Purpose of review: Acute renal disease has major prognostic impact in hospitalized patients. Early diagnosis using renal function markers such as serum creatinine or urinary output and effective treatment are currently not possible. This review focuses on recent studies examining the biological characteristics and the diagnostic and prognostic value of a novel biomarker, neutrophil gelatinase-associated lipocalin (NGAL), in patients at risk for acute renal disease.
Recent findings: NGAL levels increase early and proportional to the degree of renal injury in the urine and plasma. Here, we report the results of clinical studies where NGAL was measured in 325 patients with autoimmune and infectious diseases, those with cisplatin-associated nephrotoxicity, and more than 4000 patients at risk of acute kidney injury due to sepsis, cardiac surgery, exposure to contrast media, or after renal transplantation. Whenever renal damage occurred, as evidenced by histopathology or subsequent increase in serum creatinine levels, NGAL levels were higher than in patients without acute renal disease. An increase in NGAL substantially preceded clinical diagnosis of acute renal disease.
Summary: NGAL fulfills many characteristics of an appropriate 'real-time' renal biomarker. The data on NGAL could justify re-assessment of the concept and definition of acute kidney injury.