The 4 Most Common Kidney Disease Types in Dogs

Kidney disease in dogs can manifest in several forms and at various stages of life. The kidneys play a vital role in filtering waste products from the blood, regulating fluid balance, and producing hormones. When kidney function declines, it has wide-ranging effects on the body. Understanding the types, causes, symptoms, and management options for kidney disease can help dog owners respond effectively and support their pet’s wellbeing.

Types of Kidney Disease in Dogs

Acute Kidney Injury (AKI)

Acute kidney injury occurs when kidney function deteriorates suddenly, often over hours to days. It can be caused by toxin ingestion (such as antifreeze, grapes or raisins, certain medications, or lilies), severe infections (such as leptospirosis), urinary obstruction, or severe dehydration. AKI is a medical emergency and requires immediate veterinary treatment. With prompt and aggressive treatment, some dogs make a partial or full recovery, though others may develop chronic kidney disease as a consequence.

Chronic Kidney Disease (CKD)

Chronic kidney disease involves a gradual, progressive loss of kidney function over months or years. It is more common in older dogs and may have various underlying causes, including immune-mediated conditions, recurrent infections, high blood pressure, or primary kidney disease. CKD is staged from 1 (mild) to 4 (severe) based on blood creatinine levels and the presence of proteinuria and hypertension. Most dogs with CKD are diagnosed at stages 2 or 3, as stage 1 is usually asymptomatic.

Common Causes of Kidney Disease in Dogs

• Toxin ingestion (antifreeze/ethylene glycol, grapes/raisins, NSAIDs, certain antibiotics, lilies)
• Infections, particularly leptospirosis (a bacterial infection that directly damages kidneys)
• Glomerulonephritis (immune-mediated inflammation of the kidney filtration units)
• Polycystic kidney disease (hereditary in certain breeds)
• Pyelonephritis (kidney infection)
• Amyloidosis (protein deposition in the kidneys, more common in certain breeds)
• Congenital abnormalities
• Dental disease (bacteria entering the bloodstream from diseased gums can affect the kidneys over time)

Symptoms of Kidney Disease in Dogs

Early-stage kidney disease is often asymptomatic. Common signs that appear as kidney disease progresses include:

• Increased thirst and urination (PU/PD)
• Loss of appetite and weight loss
• Vomiting and nausea
• Lethargy and weakness
• Bad breath with a chemical or ammonia smell (uraemic breath)
• Mouth ulcers
• Anaemia (pale gums)
• Changes in urination frequency or amount

Diagnosis

Diagnosis typically involves blood tests (measuring urea, creatinine, SDMA, phosphate, and other markers), urinalysis (including urine specific gravity and protein-to-creatinine ratio), blood pressure measurement, and imaging (ultrasound to assess kidney structure). SDMA is a newer, sensitive marker that can detect kidney disease earlier than creatinine alone.

Management of Kidney Disease in Dogs

Management aims to slow progression, manage symptoms, and maintain quality of life. Key elements include prescription kidney diets (restricted in protein, phosphorus, and sodium), ensuring adequate hydration (subcutaneous fluids at home are commonly taught to owners of dogs with CKD), blood pressure control, phosphate binders if needed, treatment of concurrent infections or underlying conditions, and monitoring for anaemia. Regular veterinary monitoring is essential to adjust treatment as the disease progresses.