Without treatment, Cushing's disease puts a dog at higher risk for developing diabetes mellitus, bladder stones and potentially fatal blood clots. A dog's overall prognosis depends on what kind of Cushing's disease he has. Cushing's disease usually strikes older dogs. Prompt treatment can give a dog a chance to live close to a normal life span.
Formally known as hyperadrenocorticism, Cushing's disease results from excess cortisol hormone production. Produced by the adrenal glands, cortisol affects many bodily functions, so Cushing's has a wide range of symptoms. The disease is caused by either a pituitary gland tumor, an adrenal gland tumor, or overuse of steroids. The latter usually occurs during the course of treatment for another medical condition and is known as iatrogenic Cushing’s disease.
If your older dog starts drinking copious amounts of water and urinating frequently and develops a ravenous appetite, Cushing's disease could be the culprit. Many dogs suffering from the disease develop a classic "pot-bellied" appearance, along with a poor hair coat. Other symptoms include lethargy, frequent skin infections, hair loss, bruising, skin darkening, shortness of breath and urinary tract infections.
Your vet will perform various blood tests and a urinalysis on your dog, along with a physical examination, to diagnose Cushing's disease. She might ultrasound your dog's abdomen to see whether an adrenal gland tumor is present. Treatment depends on the type of hyperadrenocorticism. For pituitary tumors, which are usually benign, your vet prescribes medication which your dog must take for the rest of his life. Adrenal gland tumors are usually surgically removed. In cases of iatrogenic Cushing’s disease, dogs are slowly weaned off the steroids.
A dog whose Cushing's disease results from a benign pituitary tumor or an adrenal tumor, a dog might live for years with treatment. If either type of tumor is malignant, the outlook isn't that favorable. For dogs with iatrogenic Cushing's, much depends on the underlying disease for which the animal received steroids. The U.S. Food and Drug Administration website says a dog with Cushing's disease "can live a good life" as long as he's monitored closely by a vet and his owner is diligent regarding bringing the dog in for regular blood work and administering medication.