Neurological Symptoms Can Be Misleading

Two years ago, a simple case of what was believed to be dew poisoning on my horse’s hind legs left behind a bizarre small spot on the back of the fetlock. The spot simply wouldn’t heal.

The hair fell out in that area, and there was heat and swelling. The spot started out the size of a nickel and gradually grew until, two years later, it was the size of a golf ball and inflamed. Little did I know then, this may have been a bite from a tick carrying Lyme disease that eventually forced me to retire my beloved mare. (Note: Skin reactions/rashes are often noted in people who are bitten, but it’s the exception rather than the rule to have this obvious of a deer tick-bite site on a horse.) Seven veterinarians examined my 12-year-old mare, Sneakers, including an equine dermatologist. Biopsies showed nothing. Ultrasounds were negative, and a 60-day course of sufla antibiotics was no help.

The hairless lump became a curiosity. No one had seen anything like it. At times, it appeared just cosmetic, but in reality the entire fetlock was inflamed. Sneakers would stock up in the stall, but exercise would reduce the swelling somewhat. I was able to trail ride and foxhunt occasionally, but lameness issues were always present.

As time went on, Sneakers began to drop out on the hind end. We attributed it to weak stifles, and she became progressively worse. One spring morning, we both fell while cantering. I have no recollection of the fall as I received a severe concussion — and I wouldn’t be here today if it weren’t for my ASTM/SEI helmet. According to relatives watching us, Sneakers’s hind end simply went out from underneath her.

Two weeks later, she almost went down again, this time on a longe line. Something was definitely wrong, but I naturally suspected a lack of conditioning. I began a program of cavalletti and hill work to strengthen the hind end with lots of trotting.

At that point, my husband and I were transferred to Richmond, Va., and I found a beautiful facility with wonderful old friends to take care of Sneakers. The new veterinarians tried injecting her hocks for the hind-end weakness. No change. We wrapped the back-ankle lump for 30 days with simple triple antibiotic cream, which resulted in some hair growing back but the inflammation and lump remained. We also tried Azium powder, a corticosteroid to help control inflammation, to no avail.

One night at the barn, I began talking with a woman, who happened to be a veterinarian waiting for her daughter to finish a lesson. As we talked, one thing led to another and I told her about Sneakers. The vet examined her back ankle and then did a few simple tests, which I now realize were neurological.

Sneakers couldn’t walk down a small embankment without buckling. The “tail pull” test was also positive for neurological dysfunction. The vet suggested that I take her for an EPM (equine protozoal myelitis) test.

My heart sank. I heard that EPM was regularly diagnosed whenever neurological signs were spotted. The gossip trail about EPM was that it was “heavily overdiagnosed” and the spinal tap test can sometimes result in a false positive. On top of it being a serious disease, it was also extremely expensive to treat.

Contemplating the diagnosis and potential expense, we decided to rule out any other complications that could be making her buckle, such as pain and locking stifles. We put her on bute for a week, which helped a great deal. There were no signs of “dropping out” on the hind end when she was longed. However, when she walked down a small hill she still buckled. (Note: The bute was controlling the joint inflammation, so some of the buckling was indeed pain, not neurological, but not all of it.)

We decided if we blocked the stifles, kept her on the bute, took away as much pain as possible and then walked her down a hill, it would be the true test. Blocking the stifles made no improvement. I broke down in tears. She looked like a million bucks, but it was so deceiving.

I realized I couldn’t continue to ride her. Someone suggested that I donate her to a veterinary school, which I considered, thinking it might help some new vets learn from her and prevent other horses and owners from going through the same horror.

The following week, Elaine, a sales clerk at a local tack shop, asked how Sneakers was. I choked back and told her what was going on. She was so compassionate. We discussed possible homes for Sneakers in the area, including a nearby equine reproduction facility. Then she recalled a small-animal veterinarian at Montpelier Veterinary Hospital who was looking for a pasture mate for his horse. He said that he would even take a horse that has EPM. This was too strange. Why would someone want to take on that’

It was obvious that I had to deal with the situation, so I called. Dr. Jerry Bayer was interested, so we arranged a time for him to visit Sneakers the following week. We chatted at length, and I learned he was a foxhunter as well. We had a lot in common and, to my relief, he agreed to take her. Jerry said he noticed the hind-end lameness issues, but he didn’t comment a whole lot. He did say that he planned to do some blood work. Sneakers would have a good home with a vet.

Two weeks later, after going through the emotional turmoil of retiring Sneakers, I called Jerry to see how Sneakers was doing. He said she was getting along fine with her new friend, a big Clydesdale/Thoroughbred cross named Woody.

In addition, he had just received the blood work results. My heart sank as he read the result: Lyme disease. Sneakers was off the chart for the disease. The symptoms are similar to EPM, with neurological difficulties but also joint inflammation. I thought about the persistent lump on her hind fetlock.

Unfortunately for Sneakers, the fact that the levels were so high in her blood indicated that she had the disease for quite some time. Chances of a full recovery were reduced due to the length of time she had been infected, and there was likely permanent neurological damage. However, it all began to come together — that’s why her hind end was going out from underneath her. That’s why we both fell down a year and a half ago.

The good news is there is a treatment: oral Doxycycline. This treatment is far less expensive than treating for EPM. However, Lyme disease, like EPM can be difficult to treat.

When I told friends, many expressed disbelief that horses could get Lyme disease. Others thought the disease was only in northern states. I remember several specific bouts with ticks that Sneakers had, but Lyme never occurred to me or the other vets who helped me.

Sneakers was treated with oral Doxycycline at 9,000 mgs per day (4,500 mgs in the morning and 4,500 mgs in the evening) for 28 days. How effective the course of treatment was remains to be seen. Because she likely has had the disease two years, a full recovery is not expected, but she has wonderful new home.

Also With This Article
Click here to view ”Kit And Sneakers.”
Click here to view ”What Can You Do’”
Click here to view ”Tick Proofing.”

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