Serum uromodulin in dogs with chronic kidney disease.

Abstract

Serum uromodulin concentration has been described as a novel biomarker of chronic kidney disease (CKD) in humans but not dogs. To evaluate the serum uromodulin concentration in dogs with CKD and assess its diagnostic performance in distinguishing dogs with CKD from healthy dogs. Forty-nine dogs with CKD (International Renal Interest Society[IRIS] Stage 1, n=23; Stage 2, n=20; Stage 3-4, n=6) and 25 healthy controls. Prospective, observational study. Serum uromodulin concentration was measured using a canine-specific enzyme-linked immunosorbent assay (ELISA), and its correlation with conventional renal markers was analyzed. Serum uromodulin concentrations were significantly lower in the CKD group than in the control group (P < .001), but no significant difference was observed among stages of CKD. A negative correlation was observed between serum uromodulin concentration and conventional renal markers (blood urea nitrogen concentration, r=-.60, P < .0001; serum creatinine concentration, r=-.46, P < .0001; serum symmetric dimethylarginine concentration [SDMA], r=-.65, P < .0001). In receiver operating characteristic analysis, the area under the curve (AUC) of uromodulin (AUC, 0.97; 95% confidence interval [CI], 0.94-1.00) was higher than that of SDMA (AUC, 0.87; 95% CI, 0.79-0.95) for CKD diagnosis (P=.01). The AUC of uromodulin (AUC, 0.95; 95% CI, 0.89-1.00) also was higher than that of SDMA (AUC, 0.72; 95% CI, 0.58-0.87) in distinguishing dogs with Stage 1 CKD from controls (P=.001). Serum uromodulin concentration is decreased in dogs with CKD. Thus, serum uromodulin may be a valuable diagnostic marker for CKD in dogs, particularly in identifying early-stage CKD.