Canine Cushings Disease Diagnosis

Canine Cushings Disease, or hyperadrenocorticism, occurs when the adrenal glands produce excessive amounts of glutocorticoid in the body or the pituitary gland excretes too much ACTH. Canine Cushing’s Disease can cause a whole host of problems for dogs and can usually be resolved with the help of surgery or medication.

Symptoms of Canine Cushing’s Disease

Canine Cushing’s Disease can present itself in many ways. If your dog has canine Cushing’s Disease, you may notice an increase in his appetite and water consumption and therefore, he may urinate more. He may experience hair loss and thinning of the skin. In addition, his abdomen may appear enlarged, a symptom which effects about 80-percent of those with canine Cushing’s Disease. 

Diagnosis of Cushing’s Disease in Dogs

If you suspect that your dog may be suffering from canine Cushing’s Disease, take him to his veterinarian to have tests performed. A dog who is suspected of having canine Cushing’s Disease should have a complete blood count, chemistry panel and urinalysis run for preliminary testing. Abnormal values, such as increased alkaline phosphatase, cholesterol and ALT, decreased BUN levels and dilute urine are all clues that your dog has canine Cushing’s Disease and should have further testing.

A urine cortisol/creatinine ratio is helpful in diagnosing canine Cushing’s Disease. Typically, the pet owner collects the sample of urine while the pet is at home—that way, the pet is not stressed. The doctor will send the urine out to a lab and, if the results are abnormal, it is likely the dog has canine Cushing’s Disease. However, because other diseases can cause abnormal results, more testing should be done to diagnose that it is indeed Cushing’s Disease.

The next step in diagnosing Cushing’s Disease is performing a low-dose dexamethasone suppression test. This test works by administering a low dose of dexamethasone to the canine and pulling blood eight hours later to see how the body reacts to the drug. Normal dogs show a decreased amount of blood cortisol levels, while those with canine Cushing’s Disease do not. Additionally, performing an ACTH stimulation test can also be helpful in diagnosing Cushing’s Disease.

Performing an abdominal ultrasound can also be helpful in many ways. Not only does it let the doctor know if there are any abnormalities among the abdominal organs, but the veterinarian can examine the adrenal glands, as well. If the dog has pituitary-dependent Cushing’s Disease, the adrenal glands will appear either normal in size or larger. If the Cushing’s Disease is caused by a tumor, one gland will be larger or uneven in shape. Furthermore, if a tumor is detected, the doctor can try to see if it has spread to other organs. 

Treating a Dog with Cushing's Disease

There are a variety of methods in which to treat Cushing’s Disease in dogs. If a tumor is present on the adrenal glands, surgery to remove it may be an option. The most popular method of treating canine Cushing’s Disease however, is through medication. Most veterinarians prescribe the drug Lysodren, which works by destroying the cells in the adrenal gland that are responsible for producing corticosteroids. Another option is the drug Trilostane, which is effective but more expensive than the Lysodren.