BNP and a renal patient: emphasis on the unique characteristics of B-type natriuretic peptide in end-stage kidney disease.

BACKGROUND: The widespread use of brain natriuretic peptide testing among patients with end-stage kidney disease (ESKD) has brought new insight to prognostic cardiovascular factors in this population, but has also raised questions regarding the diagnostic potential of B-type natriuretic peptide (BNP) and NT-proBNP in subjects with renal impairment.

METHODS: Highlighting the most important recent observations in the field, this review discusses the unique characteristics of BNP testing and interpretation in chronic kidney disease.

RESULTS: We review in detail the physiology and effects of BNP along with providing a thoughtful analysis of the limitations of BNP testing in patients with impaired kidney function. Additionally, the practicability of BNP in the management of renal patients with some rational suggestions for the use of BNP are presented.

CONCLUSION: Although at present the use and interpretation of BNP testing in ESKD patients is complicated by altered renal clearance and frequent cardiac co-morbidity and, moreover, the complex and in many parts unknown interplay between the heart and the kidneys (cardiorenal syndrome), the prognostic value of elevated BNP is validated in the ESKD population. The importance of improving our understanding of the mechanisms of biomarkers in heart-kidney interdependence is emphasized.