Supramaximal elevation in B-type natriuretic peptide and its N-terminal fragment levels in anephric patients with heart failure: a case series

Table 4 Cut-off values of B-type natriuretic peptide (BNP) and N-terminal fragment (NT-proBNP) as diagnostic tests to 'rule out' and 'rule-in' congestive heart failure (CHF) ^§

‘Rule out' CHF	‘Rule in' CHF
BNP cut-off values to 'rule out' CHF: <100ng/L.	BNP cut-off values to 'rule in' CHF: >400ng/L.
When stratified for GFR,
GFR >90mL/minute: <71ng/L.
GFR >60–89mL/minute: <104ng/L.
GFR >30–59mL/minute: <201ng/L.
GFR <30mL/minute: <225ng/L.
NT-proBNP cut-off value to 'rule out' CHF: <300ng/L.	NT-proBNP cut-off value to 'rule in' CHF.
	When stratified for age, When stratified for GFR,
	Age <50 year: >450ng/L. GFR >60mL/minute: >900ng/L.
	Age 50–75 year: >900ng/L. GFR <60mL/minute: >1200ng/L.
	Age >75 year: >1800ng/L.

^§Reflects a nomogram version of Bayes' Theorem, in diagnosis-uncertain patients (pre-test probabilities of ~50%), a likelihood ratio for a positive test result ≥10 is required to 'rule in' disease with reasonable certainty (post-test probability ≥90%) where a positive test result = (sensitivity) / (1 – specificity) = true positives / false positives ratio; whereas likelihood ratio for a negative test result ≤0·10 is required to 'rule out' disease with reasonable certainty (post-test probability ≤10%) where a negative test result = (1 – sensitivity) / (specificity) = false negatives / true negatives ratio).
CHF; Congestive heart failure, BNP; B-type natriuretic peptide, GFR; Glomerular filtration rate, NT-proBNP; N-terminal fragment.

ISSN: 1752-1947