Kidney or Renal Disease by Dr. Becky Marks
Kidney disease is common cause of death in our older pets (cats, dogs, birds, guinea pigs). It seems to be a silent disease in pets until it becomes very severe. Veterinary medicine continues to explore new diagnostic tools and treatments.
The body has two kidneys.These organs lay under the last ribs of the body on the left and right side. The role of the kidneys is to filter waste products and to recycle useful components of the blood.Lets try the analogy of a screened window. It keeps the flies out (bad) and always fresh air (oxygen) in. If you get a tiny hole in the screen you will have some ants creep through. The large the hole allows a wasp to creep through. All the blood is screened through the kidneys. If there is a medication, infection or toxins in the system healthy kidneys can handle small amounts. Damaged kidneys a limited in this function. Even an antibiotic may become harmful to a poor kidney.
The result is a concentration of the bad products . They stay in the bloodstream because they couldn’t get filtered out. The worst of these is the end product of protein. Protein gets broken down into “ammonia”. Small amounts are normal but in large amounts are poisonous. On blood work the raised blood ammonia levels are the first indication of kidney disease. Then other numbers begin to rise, too. When we see changes on the blood work it means the kidneys are working at about 1/4 of their normal function or conversely they have lost 3/4 of normal function. As the toxins begin to build up vomiting occurs. Until that point a pet owner may not see any changes. Weight loss, increased thirst and urination and lethargy are usually present.
Now there is an earlier detection test available called the Early Renal Detection test (ERD). It is a test on the urine which measures small molecular weight proteins. As we go back to the analogy of our window screen remember that a small hole lets small ants in. Lets call these small proteins. They are detectable on this test. The blood test can only measure the wasp size insects or large proteins. The early detection is so beneficial because the changes in diet may be all that is necessary. It is a breakthrough in diagnosis of kidney disease! The test is currently available for dogs only but a cat version is soon to be released ( in months).
Treatment of moderate or severe kidney disease is possible. However, not all animals will respond. Usually these patients require hospitalization, fluids and medication. However, if the mild disease is identified early your pet has a much great chance of improvement and longevity. In addition the treament may be a simple diet change. The key is having screening tests done. Don’t wait until your companion is lethargic or vomiting. Allow your veterinarian to perform these simple tests as they enter their senior years ( 7 years old and upward).