Kidney Disease in Dogs: Causes, Symptoms and Treatment

Written and verified by the biologist Paloma de los Milagros

Last update: 27 December, 2022

The kidneys have a number of vital functions, including filtering blood and removing any waste products through urine. Kidney disease in dogs can therefore pose a significant risk to their health. However, diet can play a key role in preventing the disease.

Kidneys help to manage hydration levels. This means that they play a fundamental role in maintaining homeostasis, blood pressure, and electrolyte balance. In addition, the kidneys secrete hormones that stimulate the production of red blood cells, among other things. Kidney failure is one of the most common renal diseases in dogs and it can become chronic.

At least one of a kidney’s functions has to be affected in order for a doctor or vet to be able to diagnose kidney failure. However, diagnosis isn’t sometimes possible until the disease has reached a late stage, which is why treatment is often complicated. 

Causes and symptoms of kidney disease in dogs

According to the International Renal Interest Society (IRIS), a group of vets dedicated to researching kidney failure in cats and dogs, the main risk factors are:

• Glomerulonephritis, or inflammation of the glomeruli, which are small filters inside the kidneys
• Pyelonephritis or renal infections
• Nephrolithiasis or kidney stones
• Leptospirosis, a disease caused by Leptospira interrogans, which is transferable to humans
• Cancer
• Amyloidosis, a condition caused by a build-up of the natural protein “amyloid” in organs and tissues

Older dogs are at a higher risk of developing any of the above conditions. It’s therefore important to take preventative measures early on.

The most obvious symptoms of kidney failure are polyuria and polydipsia. These conditions cause the sufferer to urinate and drink more than usual. Other possible indicators are incontinence, lethargy, loss of appetite and weight, bad breath, and mouth ulcers.

Treating kidney disease

The length of kidney disease and the seriousness of the condition are two key factors that affect treatment. For example, acute kidney disease can be the result of accidentally ingesting toxins. It can also be the result of the body rejecting a previous drug treatment.

In addition, this type of condition can occur if a dog eats grapes or raisins. As the symptoms can appear quite suddenly, the best form of treatment is to take the dog to hospital. You should then ensure they receive fluids and are put on a special diet for dogs with kidney disease.

In chronic cases, dogs can suffer from this disease for months, years, or even their entire lifetime in congenital cases. Early detection is really important in these cases. In fact, it’s the owner’s responsibility to keep an eye on their pet and give them the attention they need.

The importance of diet

Once kidney failure is diagnosed, it can be difficult to identify the exact cause, however the vet will still be able to prescribe a palliative treatment. The three most important steps in treating kidney failure are taking the prescribed medication, receiving fluid therapy and following a “renal diet”.

Concerning diet, there are several specialty feeds that you can give your dog. However, there are also some recommended homemade alternatives. Whichever type of feed you choose, there are some nutritional requirements that it must meet:

• It must be low in phosphorus. This is to help slow the progression of nephropathy, which is the general deterioration of kidney function
• The feed must have alkaline supplements to help counteract metabolic acidosis, the over-production of acid
• It shouldn’t have more than 1.5 oz of protein per 1,000 kcals of feed. This is to reduce the levels of urea in the blood
• The feed must have a high omega-3 fatty acid content to help increase glomerular filtration. This is the process by which the kidneys filter waste products from the blood