Diagnosing Canine Addison’s Disease

Jenny Wang knew something wasn’t right with her German Shepherd, Bo. Bo’s usually spunky temperament had turned to listlessness. “Her eyes had just lost her spark,” Jenny said. Sometimes she would notice Bo had trouble walking or getting up onto the couch, but the symptom would appear and then disappear for days. eventually, Bo lost her appetite, ignored her dinner and had diarrhea. Jenny started looking at Google for answers but found an overwhelming amount of information. “Diarrhea, vomiting and listlessness could have come from a dozen or more illnesses. “I thought perhaps she’d got into some poison, but I had no way of knowing. My vet initially diagnosed her with inflammatory bowel disease.”

Addison’s disease is named after the 19th century British physician Thomas Addison who reported thed adrenal gland dysfunction in 1849. Sometimes called hypoadrenocorticism or adrenal insufficiency, Addison’s disease is fatal without treatment.

After Bo’s health began to deteriorate again, Jenny sought help from a new vet who immediately suspected Addison’s disease. Twenty-for hours later, the diagnosis was confirmed and Bo is now in good health.

The Signs and Symptoms of Canine Addison’s Disease

Signs and symptoms vary dramatically between dogs, so you should also take into account the following questions when trying to determine if your dog might have canine Addison’s disease:

• Is your dog experiencing any of the following symptoms? blood in vomit, changes in coat, which may become thicker, thinner, longer, or curly, dark, tarry stools, depression, diarrhea, excessive urination, hind-end pain, increased thirst, listlessness, loss of appetite, muscle or joint pain, muscle weakness, painful or sensitive abdomen,
  shivering, tremors, vomiting, or weight loss.
• Has your dog suddenly taken very ill with multiple symptoms? If so, this could be an Addisonian crisis — it is a medical emergency and you should take your dog to a veterinarian immediately. If not treated, an Addisonian crisis can kill within hours.
• Is your dog female? (Females are more likely to be affected’ about 70 percent of cases are female).
• Is my dog around 4 to 6 years old? (Although canine Addison’s disease can affect younger and older dogs, 4 to 6 is the median age.
• Is your dog one of the following breeds? Airedale Terriers, Basset Hounds, Bearded Collies, German Shepherd Dogs, German Shorthaired Pointers, Great Danes, Labrador Retrievers, Leonbergers, Nova Scotia Duck Tolling Retrievers, Poodles, Portuguese Water Dogs, Rottweilers, Saint Bernards, Soft Coated Wheaten Terriers, Springer Spaniels, or mixes of these breeds? (These breeds are more susceptible to canine Addison’s disease).

In addition to the above signs, the following list of symptoms might be more likely to be seen upon examination by a veterinarian: dehydration, low blood pressure, low body temperature, mental depression, muscle weakness, pale mucous membranes, patches of darkened skin, slow and weak pulse, and a thin or emaciated body.

Blood tests may reveal: anemia, elevated BUN and creatinine, elevated liver enzymes, elevated potassium, high calcium, low cholesterol, low glucose, low protein (albumin and globulin), low sodium and metabolic acidosis. Note: a sodium/potassium ratio of less than 27 is a strong indicator of Addison’s disease. Howver, a normal ratio does not rule canine Addison’s disease out.

The ACTH Response Test

The ACTH response test is used to diagnose canine Addison’s disease. Your dog’s cortisol level will be measured, then your dog will receive an injection of ACTH. One hour later, a blood sample will be drawn and cortisol measured again. Canine Addison’s disease is confirmed if there is no change in cortisol levels.

Misdiagnosis

Dogs breeds originating around the Pacific rim, including the Akita, Jindo and Shiba Inu, are often found to have elevated potassium values, which can lead to a misdiagnosis. In addition, whipworms can cause low sodium and elevated potassium. Eggs from whipworms are shed infrequently, leading to a possible negative result on a stool test. However, in both situations, the ACTH test will be normal, which is why the test is a must before beginning treatment.