Biomarkers for the diagnosis of acute kidney injury.
OBJECTIVE
The identification of acute kidney injury relies on tests like blood urea nitrogen and serum creatinine that were identified and incorporated into clinical practice several decades ago. This review summarizes clinical studies of newer biomarkers that may permit earlier and more accurate identification of acute kidney injury.


RESULTS
The urine may contain sensitive and specific markers of kidney injury that are present due to either impaired tubular reabsorption and catabolism of filtered molecules or release of tubular cell proteins in response to ischemic or nephrotoxic injury. Many potential markers have been studied. Promising injury markers in the urine include N-acetyl-beta-D-glucosaminidase, neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, and interleukin-18. Serum cystatin C may be a better measure of glomerular filtration rate than serum creatinine or blood urea nitrogen.


CONCLUSIONS
New biomarkers of kidney injury and glomerular filtration rate hold the promise of substantially improving the diagnostic approach to acute kidney injury. Adequately powered clinical studies of multiple biomarkers are needed to qualify the biomarkers before they can be fully adopted in clinical practice. Once adopted, more sensitive biomarkers of acute kidney injury hold the potential to transform the care of patients with renal disease.
Waikar
Sushrut S
SS
Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA. swaikar@partners.org
Bonventre
Joseph V
JV
D058186:Acute Kidney Injury / Q000175:diagnosis*; D015415:Biomarkers / Q000032:analysis*; D006801:Humans; D007677:Kidney Function Tests
D015415:Biomarkers