Serum neutrophil gelatinase-associated lipocalin - a sensitive novel marker of renal impairment in liver cirrhosis?

Recently, neutrophil gelatinase-associated lipocalin (NGAL) has been introduced as a sensitive and early marker of acute kidney injury [5] . NGAL in cirrhosis and chronic renal failure has not been investigated so far. We have therefore analyzed NGAL and GFR in patients with Dear Sir, Renal dysfunction is a frequent and clinically relevant problem in patients with cirrhosis of the liver [1] . While acute renal failure as in hepatorenal syndrome type 1 is characterized by a rapid increase of serum creatinine (Crea) concentration [2] , chronic renal dysfunction may be difficult to detect. For determination of the glomerular filtration rate (GFR), the use of clearance techniques is the gold standard. These techniques, however, are cumbersome and not suitable for clinical routine. Serum Crea is simple and easy to determine and therefore widely used per se or in Crea-based formulae such as MDRD (Modification of Diet in Renal Disease formula, using serum Crea, age and gender). Unfortunately, Crea is not a precise parameter of renal function in cirrhosis [3] . The overestimation of GFR by serum Crea and Crea-based equations is striking, particularly in decompensated patients with cirrhosis and normal or slightly increased Crea. Clinically it seems most important to identify renal dysfunction in these patients at an early stage before development of a hepatorenal syndrome denoting a poor prognosis. Therefore, other serum parameters such as cystatin C have been proposed to reflect renal function in cirrhosis [4] but have not been generally accepted yet. Published online: April 14, 2011