Testing for lyme disease is a tricky thing. The available tests are not very reliable, but from my understanding the Western Blot test is the best we have. It tests your blood for two types of antibodies – IGM, which signifies a current infection, and IGG, which signifies an older infection. If your test is positive, you 100% have lyme disease. But if it’s negative, it’s possible you still have lyme and it just didn’t pick up enough of an antibody response. In other words, false negatives are common, leaving doctors to diagnose primarily based on symptoms (which, unfortunately, most aren’t educated about).
There are several markers of lyme to test for, and different labs test for different markers. Many believe that Igenex laboratory is the gold standard, testing for the broadest range of markers. This is where I had my blood test sent.
To make things even more complicated, there are different perspectives on what constitutes a “positive” test result. The center for disease control (CDC) set very strict standards, requiring that you test positive for 2 specific strands of IGM antibodies, or 5 specific stands for IGG antibodies. Igenex, however, has more accurate standards – including more markers in their results and weighting them differently. Testing positive for a protein found in the tail of the lyme bacteria, for example, weights your results more positive than just testing positive for a spiral-shaped bacteria (spirochete) which may or may not be Lyme. Makes sense to me.
The Western Blot comes back showing multiple markers for lyme disease, one on each row or your results. For each you will show – (negative), + (positive), or “IND”. If it’s positive, the number of plus signs (1-4) will indicate how strong your antibody response was on that marker. IND means that you had a response, but it wasn’t quite strong enough to be a complete positive. Most lyme-literate doctors will treat this as a weak positive.
My test results came back on June 4, 2015. It was the day before my 10 year anniversary of my multiple sclerosis diagnosis. I walked into my naturopath’s office curious to know whether someone got it wrong 10 years ago, and excited that this could be a path to wellness.
Thank goodness I’d done my research on interpreting the Western Blot test. She handed me my copy and we went through it together.
First we went through the IGM results for a current/recent infection. Both the CDC and Igenex require you to test positive in 2 of the starred markers. I tested positive in one of the required rows, and “IND” in another. She said I was negative. I knew that “IND” should be interpreted as a “weak positive” and recognized that I had a potentially positive IGM test result here in my hands, indicating a possible current infection.
Next, we went through the IGG results. Here the CDC and Igenex have different standards for a positive. Simplifying, Igenex says you are positive if 2 or more of the starred bands are positive. The CDC requires at least 5 of the following bands to be positive: 18, 23-25, 28, 30, 39, 41, 45, 58, 83-93. I had 2 very clear positives on the double starred bands, and one “IND”; I was very clearly positive by igenex standards. By the CDC, I had 4 of the required bands clearly positive, meaning I was pretty close to being positive even by the CDC’s strict standards. Either way, any Lyme-literate doctor would look at these results and my 3-page list of classic symptoms and know right away I’ve got late stage Lyme.
Notice my uneducated natruopath kindly circled “negative” next to the CDC result for emphasis 🙂 “You very clearly don’t have Lyme disease,” She said. “If you were even borderline, I’d suggest 30 days of antibiotics to clear it right up, but you’re not.” Lymies will recognize the absurdity of these statements right away! A) this is a positive test result I’m holding, if you have an educated eye, and B) we all know late stage Lyme disease cannot even remotely be cured by 30 days of antibiotics. I turned down her suggestions that I triple my thyroid meds and begin hormone therapy, and left her office with a clear path in mind.
It was time to see a lyme-literate physician to discuss these results.