Courtesy of:  Dr. Michelle

Our last Facebook contest gave you the opportunity to guess what disease our 12 year old fictional dog Sparky had.  The correct answer was Cushing’s Disease (also known as hyperadrenocorticism, or HAC).

HAC is a disease involving an excess of one or more adrenal gland steroids, most commonly cortisol.  We tend to see this disease most commonly in older dogs over 6 years of age.  There are many clinical signs to watch for including: drinking more than normal and therefore urinating more than normal (which can also be a sign of diabetes or kidney disease), excessive hunger, a distended belly, panting, thinning or loss of fur, and oily skin.

In order to diagnose HAC, we start with some basic blood work.  The most common finding of these tests is an elevation of alkaline phosphatase (ALP).  This enzyme, which is normally found in the Iiver, may be elevated in either liver disease or when there is an excessive amount of steroids in the bloodstream (as is the case in HAC).  The next step in the diagnosis of HAC is to do one of two tests: an ACTH stimulation test or a Low Dose Dexamethasone Suppression test.  Depending on the clinical signs and blood work results of the individual dog, the doctor may choose to do either of those tests.

Once a diagnosis of Cushing’s disease is made, treatment will be started.  The most common treatment is a pill called Trilostane (Vetoryl).  This drug inhibits cortisol production at the level of the adrenal gland, therefore reducing clinical signs associated with the disease.  There are also drugs which partially destroy the adrenal gland and are only indicated in certain cases of HAC.  Other more drastic treatments such as surgery or radiation therapy may be needed in very rare instances.

After beginning Trilostane, a follow-up ACTH stimulation test is performed one month later, and the dose of the medication is adjusted as needed.  We recommend repeating an ACTH stimulation test every 3 months to make sure that the cortisol level in the dog is not dropping too low which can lead to an emergency condition called an Addisonian crisis.

Dogs can live a long and healthy life after being diagnosed with HAC.  If your dog is experiencing any of the symptoms that Sparky was showing, please give Truro Vet a call at 893-2341.