Testing for EPM

[Lone]

My mare has been having some very mysterious lameness problems since Oct. We've done a bone scan, x-rays, untra-sounds, nerve blocks, etc and haven't made much progress.

We tested her for Lyme disease, got the results back today that she was negative. Next up we're testing her for EPM. Most of what I've found online talks about doing a spinal tap to test for it? My vet suggested that we just draw blood to test (cheaper and easier). Any thoughts on that? Will it be as accurate?

Thanks for the help.

[2horseowner]

I did the blood test, which came back positive. When the vet pulled the blood, she also did some neuro tests. These give you an idea about the horse's balance. Mine passed those w/ flying colors. The big issue for mine was the incredible muscle wastage along the top line and hindquarters. He looked awful and felt depressed. You must know that EPM presents in many different ways. If I had known better, I would have treated for this instead of ulcers. I only saw a slight improvement from that. You have the feeling your horse is just not quite right. The spinal tap can be iffy. You may or may not get a good sample, and the horse needs to be under to do so. High $$$ on top of the Marquis medication. I did 2 months of Marquis, by the third week, major improvement. All cases are different. Some horses get worse before they get better. I went w/ the blood test because I did not want to put my horse through a spinal tap. He is now back in full work and doing great. I know this is a tough disease to face, don't wait too long to treat if needed. Talk w/ your vet, and good luck.

[smay]

The thing about the blood test is that many horses will test positive for EPM but not show any symptoms of disease, due to being exposed to it. So it's more of a confirmation test after ruling out other neurological diseases when a horse shows symptoms. If all other tests are negative, horse shows symptoms, and EPM blood test comes back positive, often vets will recommend treating with Marquis without going to a spinal tap, just to see if it "works." It's an expensive "if" but some horses do show a remarkable improvement on the medicine.

[lionstigersbears]

When my horse was tested for EPM I was told, like Smay said, that most horses have been exposed to it and therefore test positive in blood work. I had my horse spinal tapped, they do not need to be put under if the tap is done near their dock, unfortunately they tried that area for my horse and were unable to get a sample, asked me and I agreed to have him put under to have the tap done from near his poll. He came through the procedure fine (and tested positive).

The thing is, even with the spinal tap, the results are not 100% accurate, and just because a horse tests positive does not mean that they are showing symptoms of EPM since there is no definite to test for it.

There are a lot of articles about EPM on Equisearch and one contributor, Jayne Pedigo, wrote about her experience with EPM in her horse Annapolis. Here is a link to one of those articles ("Should you test for EPM"), but you can do a search on Equisearch or just in google (EPM equisearch) and find all the others:

http://www.equisearch.com/horses_care/health/illnesses_injuries/eqepmtest310/

[Lone]

Thanks everyone.

My mare isn't showing the 'typical' symptoms with the lack of coordination etc, which is why we've waited so long to test. But from what I've read it can show up in many different ways depending on the horse.

[Tutt]

A couple years ago, researchers developed a much better blood test for EPM. Just had a horse tested. Fortunately, he was negative. I don't have the link for the article about the new blood test. But I found it pretty easily Googling. Think there was an article in The Horse.
PM me if your vet doesn't know the new test. I can give you my vet's phone.

[dwblover]

UC Davis has a MUCH more accurate blood test now. I just had it done on my guy, who thankfully showed 0% exposure. They say it's just about as accurate as a spinal tap and MUCH less invasive. Just insist they do the IFAT and send it off to UC Davis.

[dressagevettech]

Like others have said it does show up in many different ways.
My mare was on/off lame in the hind end for a few months, and you could never pin point what leg it was. Then she got to the point she was having trouble picking up a canter, and off to the vet clinic she went.
On the neurological exam she had mild weakness in her hind end, mainly the right hind.
We sent in the blood test to UCDavis (the IFAT) and she came back 33% likely to have EPM. My vets were no convinced and we did the spinal..which also went to UCDavis.
That came back very positive.
So while it can be seen as invasive I do think in the cases that are iffy that it does help add more information to solve the puzzle.
And working there as a tech I saw many spinal taps done and never saw any complications that would make me hesitant to do a spinal. So long as you have a good vet who has done many of them, and it is done in a clinical setting, I think it is something that should be considered.

Thankfully with a course of the compounded EPM paste (4 months worth) my mare is back to work and doing great.

[Lone]

Thanks so much everyone. My vet said we had to send the blood to California for testing, so it must be going to UC Davis for their test, I'll make sure and double check with her on Monday when she comes out to draw the blood. I'm glad to hear the blood test is more accurate than it used to be!

And yes, this has been incredibly frustrating- at this point I'm really just anxious for an actual diagnosis (even if it's bad) at least then we could start making plans and figuring things out.

Thanks again for the information and knowledge! You COTH people are incredible : )

[GatoGordo]

About the spinal taps -- they do NOT need to be "under" for a lumbosacral tap, just sedated.

[2horseowner]

Sorry, when I said "under", I meant sedated. I've always used that term for sedation. Sorry for the confusion!

[goodhors]

Not sure how big your budget is, but a spinal will cost you a LOT. The spinal also has a HUGE chance of being contaminated with blood during the process. If contaminated, the fluid is useless and you must get another sample. Last I heard locally, a sample was over $600, probably times two.

When we suspected EPM, we did the common blood test and it did prove postitive. Our older Vet said almost ALL pastured horses in MI WILL test posititve. MSU could not get a set of horses for a study of EPM because everything they could use was contaminated already!!

