Chronic kidney disease (CKD) affects up to 3% of the general pet population, and a whopping estimated 10% of older dogs and 30% to 50% of geriatric cats. At some point as a pet owner, you or another owner you know will likely be impacted by this disease. Despite CKD’s high prevalence, many pets aren’t diagnosed until late in the disease course, when treatments are less effective. Here, our Oak Creek Veterinary Care team explains how and why early detection can improve outcomes and extend the lives of affected pets.

Chronic kidney disease causes in pets

CKD has many possible underlying causes, because the kidneys are sensitive, easily damaged organs. CKD is typically associated with senior pets and aging, and in most cases, no obvious underlying cause is found. Some pets who develop acute kidney injuries from toxins, infections, blood clots, immune disorders, urinary obstruction, surgical or anesthetic complications, or any other cause may develop CKD weeks or months after their injury resolves. Others, usually young or middle-aged pets, can fall victim to kidney disease because of a hereditary or genetic disorder. 

Chronic kidney disease signs in pets

During CKD’s earliest stages, when kidney cells are first damaged, the remaining cells step up and take on more work to keep kidney function relatively stable. This means that your pet will continue to look and act normally, despite their kidneys being damaged. Clinical signs appear only when two-thirds to three-quarters of kidney function is lost. 

Clinical signs are related to the kidneys’ decreased ability to do their jobs, which include regulating water balance, waste products, electrolyte, mineral, and protein concentrations, blood pressure, and blood cell production. Signs may include:

  • Increased thirst and urination
  • Decreased appetite
  • Nausea or vomiting
  • Bad breath
  • Lethargy
  • Weight loss
  • Unkempt appearance in cats
  • High blood pressure, which can lead to retinal bleeding or detachment and blindness

How most pets with chronic kidney disease are diagnosed

The International Renal Interest Society (IRIS) classifies CKD into four main stages, each with multiple substages. Each higher stage indicates progressively worsening kidney function and is associated with more severe clinical signs. Most pets do not have clinical signs during stages one and two, and therefore are not diagnosed until they reach stages three or four, when kidney function is greatly reduced and the pet is overtly sick. A combination of blood, urine, and imaging tests will reveal changes consistent with kidney disease, help our veterinary team determine the disease stage, and guide the treatment plan.

Early detection strategies for chronic kidney disease in pets

For years, veterinarians have known that early CKD diagnosis is key to successful treatment, but the available screening tools were imperfect. The most commonly used blood markers, blood urea nitrogen (BUN) and creatinine, can also be affected by muscle loss, dehydration, or non-kidney illness, making interpretation challenging in certain pets. Blood markers may also stay inside the laboratory’s published “normal” range during early disease stages, which makes them nearly impossible to detect. But, researchers have developed a new screening biomarker called symmetric dimethylarginine (SDMA), that solves this problem.

SDMA is a blood test included in a chemistry panel and interpreted alongside BUN, creatinine, and urinalysis results. SDMA may elevate up to 18 months before other blood markers change, and is a game changer for early CKD diagnosis. Running comprehensive wellness screening tests that include SDMA each year is the best way to detect stages one and two CKD before pets develop clinical signs and when about 60% of their kidney function remains.

Chronic kidney disease management in pets

CKD that is diagnosed during stages one and two responds extremely well to a therapeutic diet, which reduces the kidney’s workload and protects the remaining kidney cells. Existing damage cannot be reversed, but placing CKD pets on a kidney diet and avoiding kidney-toxic substances will greatly slow disease progression and extend their lifespan, likely by several years. Pets diagnosed in later stages or who live many years after diagnosis may also require medications, supplements, and at-home fluid administration to manage their symptoms and maintain comfort. Some pets diagnosed during late stages will not respond well to treatment and may pass away from kidney failure.

Reduced kidney function commonly affects the aging pet population, but you don’t have to sit back and wait for the disease to take hold. Proactive health management with routine wellness examinations and screening tests with our Oak Creek Veterinary Care team can identify CKD sooner, so we can implement a treatment plan that will add years to your pet’s life. Call us to schedule a visit or to learn more about the benefits of early CKD screening tests and early detection.