The following is an excerpt written by Dr. B.Robert Mozayeni included in our book Lyme Savvy: Treatment Insights for Lyme Patients and Practitioners.
In2008, when I looked at Borrelia Western blots I gave it sort of a 3 or 4 out of 10 in terms of how confident I would be in the result if I saw a positive. There are some Western blots so glaringly positive that no one would argue them.
That is part of the problem with the test. The result produced is along a spectrum of potential levels of confidence with great variability of clinical context. You can have a couple of weak bands and to a really sick patient with no other answers – those results can justify their treatment.
To a healthy patient, the same results would be interpreted as negative or normal. Context is always important, not only for interpretation of test results, but for choice and timing of treatment.
Great — but what if you get the wrong treatment because you have Bartonella causing weak positive bands on the Borrelia Western blot? Then you are going to have only a temporary improvement and a relapse.
Then Lyme doctors will start telling you “we can temporarily get you better but we cannot fix you.” Usually, as much as they may try, they don’t actually know the cause; or they do know and may not have the right treatment.
If you see only IgM-positive bands on the Lyme Western blot, then you definitely need to test for co-infections, especially Bartonella.
The Borrelia Western blot scores a 3 or 4 out of 10 in terms of my general confidence level because it is an indirect test, looking at antibody responses to a germ. There is nothing better than actually directly detecting a germ such as by detecting its DNA signature or at least its unique proteins encoded by the DNA. Then you can be sure you have that microbe. Unfortunately, a sensitive and specific test like this has not been available for Borrelia. Lately, some companies have developed enrichment culture methods. This is encouraging but fraught with pitfalls for potential contamination.
We need more experience with it to know how confident we can be. It depends on the actual laboratory technique they use to detect it, how they confirm that what they found is really Borrelia, and precautions taken to prevent contamination. They need to do full genetic sequencing. But if Borrelia burgdorferi has such a huge genome, while challenging, it will become much easier very soon to sequence the genome of every isolate of Borrelia found in culture.
As of Fall of 2011 we have a commercially available Bartonella test. We also now have a commercially available Babesia FISH test considered to be sensitive for Babesia for DNA detection. We now have better tests (in my opinion) for Bartonella and Protozoa than we actually have for Borrelia.
We have gone from a dearth of tests for Bartonella and Protozoa to having better labs than those available for Borrelia. Recently, better Borrelia tests, such as the Nanotrap® Lyme Antigen (LA) Test, have arrived.
If you are tracking antibody changes on a Western blot, it can be helpful to use a test that gives you a measure of the intensity for each band. A more sensitive measure may produce false positives but it can help follow the changes over time. The IGeneX sensitive Western blot has been helpful this way.
There are other Western blot providers which provide you with the other bands if they are positive. They will tell you if you have bands 31 and 34 even though they are not the ‘approved’ bands because 31 and 34 are specific to Borrelia. It is good to know if these antibodies are present.
There are definitely some caveats, but again my confidence level in the Borrelia Western Blot, on a scale of 10, is 3-4, or strongly positive, with all of the bands, a 9. Depending on the result my confidence level in the test would vary.
This is not a reliable test characteristic because you are always trying to recalibrate the result in your head and explain it to the patient and incorporate that probabilistic assessment in your patient care.
In other words, it is a method that yields ambiguous results that would support any clinical decision unless strongly positive or strongly negative.