Q: Our dog has recently been having some issues such as drinking and urinating a lot. She also has been having issues getting around, which we thought was from arthritis, since she is now 10 years old. Our veterinarian ran some blood work on her and she said that she needs to do some additional testing because our dog may have Cushing’s disease. What exactly causes this and what is her long-term prognosis if she does have Cushing’s?
A: Cushing’s disease is typically caused by a benign tumor from the pituitary gland that then stimulates the adrenal glands to secrete excess hormones, mainly cortisol. Cortisol is the body’s natural form of cortisone that it secretes to help with multiple daily functions, especially such things as the flight or fight response that your body has in reaction to fearful or emergency-type situations. So cortisol is normally a good thing, but in excess can be a very bad thing for your dog’s health. It will cause excess drinking and urinating, possible hypertension, and a general loss of muscle mass and strength over time.
Your veterinarian is correct in that additional blood tests are needed to confirm a diagnosis of Cushing’s disease. If after these tests, your veterinarian has confirmed Cushing’s, there are a couple of different medications that can be used to “shrink” the adrenal glands so that less cortisol is produced. The key is finding just the right amount of medication so that it reduces the production of cortisol, but doesn’t stop it completely.
Long term, your dog should have a decent prognosis, but her life span will possibly be shortened at least a little bit. In my experience, the average dog that is treated properly will live for an additional two to three years after diagnosis. Just be aware that she will have to have periodic blood tests done and remain on medication for the rest of her life.