Measurement of Serum and Urine Neutrophil Gelatinase-Associated Lipocalin (NGAL) in Dogs with Chronic Kidney Disease, Lymphosarcoma, Carcinoma and Induced Endotoxemia to Assess Diagnostic Utility of NGAL in Dogs with Chronic Kidney Disease

Canine chronic kidney disease (CKD) is estimated to have a prevalence of 0.5-7%, and improved methods for the detection and monitoring of CKD are needed. Neutrophil gelatinase-associated lipocalin (NGAL), a protein detectable in blood and urine that increases secondary to renal dysfunction, is gaining utility as a renal disease biomarker in humans. The purpose of this study was to investigate serum and urine NGAL concentrations in normal dogs and dogs with naturally occurring CKD and then to assess the specificity by measuring serum and urine NGAL in dogs with other diseases. Forty-two dogs assessed to be free of urinary tract disease (normal history, physical examination, clinicopathologic results, and blood pressure measurement), 11 dogs with CKD, 21 dogs with lymphosarcoma, 12 dogs with carcinomas, and 16 dogs with induced endotoxemia were enrolled. Serum and urine NGAL concentrations were measured using a commercially available canine-specific ELISA kit. Serum and urine NGAL levels were elevated in dogs with CKD compared to that of normal dogs. Concentrations of both correlated with serum creatinine concentration and with glomerular filtration rate at 6 months. Serum NGAL concentrations lacked specificity for CKD. Urine NGAL concentration was most elevated in dogs with CKD, followed by dogs with carcinomas and lymphosarcoma. Serum and urine NGAL concentrations are elevated in renal and non-renal diseases, but may still be useful adjunct to current methods to diagnose and monitor CKD.