Anyone have any info on false negatives on tick borne disease tests?
Very rare or not?
What if the tests were a month apart, both negative, but the dog has all of the signs of a tick borne disease and is responding to Doxy treatment?
Just wondering...

did you just do the snap test? I would have them send it out to the lab? It's very frustrating my girls all had a recent snap test & all are positve with no signs.... so i'm not treating.
Good luck!

The tests were sent out to a Lab.
I have heard of another dog that also has tick disease systoms with negative test results.
Not sure just what to do?????

Positive results with no signs and negative results with all the signs???????????
What to do????????

Could you let us know exactly what tests were run? There are several different tests for several different tickborne diseases.

For example, test could be negative for lyme but the dog could have Ehrlichia, or RMSF, etc..

Thanks!
Valerie

If the dog is showing symtoms of one or more of the tick bourne diseases I would consider doing further testing. The snap tests simply show whether the dog has had exposure to the disease. Further testing will show if the dog has one or more of the diseases active in their system.....there are so many strains of Ehrlichia that I would test for all of them.

There are lots of tick diseases out there - far more than are tested for on a routine basis. One of my girls came up sick and acted like she had a tick disease. My vet wisely treated her as if she had a tick disease and she improved, but not 100%. After a few months of my dog just not being herself I decided to do further testing for more obscure tick diseases and sure enough, she came up positive for bartonella. Bartonella requires Zithromax to clear it, so that is why she improved on the Doxy but didn't improve 100%.

BTW, the bartonella testing is expensive and also takes several weeks to get the results back. The bottom line for me is that if one of my dogs acts like they have a tick disease then I am going to treat for a tick disease. If they don't improve on Doxy then I'm going to the Zithromax. Better safe than sorry.

The tests that were done were for Lyme, Erlichia (sp?),
Rocky Mt Spotted Fever and one other that I cannot remember.
I'll check into the more obscure ones and get tests done on those too.
Thanks for the info.
If anyone has had a dog with a tick borne disease, please share your expierence as I know there are many people who worry about this and want to know more.
Thanks!

After dealing with an undiagnosed infection and several vets refusing to treat my old girl for Lymes because she had negative blood work for tick borne illness I started doing lots of research on Lymes. When I first took my girl in that was one of my FIRST questions to the vet...Could this be Lymes? The answer was no Lymes is rare in Michigan. Long story short she now has chonic lymes and this is a day to day fight for her.

Intersting facts about why you often get false negative on Lymes tests. Info taken from this site:
http://www.lymeout.org/seronegative.html

Nine Reasons for False Negative Lyme Disease Blood Tests


The Lyme Disease Foundation (LDF), in their brochure entitled "LDF Frequently Asked Questions About Lyme Disease" lists the following nine reasons for false negative Lyme disease test results:

(NOTE: The standard tests for Lyme Disease do not look for the bacteria, but rather the immune system's response to the bacteria. The ELISA and Western Blot both test for antibodies which is what the immune system produces when infection is present. Because the tests look for this indirect measure of infection, false negatives are not uncommon.)

A. Antibodies against Bb are present, but the laboratory is unable to detect them. [Borrelia burgdorferi (Bb) is the Lyme disease bacteria.]

B. Antibodies against Bb may not be present in detectable levels in patients with Lyme disease. Reasons are listed below.

1. The patient is currently on, or has recently taken, antibiotics. The antibacterial effect of antibiotics can reduce the body's production of antibodies.

2. The patient is currently on or has previously taken anti-inflammatory steroidal drugs (such as those taken to treat rheumatoid arthritis) or certain anticancer drugs. These can suppress a person's immune system, thus reducing or preventing an antibody response.

3. The patient's antibodies may be bound with the bacteria with not enough free antibodies available for testing. [I think this reason is very important and prevalent. For this reason, some of the worst cases of Lyme disease test negative - too much bacteria for the immune system to handle.]

4. The patient could be immunosuppressed for a number of other reasons and the immune system is not reacting to the bacterium.

5. The bacterium has changed its makeup (antigenic shift) limiting recognition by the patient's immune system.

6. The patient's immune response has not been stimulated to produce antibodies, i.e., the blood test is taken too soon after the tick-bite (2-6 weeks). Please do not interpret this statement as implying that you should wait for a positive test to begin treatment.

7. The laboratory has raised its cutoff so high that a patient's previously positive test is now borderline or negative.

8. The patient is reacting to the Lyme bacterium, but is not producing the "right" bands to be considered positive.


Lyme Disease Foundation
1 Financial Plaza
Hartford, CT 06103
(860)525-2000
fax (860)525-TICK
Lyme Disease National Hotline (800)886-LYME
email: mailto:lymefnd@aol.com

For more on false negative/positive Lyme disease test results see:

With the negative tick borne disease test results you may also want to consider Immune Mediated Thrombocytopenia (ITP). Its symptoms look like Ehrlichia. The only way to positively diagnose ITP is via bone marrow aspiration so it is most often diagnosed based upon symptoms, blood work & response to treatment. Low doses of pred and routine platelet checking is necessary in order to boot it out of the system.

I had a dog with ITP 3 years ago and we just had our 3rd in a row normal CBC (done semi annually as a precautionary measure now). As much as I hate the drug we did have to do small doses of pred to get her platelet count back up. She was never symptomatic and we caught it by accident when she was going under anesthesia and we did a pre-op CBC. Her platelets were very, very, low at that point and if it had progressed much further she could have bled out. It took a while (over a year) with conservative treatment before her platelets were consistently normal.

Good luck!

Aloha,
Kim