Chronic kidney failure, CIN, is the most common form of kidney disease in dogs and among the most common causes of death in older dogs.
Unfortunately, chronic disease progresses over a period of years and often goes unnoticed by even the most vigilant owners. When signs finally appear, the disease is often well-advanced. But, with proper treatment and monitoring, some dogs with chronic kidney failure live comfortably for years after diagnosis.
Dogs with the chronic disease, CIN, tend to produce large amounts of dilute urine (polyuria), because there aren’t enough healthy nephrons to properly filter and reabsorb excess water back into the bloodstream. Consequently, dogs with chronic renal failure drink lots of water (polydypsia) to maintain the right volume of internal fluids.
CIN can lead to the progression of acute kidney failure or result in the destructive diseases that slowly destroy nephrons. One such long-term condition is glomerulonephritis, in which immune-system proteins damage the glomerulus (the tuft of blood vessels at the entrance to the nephron). But, more often than not, it’s impossible to identify the exact cause of CIN.
Intravenous fluid therapy can temporarily help dogs that have acute or chronic kidney failure. Other medications may also be used in the treatment of renal disease. When kidney failure occurs, many other organs are affected by the increased toxins not effectively eliminated by the kidney. One major organ is the stomach. The stomach lining becomes inflamed and ulcerated due to the increase in urea nitrogen in the blood stream. H2 blockers, such as cimetidine, assist in reducing the stomach irritation. To help keep levels of phosphorus under control, phosphate binders are given orally. These include aluminum hydroxide, aluminum carbonate, calcium carbonate, and calcium acetate. One produce we use is Alternagel, available at most pharmacies located where the antacids are kept.
Renal failure can also cause hypertension or high blood pressure. Sodium restriction is the initial step in the management of this disease. Drugs may be incorporated if hypertension is not controlled by dietary management.
We also recommend B-complex and vitamin C to help the well being of your dog and also replenish the vitamins lost due to the inability of the kidneys to recycle and retain the nutrients in the body properly. Sodium bicarbonate may also be of use to aid in controlling the changes in the acidity of the blood. If hypertension or heart failure are present, we avoid the use of this medication.
Other medications that may be used are androgens or erythropoiten (hormones to help reduce the anemia associated with kidney disease), and calcitriol, a substance which helps regulate the levels of calcium and phosphorus.Some urologists are now recommending treating with calcitriol as soon as kidney disease is diagnosed. The dose is 2.5ug/kg every day. If phosphorus levels are above 6, this drug should not be administered. ACE inhibitors, such as enalapril are also recommended in early stages of kidney disease as long as renal functions are monitored. Additional vitamins or nutritional supplements for slowing the progression of CIN may be beneficial. These products are fish oils containing the Omega 3 fatty acids in conjunction with vitamin E which may help reduce kidney inflammation.Omega 3 oils slow may slow the progression of renal failure. Vitamin E acts synergistically with the Omega 3’s. Also, omega 3 fatty acids may deplete vitamin E in the body, another reason to supplement this vitamin.Veterinarians sometimes resort to more intensive treatments. For example, veterinary specialists can perform dialysis (artificial blood filtering) and kidney transplants. However, dialysis and transplants are labor- and technology-intensive – and therefore very expensive. Dialysis requires several hours of treatment several times a week – on an ongoing basis. And canine kidney transplants have produced few long-term survivors, probably because the genetic diversity among dogs increases the risk of organ rejection or some other factor that we do not understand at this time. Future advances in anti-rejection drugs may make kidney transplants a more viable option for dogs, although cost considerations may still limit this practice.
The key to ongoing CIN treatment takes place at home, where owners can take several steps to help their dogs. Make sure a dog with CIN always has access to fresh water. To encourage the dog to drink and eat, maintain a steady, stress-free daily routine. (Stressed-out dogs often stop drinking and eating, further jeopardizing kidney function.)
Dietary management can also help your dog. This consists primarily of restricting the amount of protein, phosphorus, and sodium in the diet, while providing adequate amounts of non protein calories, vitamins, and minerals. But not every dog with kidney disease needs such a diet.
Renal Failure Diets-(these are some suggestions-but your veterinarian may have others)
Diet KCAL Protein
HILLS 350KCAL/CUP 12.7%
SELECT-CARE 362KCAL/CUP 12%
CNM-NF 415KCAL/CUP 12%
CNM-CV 638KCAL/CAN 12.3%
HILLS UD 791KCAL/CUP 8%
Homemade diets: Cooking instructions
Mix the rice, calcium carbonate, corn oil and salt. Cook according to instructions for the rice. Add remaining ingredients except the vitamins . Simmer 10 minutes and cool. Add vitamins before feeding.
7% Diet: 1068 KCAL
3/4 cup raw rice; 1 large egg; 1 oz. liver; 3 Tbsp. bacon fat; 1 tsp. corn oil; 3/4 tsp. calcium carbonate (Tums); 1/4 tsp. iodized salt
12% Diet: 1145 KCAL
2/3cup raw rice; 2 large eggs; 1/3 cup low-fat cottage cheese; 1 oz. liver; 3 Tbsp. bacon fat; 1tsp corn oil; 3/4 tsp. calcium carbonate(Tums) ; 1/4 tsp. iodized salt.
16% Diet: 1119 KCAL
2/3 cup raw rice; 1/2 cup diced poultry; 1/3 cup low-fat cottage cheese; 1 oz. liver; 3 Tbsp. bacon fat; 1 tsp. corn oil; 3/4 tsp. calcium carbonate (Tums); 1/4 tsp. iodized salt.
Approximate feeding recommendations: Please check with your veterinarian.
Body wght (LB)Approx.-KCAL/Dy Can- Dry
5 230 1/3- 3/4
10 390 2/3 -11/4
20 650 1 – 2
30 885 11/3 -23/4
40 1090 12/3 -31/2
50 1300 2 -31/2
60 1480 21/4 -43/4
70 1675 21/2 -51/2
80 1850 23/4 – 6
90 2020 3 – 61/2
100 2185 31/3 – 7
110 2350 31/2-71/2
120 2505 33/4 – 8
130 2660 4 – 81/2
140 2815 41/2- 9
150 2965 5 – 91/2
Studies suggest that feeding your dog a diet low in phosphorus may help slow the progression of kidney failure by reducing mineral deposits in the kidneys. And while there’s no conclusive proof that low-protein diets slow CRF in dogs, your pet may feel better on such a diet. Low-protein diets generate fewer nitrogenous wastes – high levels of which can cause nausea and vomiting in dogs with kidney disease. A cautionary note: low-protein diets, if not carefully managed, can lead to malnutrition. So be sure to consult your veterinarian before making any such dietary changes.
Above all, keep a watchful eye. Report any changes in your dog’s eating, drinking, and elimination habits to your veterinarian. Such changes may alert your veterinarian to the possibility of kidney disease – or help your practitioner adjust treatment if therapy has already begun.
With kidney disease, your dog becomes less alert, loses its appetite, and may vomit. Take your dog to your veterinarian if it shows any of the following signs that sometimes (but not always) point to kidney disease:
1. Increased thirst and urine volume
2. Weight loss
3. Weakness and exercise intolerance
4. Tendency to bleed or bruise easily