Urinary protein electrophoresis pattern is associated with prognosis in dogs with proteinuric chronic kidney disease

Canine chronic kidney disease (CKD) is a common condition with a highly variable prognosis. While associations between histopathological lesions and outcome have been reported, the prognostic value of urinary protein electrophoresis (UPE) has not been established. This study evaluated the association between admission urine proteins sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE) profiles and CKD progression and survival in dogs with proteinuric CKD. One hundred client-owned dogs were retrospectively included and classified using a semi-quantitative approach as having glomerular (n = 47), mixed (n = 40), or tubular (n = 13) electrophoretic profiles. Dogs with a tubular profile showed significantly faster disease progression, with an earlier 25% increase in serum creatinine (median, 2 vs. 24 months) and a steeper creatinine slope over the first year (56 vs. 7 µmol/L/month), compared with glomerular cases. Tubular profiles were also associated with significantly shorter CKD-related survival (median, 1 vs. 55 months), independently of other biochemical variables. Mixed profiles were likewise associated with reduced survival compared with glomerular profiles (median, 12 vs. 55 months). These results suggest that admission UPE profiles are associated with CKD progression and survival and support the inclusion of SDS-AGE in the initial evaluation of dogs with proteinuric CKD. Further studies are needed to determine the clinical and therapeutic implications of these findings.