Dear Daisy Dog
My dog was just diagnosed with Cushing's disease. What can you tell me about this disease?
Cushing’s disease, or hyperadrenocorticism, is caused by overproduction (hyper) by the adrenal gland (adreno) of the hormone cortisol (corticism.)
The most common signs are excessive thirst, urination and appetite.
Some of my dog friends have been yelled at for messing in the house, but they couldn't help it because they had Cushing's disease and their people didn't know it.
Other signs are panting, thin hair, poor skin quality and a pot-bellied appearance due to an enlarged liver and thin abdominal musculature.
Cortisol may be produced in excess for one of two reasons: 1) the pituitary gland at the base of the brain may produce excessive ACTH (adrenocorticotropic hormone) which tells the adrenal glands to produce too much cortisol, or 2) one of the adrenal glands may work independently to produce too much cortisol.
In 85% of dogs, the pituitary is at fault. The remaining 15% of cases are due to a mass on the adrenal gland. Half of these adrenal masses are malignant, and half are benign.
Sometimes the first clue is found on routine bloodwork: an elevated alkaline phosphatase occurs in 80% of dogs with Cushing's disease. Because excessive cortisol suppresses the immune system, your dog may have recurrent infections – another clue.
Diagnosis is made using blood tests specific for Cushing's disease and sometimes by abdominal ultrasound.
Treatment options are medication to control the disease (Lysodren or Anipryl) or surgery to remove an adrenal tumor. Follow-up is important, especially for dogs who receive Lysodren.