Cushings Disease & Kidney Failure in Dogs

Dogs with Cushing's disease need regular checkups with the vet.
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Cushing's disease is a complex condition that affects your pup's adrenal glands, which produce the important hormones that regulate many of Fido's organs, including his kidneys. This condition can make your pup prone to suffering disorders, like kidney disease, diabetes and liver disease. Kidney disease, if left untreated or if it isn't monitored by your vet, eventually could result in kidney failure and death.

Cushing's Disease and Its Effects

If your pup has been diagnosed with Cushing's disease, it means that his body is producing too much cortisol, a natural steroid hormone. Cortisol is made by his adrenal glands, which are located right near his kidneys. This hormone is used by his body to help regulate many of his vital bodily functions and to deal with stress. Unfortunately, too much cortisol can lead to infections, because it suppresses the immune system. Cushing's disease usually is caused by a tumor on the pituitary gland, located at the base of the brain, which triggers the adrenal glands to produce cortisol. It also can be caused by a tumor on an adrenal gland.

The Connection Between the Kidneys and Cushing's Disease

The excess cortisol produced in Fido's body due to Cushing's disease can cause high blood pressure, because this hormone helps to regulate and maintain his blood pressure. High blood pressure can result in kidney damage and kidney failure if its cause isn't treated, warns Ron Hines, DVM of Cushing's disease not only raises your pup's blood pressure, it also suppresses his immune system, which can result in bladder and kidney infections. These infections could damage the kidneys and lead to kidney failure. In some cases, if an adrenal gland tumor is the cause of your pup's Cushing's disease, that tumor could spread to the kidneys, leading to kidney failure.

Is It Cushing's Disease, Kidney Disease or Both?

Kidney disease and renal failure can occur as a result of Cushing's disease or concurrently as a separate problem. Unfortunately, some symptoms of both diseases are the same, namely increases in urination and thirst along with lethargy. Your vet can give your pup blood and urine tests to determine which condition he is suffering from or if he's suffering from both conditions. She'll then set up a treatment plan for your pup, which will include either medication or surgery for his Cushing's disease, and medication or dietary changes for his kidney disease. Once the Cushing's disease is under control, other conditions, like kidney disease, should subside if they were caused by the excess cortisol in your pup's system.

The Possible Problems With Medication

Some medications approved to treat Cushing's disease in dogs aren't recommended for pups with kidney disease. The U.S. Food and Drug Administration has approved two medications to treat Cushing's disease in dogs, although some human drugs also are used with pups "off label." Trilostane is used mainly to control pituitary- and adrenal-dependent Cushing's disease in our canine companions, but shouldn't be administered to dogs with kidney disease, warns the FDA. Selegiline only treats pituitary-dependent Cushing's disease and doesn't normally affect your pup's kidneys. Consult with your vet regarding any medications used to treat his Cushing's disease, especially if Fido suffers from kidney issues, to avoid inducing kidney failure.