I got results back for my horse. I tested him for lymes and epm. I don’t have lymes back yet tho. He doesn’t show the major sign of epm like weak hind but he can be overly sensitive to sounds and touch and then he can stand splayed out on front end at times which I read could be a signs? so I just tested. I don’t have a results to read right now being vet just told me the results. He said it came back 33% chance of epm. I’m not sure what that means and again I have not seen report to look at and I’d have to look for sure where they sent it. The vet said he thinks that would qualify him as negative? I’m curious for those who did get epm test, did u get like a percentage? It was sent with serum.
The EPM tests my vets have sent are reported as a titer which is a ratio like 1 to 40 or 1 to 80. My old guy had a titer of 1:320 at his initial diagnosis with classic hind end symptoms and responded to Marquis. Unfortunately, he relapsed a few months ago and his titer was greater than 1:640. That’s the serum test. I understood that to be quite high. I think the 33% your vet mentioned is the estimated probability of EPM with a low serum titer result (1:40). Good luck getting a diagnosis.
I have been reading and it’s hard to get a true epm diagnosis unless really high. May be wrong tho. I also read many horses will test but not have true symptoms! So idk!
Where in the country is your horse located?
EPM is difficult to diagnose, and a positive test doesn’t always tell you much. You need to find a vet who is experienced - very long experience of lots of EPM patients - with EPM where you live.
I’ve been told authoritatively that in the southeastern U.S., including east Texas, probably most horses would test at least mild positive for EPM, because the source is so widespread. That doesn’t mean they have an active case.
For that reason, many vets don’t encourage owners in the SE to get an EPM test. It’s expensive and the results might be more confusing than helpful. Some vets feel that if the symptoms are all in a certain direction, it is worthwhile to go ahead with EPM treatment, without the test. The horse either shows improvement, or they don’t, and that can help direct future action.
If you do test, reading and understanding test results does need someone with local experience who knows what the results most likely mean.
All that said, it is important to try to understand and address EPM sooner rather than later, due to potentially long-term negatives. The sooner intervention happens, the better the chances are for full recovery. The more intense the case, the harder it may be to get rid of it. And of course EPM can slowly take a horse’s life.
There are other parts of the country where EPM is not common, and a test can definitely help.
At least EPM isn’t contagious. Given how frequently it crops up on a test, that would be a nightmare.
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I have read that to. I live in Midwest(Iowa)
I’ve treated several borderline cases and was always happy I did. I think there are a lot of milder cases that are missed because they don’t cause any neurological deficits.
I have never seen a percentage on the results. It’s always a ratio.
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Since you were concerned enough about your horse to test, I think OverandOnward’s advice is good. Wait for the Lyme test results and then discuss with your vet.
There are people here who can give you an educated opinion. If your vet is not familiar with these issues you may choose to call the nearest Veterinary teaching hospital in your area to help you interpret the test results.
I believe the current Veterinary approach is that, depending on symptoms, there is less harm in treating the horse compared to the possibility of EPM and/or Lyme untreated. Good luck and let us know how the Lyme test comes back.
My vet when he came to take test didn’t think I should test for epm but just for lymes bc he said he didn’t show classic sign which was was weakness or something. Mind we live in a very very remote area in Iowa most vets are cattle swine here not horses. When I looked online signs of epm stiffness, incoordination, weakness, lameness, then signs of lyme are muscle spasm/pain, lameness, shifting leg lameness, weight loss, heed some ppl has horses who were just reactive easily etc. I have never pulled a tick off my horse or seen one but doesn’t mean I guess he never had one or does that I found. I mainly tested him for both bc for me is still cheaper then testing for pssm2 if that’s a possibility.
The last time I ran an EPM test was in 2015. It was a serum test also but there was no percentage. The results were reported as a ratio ranging between <1:250 (negative) and >1:4,000 (high).
This might be good reading for you: https://images.saymedia-content.com/.image/cs_srgb/MTQ4NTg1OTA5NzI4NTg0OTg1/eqm-1705-aaep-resort-symposium-report-final.pdf. One excerpt: " A positive serum test indicates exposure to the organism but does not confirm CNS infection, regardless of the magnitude of the titer. Low positive serum titers are commonly seen in horses that do have EPM, while high positive serum titers are commonly seen in horses that do not have EPM.
I got lyme test back and it’s negative and epm says titer of 40
Is that a SAG1 ELISA titer? 1:40?
Ok. The IFA Sarcofluor is not a test I’ve had run, but ours from the east coast go to Cornell not UC Davis. According to the UC Davis website, <40 low probability, 40-80 is the maybe area, and >80 is high probability. Their diagnostic flow chart seems to suggest that you do a spinal tap for a definitive diagnosis if you are between 40 and 80. I’m sure there are some other west coasters here who can chime in with their own experiences with results on this scale.
Realistically, I don’t know anyone who spinal taps anymore for EPM. You just treat and see if it produces improvement. Marquis is a relatively safe drug.
Like I stated I do not live in a horse populated area where I have all these equine vets who know all about it! But they sent it off first to cornel where the Lyme test was done but bc of covid or something they weren’t running epm test idk and sent it back and then the vet sent it to another place.
I’m not going to do anymore testing. Is the marcas drug or whatever u mentioned, cheap or is it pretty expensive? Do u have to go thru a vet?
A 1:40 ratio is considered by most vets here (at least) to be negative, and most would not treat. It sounds like this horse wasn’t overtly neuro on exam? If not, there would be other things to look at first. Marquis is not cheap and is a prescription, so your vet would need to be on board.
I would wait on the Lyme titer to do anything.
No Nero issue when vet did them. His Lyme came back negative
Is the spookiness (sensitivity to sound and touch) new? What do you mean when you say the horse stands “splayed out” in front? Is that stance new? How old is the horse and how long have you owned him/her?
You describe your vet as unfamiliar with horses and EPM or Lyme lab results. What sort of neurological exam did the vet perform when they examined your horse?
He just sometimes stands like toed out. Wider stance on front end. Idk how to explain it! I had horse since 8 months he will be 4 in April. My vet is only vet around who even does horses so I just mean there not like familiar with more in-depth horse stuff. They didn’t run test they sent them off obviously but he wast familiar with how to read the results etc but just said he think my horse is negative bc he doesn’t show many strong signs that he is familiar with like the drunk walking and neurological things. This sings he is showing could easily be something else. He did the pulling tail and such and nothing. No weakness. No Weight loss. But the sound thing and the shifting of back legs has been going on for awhile like a year or so. I just thought he was more sensitive to out of blue noises then normal. He can have muscle stiffness to which is was told by some there horse was Lyme positive and was sensitive to noise and muscle issue etc but he is negative. So I decided to just test for epm lyme. Being my other option I was going to do was test for pssm2 thru equiseq. He is pssm1 negative. But I decided to test for epm lyme first in case he did have one of them that needed to be treated I would know if I just tested for pssm2 bc I wouldn’t of tested for epm lyme and he could go untreated sorta thing. He is currently on a pssm2 diet
