Introduction

There are few techniques available to detect the early impairment of renal function in a cost-effective and easy methodology. Some molecules that have been recently advocated for in the diagnosis of kidney disease in humans, have also been tested in dogs with renal disease, showing promising results.

Objectives

The aim of the present study was to evaluate two new serum markers, beta-2-microglobulin (B2M) and cystatin C (CysC), for the diagnosis of renal diseases in dogs.

Methods

A total of 75 dogs were included and classified in groups depending on the pathology: CKD (20), urinary tract pathologies other than CKD (18), leishmaniasis (16) and systemic diseases (21). Twenty healthy dogs were in the control population.

Retrospective analysis of serum and urine samples collected was performed. Serum levels of CysC (sCysC) and B2M (sB2M) were determinate with a particle-enhanced immunoturbidimetric assay (PETIA) method. Results were correlated with serum creatinine (sCr), BUN, phosphorus concentrations (P) and urinary protein-to-creatinine ratio (UPC); and compared between groups.

Results

All serum biomarkers, except B2M, distinguished dogs with renal disease from normal dogs (p < 0,001) and/or dogs with other diseases (p < 0,01). In dogs with evidences of renal damage, sCysC correlated most strongly with sCr (r = 0,69), P (r = 0,79) and UPC (r = 0,83), (p < 0,05). However, B2M was not correlated with other biomarkers.

Conclusion

sCysC showed to be more specific and sensible to detect kidney damage than B2M; consequently, sCysC would be more useful in the application of future protocols for diagnosis of renal diseases in dogs.