– Addison's Disease in the Great Dane –

November 24, 2003 – We've been discussing hypoadrenocorticism, or Addison's Disease, in the Great Dane. (See last week.) Addison's is not widely known to the general public and the condition is often misdiagnosed by veterinarians due to the fact that symptoms often mimic those of other diseases. In fact, Addison's Disease is often referred to as "The Great Pretender." While AD isn't exactly prevalent in our breed, it has a definite presence and you should know something about it because, if left undiagnosed, Addison's can kill your dog.

There are two basic types of AD: Primary Addison's (which is perhaps the easiest to diagnose based on symptoms) and Atypical Addison's. Each has its own characteristics and treatment protocol. To the lay-person, a discussion of the various clinical manifestations of the disease can get pretty complicated, as can treatment options. Unless your dog actually has Addison's, I don't think you need to know all that information, so I am not going to spend time talking about it. What's more important are the actual symptoms.

So, what are the symptoms?
Before we talk about the symptoms, you need to know that Addison's occurs in our breed and it is often misdiagnosed – or under diagnosed– by veterinarians. For that reason, Addison's may be more common than current estimates suggest. While AD may be difficult to diagnose based on observable symptoms, the ACTH (adrenocorticotropin) Stimulation Test can be administered to determine once and for all whether a dog has AD. This is a fairly expensive test, but it is the only test available that can provide a definitive diagnosis. If Addison's is identified as the source of your dog's problems, the disease is manageable, and he or she can be treated. However, for some families, the ongoing cost of treatment could be an issue.

You also need to learn to recognize the signs and symptoms of Addison's. Last week we read about Tank, who has Primary Addison's Disease. Tank experienced an acute Addisonian Crisis and nearly died. Prompt and knowledgeable medical attention pulled him through. He now receives regular treatment for AD and he is a happy, healthy dog. This week we'll read about Catherine, a seven-year-old Great Dane (pictured above) who has been living with Primary Addison's for 4 years. Like many AD-affected dogs, Catherine's symptoms were – at the onset – a bit confusing:

Tale of a "Near Miss" By Bobbie Marie Palsa Although a sudden, dramatic "crash," or Addisonian Crisis is not uncommon, many dogs experience a more insidious slide into Addison’s Disease. As the adrenal glands begin to fail, there is a waxing and waning of vague symptoms, often easy to miss or misdiagnose. Catherine's initial symptoms consisted of nothing more than a slight limp in her right hind leg and some generalized weakness in her rear end. She was originally diagnosed as having early arthritis from a sports injury, the result of rough-housing with our black lab. She was put on Rimadyl. At that time, Catherine had no other symptoms, but in retrospect, her unusually long hair-coat and her less than enthusiastic appetite hadn't been normal for months. After her first day on Rimadyl, Catherine's limping was resolved; however, her appetite rapidly declined over the next few days. This was worrisome. After four days Catherine was taken off the Rimadyl and our vet began running additional tests (blood, urine, you name it) to determine her problem. At that point her only 'clinical' indications were slightly elevated potassium and liver enzyme levels. By then Catherine's appetite was non-existent, although she never did go through the vomiting that so many AD dogs seem to experience. None-the-less, her weight had dropped 27 pounds and she had bloody stools. After consulting with Dr. Deborah Greco, one of the country's leading canine endocrinologists, our veterinarian ran the ACTH Stimulation Test. BINGO!! Catherine tested positive for Canine Addison's Disease. We got the results of the test on Saturday morning and she received her first injection of Percorten-v (DOCP) the following Monday. In the meanwhile, we were told to start giving her 30 mg of Prednisone a day to "prop her up" until she got her shot and the DOCP started doing its job. You can use an oral medication in a compounded dosage (an entire day's meds in one capsule) for about $30-$40 a month. The generic name is "fludrocortisone acetate" and it is generally prescribed at 0.1mg per 10 pounds of body weight – so a dog weighing 150 pounds would require 1.5 mg a day. Since the majority of the cost of compounded meds is the labor of putting the powder into the capsules, the price of this pretty much the same whether you're treating a 50 pound dog or a 150 pound dog! In other words, a month's supply of the compounded version of the brand name "Florinef" (which, btw, sells for about $1.25 a pill) would cost about a dollar a day to treat a 150 pound Dane with an entire day's dosage in one capsule – versus $15 a day for 15 individual "brand name" Florinef tablets. – Bobbie Our vet later told us that Catherine's initial symptoms – limping and generalized weakness of the rear quarters, depressed appetite, and unusual coat – were due to underlying Addison's Disease. Upper gastrointestinal irritation, ulceration and bleeding is consistent with Addison's. In Catherine's case, the Rimadyl and high doses of Prednisone administered prior to her first DOCP injection resulted in extensive damage to her stomach. So even though her electrolytes were stabilized within hours of her first DOCP injection, Catherine's stomach was still in very bad shape. Four days after her first treatment, Catherine collapsed and was admitted to the ER in shock. At least by then all they had to focus on was controlling the upper GI bleeding by "spackling" her stomach with Carafate, then transfusing a unit of blood and rehydrating her. For about a month after that, Catherine took Carafate and Pepcid on a regular basis. Once she got over the hump and her stomach began healing, Catherine's appetite returned to normal. After two months of treatment she was BETTER than her "old self" and started regaining the weight she had lost. For the first few months after Catherine's initial diagnosis, we ran blood work once a month. Now we check her electrolytes once every three or four months. Catherine has remained rock-solid and stable for almost four years! The only time her limping and hind-end weakness returned was four months after her first injection of Percorten-v (DOCP). That's because her original DOCP dosage, which was calculated based on her initial body weight, was no longer adequate. Once the dosage was adjusted to compensate for her weight gain, Catherine was fine again. The timing from Catherine's first exam (for limping) to her final diagnosis of Addison's Disease was less than three weeks, but it seemed like forever! When the results of the ACTH test came in, the vet told us: "The good news is that it's completely treatable. The bad news is that it's extremely expensive." We focused on the GOOD news. And we've since discovered that there ARE some less expensive treatment options – if you know where to look. Today our girl is a happy, goofy, active, squirrel-chasing seven- year-old with a healthy appetite for food – and life in general! Nobody'd better ever tell HER she's got a *disease!* She's got at least another seven years to go. After all, there are a lot more squirrels in them thar trees! There's a wealth of information on Canine Addison’s Disease at www.canineaddisonsinfo.com. We were lucky that Catherine didn’t go into a full-blown Addisonian Crisis or "crash" before she was diagnosed, but many dogs aren't as lucky, and many don’t survive. Having your dog diagnosed early and correctly is half the battle, the other half is finding a vet who – if he’s not already familiar with AD – is at least willing to learn about it along with you. Maintaining a stable Addisonian is basically simple: you replace the hormones their failing adrenals can no longer produce. When you first hear your dog's been diagnosed with Canine Addison's, it's a lot easier to wade through the "information overload" with the help and support of over 1100 members at K9 Addisons, a Yahoo mail list forum. – Bobbie Marie Palsa

