Diagnosis of Acute Kidney Injury in Neonates: Can Urinary Biomarkers Help?

Abstract

Diagnosing acute kidney injury (AKI) in a diverse population of newborns is challenging. Current definitions of AKI focus on changes in serum creatinine and urine output both of which are subject to maturational and physiological change in newborn populations. Changes in serum creatinine reflect a significant loss of renal function and are a late marker of AKI. This article summarises the current literature related to the use of urinary biomarkers for diagnosing AKI in newborn populations. There is a growing body of evidence that supports the use of novel urinary biomarkers for both diagnosing and predicting the occurrence of neonatal AKI. The possibility of an earlier, pre-clinical diagnosis of kidney damage affords opportunities for researchers and clinicians to develop strategies aimed at reducing the severity of kidney injury. Future definitions of AKI will likely incorporate these non-invasive and early markers of kidney injury as either adjuncts or alternatives to measures of the change in kidney function (i.e. serum creatinine). Further research needs to demonstrate a relationship between AKI diagnosed using novel biomarkers and important long-term adverse clinical outcomes such as hypertension and/or chronic kidney disease. In addition, studies which use urine biomarkers criteria to enrol infants that show improved process of care or important clinical outcomes will be needed before they are adapted into clinical care.