Cats with plasma cell pododermatitis often have kidney disease too

Abstract

Case series summary The medical records from 25 cats with feline plasma cell pododermatitis (PCP) and concurrent glomerular disease presenting between 2017 and 2025 were reviewed. The aim of this study was to highlight that feline patients with PCP may be predisposed to glomerular disease and to document the clinical presentations of these patients. Inclusion criteria included diagnosis of PCP by physical examination or histopathology and diagnosis of glomerular disease via renal histopathology or urine sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). Data collected included signalment, physical examination findings, clinicopathologic parameters, imaging results, urinalysis, urine SDS-PAGE results, renal histopathology, treatment protocols and survival times. Affected cats were most commonly young (aged <5 years) and castrated males. Clinicopathologic abnormalities included marked anemia, hyperglobulinemia and proteinuria, although urine protein:creatinine ratios varied widely between patients. Renal ultrasound findings were typically non-specific. Urine SDS-PAGE consistently demonstrated evidence of glomerular dysfunction, and renal histopathology demonstrated immune complex glomerulonephritis in 14/17 (82%) cases. Immunosuppressive therapy was the primary treatment for renal disease but was often delayed owing to challenges diagnosing glomerular dysfunction as the underlying cause of renal disease. Median survival times after onset of renal disease were short, at approximately 1 month. Relevance and novel information Our findings suggest that PCP, particularly in young males, can be associated with concurrent glomerular disease, which is often immune mediated in nature. Urine SDS-PAGE may be useful in identifying underlying glomerular damage. Median survival times in these patients are short, emphasizing the need to closely monitor cats presenting with PCP for evidence of developing glomerular disease.