Vet advised just going ahead without a spinal test, since the Marquis was going to cost about the same amount. Giving horse the meds would probably FIX him, not put us lots deeper in debt. Especially if horse needed a second course of the Marquis. Vet said horse should show improvement inside a week, if he was going to get better. Vet was correct, horse was definately improved at the end of 7 days, and continued to improve over the 30 days.

This horse was caught VERY EARLY, problem visible in crabby attitude, some mild incoordination that could have been missed if we didn't know him so well. He was MUCH happier within that first 7 days, mostly back to himself even before ending the Marquis. Not crabby anymore, part of the herd again instead of isolating himself like before.

With the EPM in horse system, the stuff can get loose from spinal area into horse system under stress situations. This horse was stressed a lot with heavy showing, worrying because he was being hauled alone. He was used to hauling as part of a Driving Pair. He recovered 100%, got his coordination back, with no recurrences of problems in the 4 years since.

I would just go with treatment, skip the spinal to save the money. Best of luck with your horse.

[Lone]

We pulled blood today, it's getting shipped down to UC Davis for the test they do there.

We also tested her levels of muscle enzymes in her blood (looking for some kind of muscle disease) we got the results back from that this evening and it was negative. Hoping to hear back about the EPM by Monday or Tuesday next week.

Do most horses have a fairly positive outcome and recovery? I only know one horse who had it and he passed away.

How did your horse do on the treatment Lulu?

[smay]

When my horse came down with EPM this past summer, I heard lots of stories about horses recovering after varying lengths of treatment with Marquis - one month, two months, six months... I was prepared to treat him for however long it took, but unfortunately, the onset of his symptoms was very fast - within days - and although he started on the Marquis even before his IFAT test was back (positive), he did not recover. We had to put him down when he lost bladder function and became so uncoordinated he was a danger to himself and his caretakers.

[goodhors]

Have to agree, with sudden onset EPM, severe coordination problems, the Marquis is probably not going to save him. Husband only had our horse blood tested for EPM because I insisted. Our horse was totally unlike the others he had seen with EPM. They had the sudden onset type and they lost all of them.

I stressed that our horse was caught very early for a reason. Just looking at him work, no one would point at EPM as his problem. Just the fact that he had a NUMBER of odd things at once, much of which we were blaming on aging and having been a hard using horse his whole life. Seeing and working with him daily, you catch the bitsy stuff faster. Husband was not using him daily, not seeing the attitude changes, small problems of not being as very coordinated as horse normally is, that DD and I saw in her riding sessions.

For whatever reason horse improved his attitude so swiftly, it was quite visibly better before two weeks into the Marquis. Horse had no work, no stress, pastured with his friends during his time on the Marquis, per the Vet. Kid missed showing him at the Fair, but was more happy to see him improving. Vet had already told us that doing one session should fix the problem if it could be fixed. If severely spread, the protozoa might need a second course, but he hadn't seen any better healing with more than two sessions. Horse would be better or not.

Offering this history as an option to OP. MANY folks do not have unlimited funds to test for everything. Doesn't make them "bad". You can have much money invested in just testing, then have nothing left to pay for treating the animal with! Maybe STILL not have a real answer from the tests!! Horse has already tested positive with the blood test for OP. Just is "off" as our horse was, nothing you can pin as a cause.

If spinal cord is badly damaged, nervous system damaged showing issues, there is not much going to help anyway. I would not keep a horse who was damaged badly going. Not a real quality of life for him. I have not heard or seen much success with the sudden onset EPM. Horse wobbling, falling, tripping, the day after he appeared fine, is sudden onset, and his prognosis is bad. You need to let them go.

OPs horse does not have such severe EPM symtoms, has tested positive for EPM in blood, so a course of Marquis COULD be the answer. I learned much here on COTH, which is why I insisted on the cheaper blood test as a method of ruling OUT EPM as a problem source. Blood test was positive, saved us a lot more self-diagnosing on an aging horse, cash as well. We fixed him up with the Marquis, he is still sound and going fine. Got a fistful of blues at the Fair and other shows over the summer. AGE was not a factor in his problems.

[MassageLady]

Working with a vet, and my trainer at the track, when we even think a horse has EPM, they go on immune boosters immediately! This helps the horse to fight off the protozoa themselves, instead of the Marquis (costing $$$$) killing them off and causing a whole nother set of problems with dead protozoa in the bloodstream! This has ALWAYS worked for us. You can find it cheap on herbalhealer.com
Just get the 4 herb tea concentrate, and add it to the feed.:D

[Woodsperson]

Like everyone said, the new blood test out of UC Davis is much improved. When my vet diagnosed Woodrow with EPM, we used the blood test in conjunction with a neurological coordination test. (We actually tried for a spinal, but the vet could not draw fluid. He called vet school at A&M and was told that sometimes it happens (rare). Just not able to draw enough fluid).

I would caution against using Marquis in lieu of testing. Woodrow started improving on Marquis, but midway through the second month he stopped getting better and actually got worse. We ended up having to go with the Navigator treatment. I was concerned about using Navigator, and we did have to discontinue it and restart a couple of times due to side effects, but it cured him (that and a fabulous barn owner that dosed him daily, took his temp twice a day, and watched him like a hawk).

[Lone]

I'm glad to hear about so many horses making a good recovery, I was really worried this would be a career ending sentence if the test came back positive.

I'm sure it can vary significantly, but how much does the treatment usually cost?