Title: Neutrophil Gelatinase-Associated Lipocalin (NGAL) as a marker for progressive decline in kidney function

PI: Thomas Nickolas, MD

NGAL is a member of a family of over 20 proteins called lipocalins which function in intracellular chemical signaling. NGAL is one of the first molecules to trigger kidney development, expressed by the ureteric bud. It has been shown to convert embryonic mesenchymal cells into epithelial cells which form tubules and then complete nephrons. Although NGAL plays a role in early kidney development, its role in adult life has not been well defined, but it is overexpressed in states of inflammation and malignancy.

NGAL is present in the kidney proximal tubule in a patchy distribution and has recently been found to be expressed in patients with chronic kidney disease (CKD). The level of NGAL expression appears to be related to the degree of kidney dysfunction and may even be able to predict which patients are going to have a faster decline in their kidney function.

We purpose a longitudinal study whereby urine and serum levels of NGAL are measured in patients that have CKD. This will be the first study to measure NGAL expression patterns in the CKD population. If NGAL can be used as a predictive tool to identify patients at high risk for kidney disease progression, it will lead to studies of its use to guide therapeutic regimens to retard the progression of kidney disease.

Inclusion Criteria:

1) Age greater than 18 years

2) Kidney disease as defined by an estimated glomerular filtration rate (eGFR) < 60 mL/minute or normal kidney function in the presence of proteinuria.

Exclusion Criteria:

1) Presence of severe systemic disease that will reduce life expectancy to < 2 years as defined by the following diseases:

a. Malignancy other than nonmelanoma skin cancer within the last 3 years

b. Class IV heart failure

c. Cirrhosis or End Stage Liver Disease

d. End Stage AIDS

e. Acute Renal Failure

f. Weight loss > 10% in the last 6 months not secondary to CKD