Interpreting your Lyme test, NOT that easy!
I have been writing to you about my involvement with Lyme disease and other tick borne illnesses for over six months. Through the letters one can see the vast involvement and damage these disorders can cause and can present in many different ways often mimicking other conditions. In my practice, I primarily see patients who have been undiagnosed for month or even years, often not receiving any treatment or not being treated appropriately.
Part of the frustration in the Lyme community is the fact that there is no one good test that is accurate. The test that we have now is up to 50-70% inaccurate in some instances. Intern, if you test negative for Lyme disease on regular blood work – it doesn’t mean you don’t have Lyme. In fact, recently the state of Maryland signed a bill into law that requires health care providers warn patients in writing that Lyme disease testing can be problematic and standard laboratory tests often result in false negative and false positive results.
So what do we do? Well, my suggestion is educating yourself which is the reason for this News Letter.
When Lyme test is ordered through a regular lab, it goes through a two tier approach: ELISA and Western Blot - WB (3 IgM Antibodies and 10 IgG Antibodies) screening test. When ELISA test comes back positive, only than a Western Blot test will be run which tests for specific antibodies for Lyme disease. If you tested for ELISA and 2 out of 3 IgM Antibodies came back positive on WB, you are positive for Lyme, or positive for ELISA AND 5 out of 10 IgG Antibodies positive on WB = you have Lyme.
The issue: a patient may falsely test negative for ELISA and so the bands will never be run/reported, or patients may test positive for a number of bands but not enough to meet the CDC/IDSA guidelines delineated above.
Another important point is that not all WB IgM and IgG bands are created equal. If you speak to Lyme Literate Doctors (LLMD) they will tell you that some bands are more or less specific for Lyme disease. Therefore, many LLMD look at quality of the bands not quantity in conjunction with assessing the clinical picture including physical findings.Bands that are considered to be Lyme specific according to the International Lyme And Associated Diseases Society = ILADS guidelines: 18, 23, 30, 31, 34, 39, 93.
Please note that some LLMDs also advocate the use of specialty laboratories to test for Lyme and associate diseases which many report is a more accurate way of looking for serologic evidence of exposure to tick borne illnesses.
Take away points:
Just because you tested negative for Lyme disease – does not mean you don’t have it!
See an LLMD (Lyme Literate Doctor) if you have symptoms that are not explained by other physicians and you suspect a vector borne illness.
Educate yourself on your illness and ask your physician direct questions about your specific concern.
Be well this Holiday Season!
Elena Frid MD
Pediatric and Adult Autoimmune Neurology Specialist