Canine Cushing's disease (Canine Hyperadrenocorticism) can either be connected to steroid treatment or to a microscopic pituitary or adrenal tumor that occurs in middle-aged or older dogs. This disease is also common in animals that have been diagnosed with diabetes and pancreatitis, because Cushing's disease involves the production of cortisol, which affects the production of insulin.
Symptoms of the disease are usually noticeable. The dog will have an increase in thirst, leading to an increase in urinary output and in urinary accidents in housebroken pets. Accompanying this increase in thirst may be an increase in hunger, leading to weight gain.
Physical changes are commonly seen as well. Often, he will develop a noticeable pot-belly that is saggy and bloated. He may have a loss of muscle and his head will be bony and skull-like in appearance. It's common for the dog to become lethargic as well as reluctant to jump on furniture. You may notice other health problems such as excessive panting, hair loss, a duller coat and increasingly fragile skin. There may also be seizures and a susceptibility to infections. Always make sure you provide the best possible dog health care to your pooch. Have a trusted vet nearby so you can ask all your questions as soon as possible.
When a dog exhibits a combination of these symptoms, he should be carried to his veterinarian who will diagnose the problem:
- The vet will perform a physical exam, looking for physical symptoms.
- Blood tests will be taken, which could show a rise in liver enzymes, cholesterol and blood glucose -- all signs of this disease.
- The vet may order urinalysis, which could show high levels of protein in the urine.
- Diagnostic work may also include X-rays or an ultrasound to look for an enlarged liver, enlarged adrenal glands or atrophied adrenal glands.
Your vet will determine a proper treatment route based upon the dog's overall health and the type of Cushing's disease -- adrenal, pituitary or iatrogenic.
- Surgery may be considered a good option if the disease is caused by an adrenal gland tumor. This tumor will be removed along with the affected adrenal gland. If the disease is caused by a pituitary gland tumor, no surgery will be recommended because these tumors are tiny, grow slowly and the only damage they do is to overstimulate the adrenal glands.
- Radiation is considered for pituitary macroadenomas, or pituitary tumors, to reduce their size and relieve any neurological symptoms. This treatment is very expensive and requires the use of anesthesia.
- If Cushing's disease is iatrogenic, then treatment will include stopping the use of the cortisone causing the condition. This discontinuation must occur slowly. The reason for the cortisone being prescribed may reoccur, causing more problem. This condition may also cause damage to the adrenal glands that could require treatment as well.
- Drug therapy is used for treating both types of tumor.
- Lysodren is a drug administered once or twice a week for the remainder of the dog's life. This drug has side effects such as appetite loss, vomiting, diarrhea, muscle weakness and lethargy as well as Addison's disease, which causes the cortisol levels to drop below normal levels.
- Ketoconazole is given to dogs that cannot tolerate Lysodren. Ketoconazole is an expensive oral antifungal medication given daily. The only side effect of this medication is suppressing hormone production.
The prognosis for dogs diagnosed with Cushing's disease depends on whether or not treatment is given.
- If no treatment is administered, the prognosis is poor, and the dog generally dies.
- If treatment is administered, the symptoms will go away completely in 4 to 6 months. Excessive drinking and eating are usually the first symptoms to disappear. After proper treatment, the dog can live many more years.