FR
ENWhat is kidney disease?
The kidneys work continuously: filtering waste from the blood, regulating blood pressure, and producing hormones. When their function progressively deteriorates, waste accumulates in the blood and the whole body feels the effects. Kidney disease can be acute (sudden onset, sometimes reversible) or chronic (slow progression, generally irreversible).
Waste filtration
Elimination of urea, creatinine, and other metabolic toxins through the urine.
Blood pressure regulation
Control of blood pressure through fluid management and certain hormones.
Hormone production
Stimulation of red blood cell production via erythropoietin.
Mineral balance
Regulation of phosphorus, potassium, calcium, and other essential electrolytes.
Acute vs chronic: an important distinction
Sudden onset, often caused by poisoning (antifreeze, medications), severe infection, or circulatory shock. Potentially reversible if treated quickly and aggressively.
Progressive and irreversible deterioration of kidney function over months to years. Most common in older dogs. Long-term management aims to slow progression.
Silent loss of function
65 to 75% of kidney function must be lost before standard blood tests detect the problem. SDMA, a more sensitive biomarker, allows earlier detection. This is why annual check-ups in older dogs are so important.
Possible causes
- Congenital abnormalities (birth defects)
- Bacterial or viral infections, Lyme disease
- Autoimmune diseases attacking kidney tissue
- Kidney stones (nephrolithiasis)
- Exposure to toxins: antifreeze (ethylene glycol), grapes, certain medications
- Complications from acute kidney injury
- Unknown cause (very common, especially in older dogs)
Stages of chronic kidney disease
The IRIS (International Renal Interest Society) system classifies CKD into 4 stages based on serum creatinine and SDMA. This classification guides treatment decisions and provides a realistic picture of prognosis.
Signs and symptoms
Kidney disease symptoms develop gradually, often confused with normal aging. The accumulation of toxins (uremia) affects appetite, energy, the digestive tract, and ultimately the nervous system.
Early stage
- •Tires quickly, sleeps more
- •Mild to moderate weight loss
- •Strong, uremic breath
- •Poor appetite, mild nausea
Intermediate stage
- •Polyuria (urinating a lot)
- •Polydipsia (drinking more)
- •Vomiting, diarrhea
- •Panting, excessive drooling
- •Dull coat, reclusive behavior
Advanced stage
- •Sunken eyes, visible dehydration
- •Mouth ulcers
- •Unsteady gait, confusion
- •Abnormal vocalizations
- •Marked muscle wasting
When to seek immediate help?
These signs indicate acute decompensation. Bring your dog to an emergency clinic without delay:
- Severe respiratory distress or uncontrollable panting
- Inability to walk, sudden collapse
- Seizures
- Bluish gums or tongue (cyanosis)
- Uncontrollable vomiting or diarrhea
- Crying or whimpering in pain
- Extreme agitation or coma
How is the diagnosis made?
Diagnosing kidney disease requires a combination of tests: symptoms alone are not sufficient, as they often appear late. Regular screening in older dogs is the best way to catch the problem early.
Blood tests
Creatinine, urea, and SDMA reflect the kidneys' filtration capacity. SDMA changes as soon as 25% of function is lost, well before creatinine. The panel also includes electrolytes (phosphorus, potassium, calcium) and a complete blood count (for anemia).
Urinalysis
Urine specific gravity (concentration) is the first value to deteriorate. Overly dilute urine signals that the kidneys are no longer concentrating properly. The presence of protein (proteinuria) and sediment helps characterize the type and severity of damage.
Imaging
Abdominal ultrasound visualizes the size, shape, and texture of the kidneys. Small, irregular kidneys are typical of advanced CKD. X-rays and ultrasound also detect kidney stones, cysts, or tumors.
IRIS staging
Once the values are known, the veterinarian classifies the disease into stage 1 through 4 using the IRIS system. This stage guides treatment, monitoring frequency, and allows for an honest conversation about prognosis.
An important fact: a dog can appear completely normal at CKD stages 1 and 2. Incidental discovery during a routine blood panel is common. This is one of the strongest arguments for annual blood screening in any dog over 7 years old.
Treatment and management
There is no cure for CKD. The goal is to slow progression, control complications, and maintain quality of life for as long as possible. A multimodal approach is essential.
Renal diet
- Specially formulated foods with reduced protein and phosphorus to decrease the kidneys' workload
- Wet or moistened food to increase fluid intake
- Gradual transition over 2 to 4 weeks to improve acceptance
- Strictly avoid salty treats, table food, and phosphorus-rich foods
Hydration
- At-home subcutaneous fluids: most owners learn the technique after a quick training session
- Multiple water stations, water fountain, filtered water
- Intravenous fluid therapy during crises or hospitalizations
- Monitor daily water intake
Supportive medications
- Phosphate binders (given with meals) to reduce intestinal phosphorus absorption
- Antihypertensives (ACE inhibitors, amlodipine) if high blood pressure is present
- Erythropoietin or erythropoiesis-stimulating agents if severe anemia
- Anti-nausea medications (maropitant), appetite stimulants
- SAMe, silymarin (milk thistle) for hepatic support
Regular monitoring
- Blood and urine tests every 3 to 6 months depending on stage
- Blood pressure measurement at each visit (hypertension accelerates CKD)
- Urine protein-to-creatinine ratio (UPC) to monitor proteinuria
- Regular home weigh-ins to catch early weight loss
What to expect long-term?
Prognosis depends on the stage at diagnosis, the underlying cause (if treatable), and the response to treatment. CKD is incurable, but many dogs live comfortably for months to years after diagnosis.
Treatment decisions and prognosis discussions are based on the IRIS stage. Ask your veterinarian which stage your dog is in and what that means practically for their daily life and long-term care.
Home management
Comfort adjustments
Elevated bowls and multiple water stations throughout the home
Filtered water to encourage drinking (reduces unwanted minerals)
Warm, quiet resting area away from noise
Ramps or steps to access furniture if the dog is weakened
Non-slip surfaces to prevent falls
At-home subcutaneous fluids after training by the veterinary team
Essential actions
- Follow the prescribed renal diet strictly, without exception
- Daily monitoring: appetite, water intake, urination, vomiting, weight
- Administer all medications on schedule
- Weigh the dog weekly (early weight loss is a warning sign)
- Keep all blood monitoring appointments
- Encourage gentle physical activity according to the dog's energy level
- Consult promptly if repeated vomiting, sudden appetite loss, or marked lethargy
- Avoid all NSAIDs (anti-inflammatories) without explicit veterinary guidance
Never do
- Give NSAIDs (aspirin, ibuprofen, meloxicam) without a prescription: they worsen CKD
- Change the diet without consulting (some seemingly healthy foods are harmful)
- Dismiss weight loss as normal aging in an older dog
- Skip follow-up appointments when the dog seems to be doing well
Frequently asked questions
My dog has elevated creatinine but seems normal. Is this serious?
My dog refuses the renal diet. What can I do?
At-home subcutaneous fluids: is this really manageable?
What is the difference between acute kidney injury and chronic kidney disease?
My dog has been drinking a lot for a few weeks. Could it be kidney disease?
How long can my dog live with chronic kidney disease?
This guide is provided for informational and educational purposes only. It does not constitute veterinary medical advice and is not a substitute for a consultation with a qualified veterinarian. Every animal is unique and their health must be evaluated individually. If you have concerns about your pet's health, contact our clinic or consult a veterinarian promptly.