Hypertrophic Osteodsytrophy in Weimaraners

Over the last few years, there’s a story I’ve heard many times. A dog owner will send me an email telling me about the time their puppy became ill with a disease called hypertrophic osteodystrophy.

One afternoon Bix developed diarrhea. Along with that was a fever of 105°F… the following day this puppy was screaming in pain every time he moved or was touched.

People reach out to me because I’ve written about our experience with the disease on my blog, Urban Dog. Our Weimaraner, Bodhi, came down with hypertrophic osteodystrophy, or HOD, when he was about three months old. The following six months were very difficult, but, as you will learn below, there is a path to a happy outcome. With the help of Dr. Noa Safra, a geneticist, veterinary clinical pathologist, and Weimaraner owner, we were able to manage the disease, and, I don’t think I’m being too hyperbolic, to save our dog’s life.

What is Hypertrophic Osteodystrophy?

Hypertrophic osteodystrophy is an autoinflammatory disease that affects rapidly growing puppies. Inflammatory disorders are diseases where the immune system attacks the body’s own cells or tissues and causes abnormal inflammation. Mild cases can last a few days; more serious ones can last for months. In the very worst cases, the puppy may need to be euthanized. If you’ve heard anything about it, you’re probably aware that it primarily affects a puppy’s bones. In particular, it targets the bone’s growth plates, the softer parts of the bone where growth occurs. The symptoms of the afflicted limbs are lameness and bone pain.

While HOD mostly affects puppies’ bones, there can also be many other symptoms. They include high fever, discharge from the nose and eyes, lack of appetite, diarrhea, bloody stool, sounds in the lungs that can indicate disease, pneumonia, skin pustules, and vaginal discharge. At the time we didn’t know it, but Bodhi’s first symptom wasn’t associated with his bones, it was diarrhea. And during the course of the disease he experienced almost all of the above symptoms at one point or another.

And if that list weren’t enough, there’s one aspect about HOD that can be particularly difficult to deal with: it can often recur. Puppies may suffer many flare-ups of the disease until their growth plates harden and the bones stop growing. Recurrence of the condition can happen until the puppy is eight-to-ten months old, but in extremely rare cases it can recur after 24 months. Managing flare-ups was in many ways the most challenging part of dealing with Bodhi’s disease.

Hypertrophic osteodystrophy has been identified in forty different dog breeds, as well as in mixed breed dogs. Certain large breed dogs appear to be predisposed to getting the disease: Great Danes, Boxers, German Shepherd Dogs, Irish Setters, and Weimaraners.

Weimaraners and Irish Setters seem to be the dogs that suffer worst from it.

The cause of hypertrophic osteodystrophy is unknown. There is evidence to support a genetic component to HOD, and the current thought is that this component is widespread in Weimaraners. Why some pups suffer from HOD and others don’t, likely reflects a complex interplay between inherited and environmental factors. There are many possible triggers to HOD. It has been suggested that vaccinations or a stressful event are among those triggers, but there’s currently no conclusive evidence to support this.

Diagnosis and Treatment

Veterinarians diagnose HOD on the basis of medical history, clinical signs, and by ruling out infectious causes. The most important diagnostic tool is taking radiographs, a type of X-ray. Radiographs can show the typical bone lesions that form in connection with HOD.

There is no cure for hypertrophic osteodystrophy. Afflicted dogs receive treatment for their symptoms: alleviating pain, controlling fever, as well as managing any of the other symptoms that may occur.

Vets routinely treat HOD with non-steroidal anti-inflammatory drugs (NSAIDs.) This is what was prescribed for Bodhi when he was first diagnosed. NSAIDs work for most dogs, but unfortunately, many Weimaraners do not respond well to this type of treatment. Bodhi is one of those Weims. His first round of treatment seemed to work, but a few short weeks later he relapsed. His second flare-up was much, much worse than the first, and the NSAIDs did nothing to alleviate his symptoms. It was at this point that our veterinarian used the treatment regimen developed by Dr. Safra. She advises using Prednisone, a corticosteroid, rather than NSAIDs. Afflicted puppies should also receive antibiotics and Pepcid (the Prednisone can cause stomach issues.) It’s very important for vets treating Weims (and Irish Setters) to know about Dr. Safra’s work. Valuable time can be lost if they are treated with NSAIDs.

The next step is to manage the use of the Prednisone. It is a very strong drug and if your puppy is taken off of it too quickly, there can be side effects. This is where the really frustrating part of HOD comes in: your dog will start to get better, the dose of Prednisone will be lowered, but then there’s a recurrence, so it’s back to a higher dose. It’s a tricky game of start and stop until the illness has run its course. Eventually though, your pup can be weaned off the drug.

Most cases of HOD, approximately 70 percent, are not as difficult to manage as Bodhi’s. His was an extremely severe case; Dr. Safra rated it a “nine” on a scale of “one-to-ten.” But even though he had a rough go of it, Bodhi made it through and today enjoys a normal, healthy active life style as an adult. His legs didn’t grow in fully, he’s probably a good five inches too short for an adult male Weim, but he certainly doesn’t seem to notice! And that’s all that matters!

For more details about Dr. Safra’s work visit PubMed Central (PMC) a free archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health’s National Library of Medicine. There you will find a very technical document, but if your veterinarian is looking for a peer-reviewed paper on hypertrophic osteodystrophy and Dr. Safra’s recommended treatment for Weimaraners, that is the place.

For a more personal account of our success story with the disease, read “Bodhi’s Story” at Urban Dog.

We also have two other personal accounts: “Buddy’s Story” and “Bix’s Story.” They are password protected. If you want to read them contact me at sean.sheer@theurbandogshop.com and I’ll provide you with links and the password.

Editor’s Note: Please also see the Weimaraner Club of America’s article on HOD.