type natruretic peptide, or NT-proBNP), as well as
on the analytical performance and diagnostic accuracy of the immunoassay
Analytic bias caused by assay differences and reagent variations can cause
major problems for clinicians trying to interpret the test results.
There's no other alternative, better assy harmonisation could improve
practice and simplify the problems of having each local laboratory
responsible for establishing their own reference intervals and medical
1. Bruins S, Fokkema MR, Romer JWP, DeJongste MJL, van der Dijst FPL,
van den Ouweland JMW, Muskiet FAJ. High intraindividual variation of B-
type natriuretic peptide (BNP) and Amino-terminal proBNP in patients with
stable chronic heart failure. Clin Chem 2004;50:2052-2058.
2. Clerico A, Prontera C, Emdin M, Passino C, Storti S, Poletti R et al.
Analytical performance and diagnostic accuracy of immunometric assys for
the measurement of plasma B-type natriuretic peptide (BNP) and N-terminal
proBNP. Clin Chem 2005;51:445-447.
No competing interests
19 March 2005
Health Insurance Company, Murgasova 3, SK-043 25 Kosice, Slovakia