Piper, Max and Fifi were all scheduled for all day cushing’s tests Thursday. Piper and Fifi almost assuredly have cushing’s disease, but Max’s condition is a little weird. I want to make sure he doesn’t have cushing’s. Or at least, that I don’t miss it. Many of his symptoms could be explained by cushing’s.
Cushing’s disease or cushing’s syndrome happens because the adrenal gland secretes too much cortisol. The medical name is hyperadrenocorticism or literally over active adrenal gland in the cortical region.
Too much cortisol (or cortisone) causes an increase in appetite, increase in thirst, and therefore drinking more and peeing more. Lethargy, poor hair coat and dropped belly may also be seen. The pot belly is because of the increased belly fat and stretching of the abdominal muscles. Dogs can also have excessive panting, thin skin, chronic skin infections, dark spots on skin, skin mineralization and persistent bladder infections. Wounds tend to take longer to heal also.
There are three forms of Cushing’s disease. The most common is a pituitary gland tumor. The pituitary gland is located at the base of the brain. These tumors range from microscopic to larger. While both can wreak havoc on the adrenal gland, a large tumor inside the skull can lead to neurological signs. Big or small, the pituitary tumor tells the adrenal gland to produce more cortisol and does not listen to the signals that tell the pituitary gland that there is already plenty of cortisol. So there is too much cortisol.
The second cause of Cushing’s is an adrenal gland tumor. These can be benign or malignant in dogs. (In ferrets, they are almost always benign.) Because the tissue is a tumor, the adrenal cells produce too much cortisol and don’t listen to any signals. Instead of making more or less cortisol to meet the body’s needs, the tumor just pumps as much as it can.
The third type isn’t really a disease, it is a symptom. Iatrogenic cushing’s is caused by too much steroid given over too long a time period. Granted sometimes we have to give a lot of steroids (think autoimmune disease where the body attacks itself), but sometimes too many steroids are given for allergies or something where there are other options. Veterinarians often prescribe steroids on an alternate day dosage if possible so the adrenal gland can remain functional. Sometimes, owners don’t like the side effects of less steroids or decide that if a little is good, a lot is better. Iatrogenic (literally caused by medicine) cushing’s is fixed by a slow weaning off steroids or a management of less steroid dose.
None of these three had been given steroids lately, so an all day test was performed to confirm or deny the presence of cushing’s. Because treating a dog that dose not have cushing’s can be fatal, we have to have a positive test before treatment. The test consists of a baseline blood cortisol, medicine to lower the cortisol, time passage, more blood cortisol, drugs to raise the cortisol, more time passing and more blood.
We now have the ability to run these test in house, rather than send them out and wait two weeks for results. So Thursday was a flurry of drawing blood at exactly the right time, preparing samples and getting results. At the end of the day, Piper’s test was text book perfect for cushing’s. Max’s test results were strange. Too low when they were supposed to be high and yet way too high to be normal when they were supposed to be. (I decided to send his samples out to the endocrinologist.) Fifi’s mom said she didn’t want to do the test or medicate Fifi. Since she had at least three bloody band-Aids on her fingers from Fifi bitting her, I am fully on board with this decision.
Piper will start treatment while we hold off on Max and Fifi. Treatment is not an easy answer either. Piper and Max are both big dogs. Fifi is small. Unfortunately bigger dogs cost more to treat. I was shocked when I found that the new treatment for Piper or Max will be about $150 a month. This daily drug works by blocking the uptake of molecules to block the production of cortisol. The older treatment kills off part of the adrenal gland (in a very precise and somewhat dangerous way), but is only about $80 the first month and then $80 for the next six or more months. There was a third treatment for a while, but it is even more expensive and not as effective in most dogs.
So, Thursday may have had me running tests for cushing’s, but Sunday has me reading, researching and checking options so that I can guide the owners in the best possible way.