test directorySearch Results
Click here to search again.
Test Name:
B-Type Natriuretic Peptide
- SBMF No:
23176 - Performance Lab Name:
Immunology - Test Mnemonic:
BNP-TRIAGE - ABN:
May be required – Medical Necessity - CPT Code:
83880 - LOINC Code:
42637-9 - Also Known As:
BNP
Brain Type Natriuretic Polypeptide - Spec Type:
Whole blood - Spec Container:
Lavender top (EDTA) tube - Pref Vol:
1.0 mL - Min Vol:
0.3 mL - Fasting:
No - Spec Collect:
Routine venipuncture - Spec Process:
Do not centrifuge
Maintain as whole blood if specimen will be tested within 24 hours
If specimen will not be tested within 24 hours:
- Within 4 hours of collection, centrifuge
- Transfer plasma to separate plastic tube
- Freeze and transport frozen - Spec Store Transport:
Whole Blood: Room temperature or refrigerated
Plasma: Frozen - Spec Stability:
24 hours room temperature (20-30°C) or refrigerated (2-8°C)
If will not be tested within 24 hours of collection: centrifuge within 4 hours of collection, transfer plasma to separate plastic tube, and freeze - Methodology:
Fluorescent Enzyme Immunoassay (FEIA) - Use:
Of use in the diagnosis of early-stage congestive heart failure (CHF) - Clinical Significance:
In response to a rise in blood pressure, the heart releases two peptides. Of the two, brain-type natriuretic peptide (BNP) is the cardiac hormone that is released from the ventricles. It derives its name from the fact that it was first discovered in brain tissue. BNP lowers blood pressure by: 1) relaxing arterioles, 2) inhibiting the secretion of renin and aldosterone, and 3) inhibiting the reabsorption of sodium ions by the kidneys. The latter two effects reduce the reabsorption of water by the kidneys. The volume of urine increases, as does the amount of sodium excreted in it. These effects give BNP its name (natrium = sodium; uresis = urinate). The net effect of these actions is to reduce blood pressure by reducing the volume of blood in the circulatory system. BNP is part of a system regulating blood pressure and fluid balance. It is continuously released from the heart in response to both ventricular volume expansion and pressure overload. Diagnosing congestive heart failure (CHF) in very early stages permits early interventions that might prevent the disease from advancing.Various studies have demonstrated that circulating BNP concentrations increase with the severity of CHF based on the NYHA classification. There is a positive correlation between blood BNP concentrations and left ventricular end diastolic pressure and inverse correlation to left ventricular function. Thus, BNP provides an independent assessment of left ventricular function without the use of other invasive or expensive diagnostic tests.BNP concentration in control Non-CHF population increases with age, with a mean of 13.9 at age 45 and 63.7 at age 75. Females have higher concentrations than males. The percentage of patients in each NYHA functional class having levels greater than 100 pg/mL. - Reference Range:
0-100 pg/mL
The recommended decision threshold is 100 pg/mL in patients age 55 and older, which gives an overall general specificity of greater than 98%. However, the specificity and sensitivity of the test varies in different age groups and sexes. - Day Run:
Mon-Sat - Time Run:
If received by 7:00 am - Time Reported:
Reported by 5:00 pm same day - Test Type:
ENZYME CARDIAC
