Dog Protein-Losing Nephropathy: Kidney Disease and Protein Loss

Protein-losing nephropathy is a serious kidney condition in dogs where the filtration barrier fails, causing massive protein loss in urine and leading to life-threatening complications including fluid accumulation and thromboembolism.

Key Facts

PLN involves damage to the glomeruli, the kidney's filtration units, allowing protein to leak into urine
Protein loss leads to low blood protein levels (hypoalbuminemia) causing fluid to accumulate in the abdomen and chest
Soft Coated Wheaten Terriers and Bernese Mountain Dogs have genetic predispositions to PLN
Thromboembolism (blood clots) is a major and often fatal complication of severe protein loss
Diagnosis requires urinalysis showing protein, blood protein measurement, and kidney biopsy for definitive diagnosis
Immune-mediated causes are common and respond partially to immunosuppressive therapy
Dietary protein restriction and anti-proteinuric medications are cornerstones of management

Welfare Considerations

Dogs with PLN face progressive deterioration from multiple fronts simultaneously. The accumulation of fluid in the abdomen (ascites) causes visible discomfort and breathlessness. The protein deficit weakens muscles, impairs immune function, and reduces healing capacity. Blood clot formation can cause sudden stroke-like events or pulmonary embolism causing acute respiratory distress. Many affected dogs deteriorate despite aggressive treatment. The management of PLN requires frequent veterinary monitoring, complex medication protocols, and dietary management that imposes ongoing burdens on both dog and owner. Predisposed breeds should be screened with annual urinalysis to catch early disease before severe protein loss occurs.

What You Can Do

Screen Soft Coated Wheaten Terriers and Bernese Mountain Dogs annually with urinalysis from age 2-3
If your dog is diagnosed with PLN, work with a veterinary internist for optimal management
Follow prescribed dietary restrictions and medication protocols carefully
Monitor for signs of fluid accumulation, breathing difficulty, or sudden weakness requiring emergency care
Support breed health committees working to reduce the prevalence of PLN through selective breeding