Chronic Renal Insufficiency
The kidneys act to remove waste products from the blood stream, retain essential nutrients such as potassium, maintain hydration and produce urine.
Clinical signs of chronic renal insufficiency (CRI) are most commonly seen in older cats, and usually take place when at least 70% of the kidneys are dysfunctional. Some clinical signs of CRI are an increase in water consumption and urine output, weight loss, poor coat quality, decrease in appetite, bad breath, mouth ulcers, lethargy and depression.
Some causes of CRI are congenital malformations of the kidneys, bacterial and viral infection, tumors, damage to the kidney filtration membrane, or an unusual build-up of protein in the kidney.
CRI is diagnosed by looking at the levels of two waste products in the bloodstream, blood urea nitrogen (BUN) and creatinine, as well as the urine concentration. Tests to measure the blood levels of other substances, like potassium, phosphorus and calcium, as well as the red and white blood cell counts, can also be important in order to determine the best course of treatment.
We recommend that all senior pets (8+ years) have a least annual blood work, blood pressure and urinalysis to diagnose kidney disease at its earliest detectable level. A low urine concentration may indicate that at least two-thirds of the kidney tissues are damaged.
There is no cure for CRI. There are several options for management of the disease. A few options include:
Subcutaneous or Intravenous Fluid Therapy: Cats with CRI cannot maintain their hydration levels, which makes them feel poorly and further damages the kidneys. Cats with renal insufficiency can sometimes be maintained with subcutaneous fluid administration performed in our office or at home.
Renal/Kidney Diets: Feeding low protein and low phosphorus diets lowers the level of waste products in the bloodstream. These diets are only available with a prescription from a doctor.
Phosphate Binders: Despite low phosphate in the diet, blood phosphorus levels remain above normal in some cats. Reducing these levels has a major effect on improving your cat's well being and slowing disease progression. This is generally achieved by giving oral medication.
Antibiotics: Many cats with CRI are susceptible to urinary tract infections; these cats may benefit from antibiotic therapy.
Potassium Supplementation: Cats with renal insufficiency tend to lose too much potassium in the urine. This leads to muscle weakness, inappetance, stiffness and poor hair quality. Low potassium levels may also contribute to the worsening of the kidney failure.
It is important that fresh water is available at all times because cats with renal failure tend to dehydrate rapidly.
Unfortunately, once the kidneys are damaged, they have very limited ability to recover. CRI is a progressive disease, but, with treatment, your cat may have several years of good quality and active life.