Symptoms of Primary AD
Dogs with Primary Addison's Disease often exhibit gastrointestinal problems, such as loss of appetite, vomiting or diarrhea. They can appear weak, easily fatigued, and depressed. They may also exhibit a generalized weakness in their hind quarters and/or they may limp. Their fur can be affected in a variety of ways, too. Some dogs may develop a thicker coat, while others may lose fur. Some dogs might even develop a curly coat – or lose the curl they've always had.

Every dog is different, though, and there is no "absolute" set of symptoms. Still, as you read first-hand accounts of the disease, a pattern begins to emerge.

Cynthia had this to say about her Dane, Lily, another Primary AD patient:

The first thing I noticed about the onset of Lily's AD was that she had difficulty supporting herself with her front legs in a sitting position. I didn't really think much about that until she started to really get sick. She stopped eating-totally. I went nuts doing things like cooking a big pan of chicken for her and she just turned away when I offered it to her. Of course, we were back and forth with the vet and he kept zeroing in on Wobbler's but that really didn't make sense, either.

As her disease progressed, she bled from her mouth and her gums were very red instead of the normal blackish color. She also wasn't able to lift herself from a lying position. Within a few weeks of her initial symptoms, Lily had lost a total of 40 pounds. At this point the vet sent us to the University of Georgia vet school. They were wonderful. What had seemingly been an undiagnosable situation here in Charlotte, NC, the people at vet school in Georgia nailed in a matter of hours. Once Lily began medication she immediately improved and in a short time she was completely normal.

Merrell writes about OP:

OP, our harle, was diagnosed with Addison's Disease earlier this year. His first symptom was that he would just stop and lay down on our daily walks. Then he had trouble getting off the couch. (Yeah, I know, tough life, eh?) We were treating him for a bad back. His coat, which is abnormally thick and curly to start, got even more weird, spotty and shaggy with unbelievable shedding. He looked like a Shetland pony with a bad hairdresser. He was tired and depressed and thirsty. We were traipsing from veterinary specialist to veterinary specialist, both holistic and allopathic. I kept telling them that "something is just off." To me, the most frightening thing about Addison's disease is that the symptoms are so nebulous. I strongly feel that Addison's is under-diagnosed.

Marilu writes about Cissie:

My Dane Cissie was diagnosed with Addison's 5 years ago at the age of 4. Prior to finally being correctly diagnosed, she had had many bouts with pimples on her chin and neck area and had several biopsies of that area. She also went thru a period of horrendous shedding. I thought she might actually go bald. Her appetite has never been what I consider Dane-like, and throwing up was the norm for her.

Since being diagnosed and stable on her DOCP injection and daily Prednisone, Cissie has no more pimples, no excessive shedding and she is a much better eater. Had I not found the right vet, she would have died years ago and I would have missed out on a lot of the joy that just living with her brings me.

Sarah writes about Summer:

Thanks for bringing up the Addison's issue. Summer, my 3-year-old harle, was diagnosed when she was one and a half. My husband and I had gone on a short trip and left her at a boarding kennel (which had been highly recommended). When we picked her up 5 days later, she looked horrible. The worst part was that she didn't seem to recognize us, or care that we were back. We knew something was wrong and took her to our vet. She had several episodes of diarrhea and her fur was dull and shedding. When we got to the vet, Summer wouldn't get out of the car and growled at the vet when we tried lift her. (Summer loves the vet!) Luckily, our vet decided we should immediately go to the University Vet School after she was started on fluids. They recognized the signs of Addison's Disease. They told us how close we were to losing her. She had lost 16 lbs during the 5 days we were gone! She is doing great now on her Prednisone and monthly injection.

These dogs were all lucky because their AD was diagnosed and treated before they went into a full-blown Addisonian Crisis. During an Addisonian Crisis, a dog may collapse, go into shock, have a slow or irregular heart rate, low blood pressure, and show signs of what appears to be (but is not) acute renal failure. If inappropriately treated, it is likely the dog will die.

The next installment...
Next week we'll wind things up by taking a look at Atypical Addison's. This condition can be even trickier to diagnose based on symptoms alone. We'll also talk about how you or someone you know might be able to participate in a research project to explore the genetics and heritability of Addison's Disease in the Great Dane. And in conclusion, I'll provide a comprehensive set of links to Canine Addison's Disease resources. (See next installment.)

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