There are no early markers for acute or chronic renal disease. Serum creatinine levels rise only after there has been significant renal impairment and injury. It is important to note that the earlier renal disease or injury is identified, the more successfully it can be treated. Early treatment also helps to lower the morbidity associated with the disease. This is particularly important in patients who have serious nonrenal disease (e.g., heart surgery, renal transplant, sepsis). In these patients, severe acute kidney injury (AKI) increases morbidity and mortality of hospitalized patients.
NGAL is a member of the lipocalin family of proteins, which bind and transport small lipophilic molecules. NGAL is generally expressed in low concentrations from the renal tubules, but it increases greatly in the presence of epithelial injury and inflammation. A marked elevation in NGAL indicates that renal injury has occurred and aggressive supportive treatment should be instituted. NGAL concentrations rise 48 hours before a rise in creatinine is noted. NGAL can be detected in both urine and blood within two hours of a renal insult.
NGAL is a predictor for Acute Kidney Injury (AKI) which is referred to in the past as Acute Renal Failure. NGAL is a also a marker of Chronic Kidney Disease. NGAL can be measured in the urine, plasma, or serum samples with ELISA test kits. Results are available in less than 1 hour in a standard laboratory with conventional ELISA equipment. This is particularly helpful in an intensive care environment. By itself, the absolute baseline laboratory result is not as important as are the succeeding results. Normal values vary according to which laboratory method is used and the patient’s baseline GFR. NGAL varies inversely with the GFR. Urine or blood samples can also be analyzed using an established and validated enzyme immunoassay (EIA).
NGAL measurements are being used increasingly in a range of medical circumstances contributing to Acute Kidney Injury or Chronic Kidney Disease. Medical situations that lead Acute Kindy Injury where NGAL measurments is used include cardiac surgery, kidney transplantation, contrast nephropathy, and hemolytic uremic syndrome. It is also used in the intensive care evnironments. The situations that cause Chronic Kidney Disease where NGAL is used include lupus nephritis, glomerulonephritis, obstruction, dysplasia, polycystic kidney disease, IgA nephropathy, renal dysplasia, obstructive uropathy, and glomerular and cystic diseases).
Indications of High Neutrophil Gelatinase–Associated Lipocalin Levels
Renal Injury causes the Neutrophil Gelatinase–Associated Lipocalin levels to increase. Increased in NGAL levels can be an indication of either Primary or Secondary Renal Disease.