Lyme vaccine causing a positive lyme test?

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Little Angel
Barked: Thu Dec 31, '09 9:46pm PST 
I was just wondering about this because I mentioned it to one of the vet techs that was helping out Angel in our last appt (after we switched vets.)

My first dog, Rocket, I got a Lyme vaccine because it is very prevalent in the area. Not to mention he had a whole host of other problems including worms and being very underweight, I didn't want to add lymes to the list.

At the second checkup (for his second lyme booster) he was tested for heartworms so we could start his hw preventative. Well, the vet broke the news to us that he tested positive for lymes disease and needed to be treated to be on the safe side. Wanting to do the best for our dog, we agreed, paid the 50ish bucks for the meds.

It was a TON of medicine, 3 pills a day for...60 days? or 30? But he had diarrhea the entire time...trust me I never ever would want him on it if he didn't need it to be...and I never want to put meds in my pups that they don't need.

So, I mentioned it to the tech and she gave me this funny look. Then she said "you know, a lyme disease vaccine can make a test show up positive..."

Is this true? If so I would be absolutely LIVID. Why wouldn't he test BEFORE just in case? Did he just try to squeak money out of me?

Code name:- Farmcollie
Barked: Fri Jan 1, '10 6:33am PST 
If you are doing the Idexx SNAP® 4Dx® Test that checks for heartworm disease, ehrlichiosis, Lyme disease and anaplasmosis...

http://www.idexx.com/view/xhtml/en_us/smallanimal /inhouse/snap/4dx.jsf?conversationId=85098

...the test is designed to only indicate if a dog has been infected, not if it has been vaccinated.

However, blood titer tests that are often done after initial diagnosis of infection often will mistake a vaccination for actual infection.

So, if you did the Snap 4 test, your dog has been exposed to actual Lyme disease, and probably does merit treatment.

Here is a good website that covers tick disease issues. I highly recommend it:

Leah, CGC

All the Beauty- with none of the- Brains
Barked: Fri Jan 1, '10 7:54am PST 
Chandler has pretty much covered what I was going to say regarding the 4DX test. By theory you can come up positive because it tests for antibodies but the Idexx has run numerous testing on their new 4DX and has not seen this occur. I have not seen it with the new 4DX.

That being said . If this is the first time he has tested + I would treat with the doxy. If he has tested + in the past and then tested + now, you should understand that the 4DX is a antibody test therefore it will show up + whenever there are antibodies in the pets system. We are unclear about howlong in takes for antibodies to exit the system once an infection is present (ie if you test + and give the full course of antibiotics and immedietly test again chances are you will still show + but not have a active infection). Because of this many vets will give antibiotics for every + shown on a 4DX and some vets only treat active infections (ie once showing symptoms of Lyme disease like limping, lethargy etc)

Where this gets sticky is what constitutes a symptom? Many dogs don't show regular symptoms and often are walking around infected with lyme disease and the owners are not really aware. Untreated lyme disease can result in lyme nephritis (a very lethal kidney infection caused by lyme). Doxycycline is generally a pretty benign treatment so many vets feel more comfortable treating all + 4DX animals to avoid a worse outcome if left untreated.

If you are truly concerned about whether or not this is an active infection the only way to definitivley diagnose lyme disease is with a Lyme C6 titer from Idexx Lyme C6 The results take about a week to come back. Idexx ideally would have every 4DX + dog followed up with a C6 check.
Taken directly from this website "C6 technology lets you monitor response to treatment. A unique property of the C6 antibody is that levels decline sharply after treatment, before the body can produce memory (B) cells. The lack of memory (B) cells means the body does not maintain a titer after the spirochetes are killed. Other tests, such as the Lyme titer (IFA) and Western blot tests, measure antibodies that can persist at high levels long after treatment, making it difficult to determine whether the spirochetes are still present, even after treatment."


Little Angel
Barked: Sat Jan 2, '10 9:29am PST 
He didn't have any symptoms when we got him, and actually I have no idea what test he gave him. All I know is we got him his vaccine, then the next time we came in he said he had "lyme disease antibodies" and didn't know whether or not it was a past or present infection, but thought it best to treat it like a current infection, which we agreed. (I know about lyme, its not fun and can cause a ton of problems.) Theres no doubt in my mind I'd rather pay $1000 bucks and take care of it then let him possibly get it.

No matter what, even if someone told me it could have created a false positive, I would have treated him for lyme. I just think that if he KNEW we were coming in to set up for his heartworm test next appt, he would have WAITED on the lyme vaccine or told us to get tested now because of that.

I was just wondering if I was swindled or not, as the vet tech had suggested. (Not to mention he was already on other medication due to other problems and I detest over medicating dogs, we adopted a very sick pup, but he's all better now! cheer )

I guess it was just bugging me because this was the same vet that refused to prescribe anything other what HE sold at his clinic. When we requested different medication because of health concerns for both the pups he basically treated me like a neanderthal when I said I didn't want to put Angel on ivermectin, and his receptionist was VERY rude and said we would be irresponsible to try any other flea treatment on Rocket after he had his seizure. (We questioned whether or not it was because of it. Even though we understand it may have just been a coincidence...we do not want to risk it if we don't have to.)

But, we have a new vet now that is really great and understanding. (And took one look at Angel and said any vet that wanted to prescribe him ivermectin is either insane or stupid.) I pay about double to go to him, but its worth it, especially since he seems to be familiar with the genetic issues Angel has.

Edited by author Sat Jan 2, '10 9:32am PST