Wednesday, February 26, 2014

An Understanding of Laboratory Testing

At Lyme support group meetings we are often asked many questions about the testing methods for Lyme disease and co-infections. Which ones are best, most accurate, least expensive, what they actually test for, how sensitive they are, what the differences between sensitivity and specificity are, and more. So, some interesting and deep reading about Lyme disease testing can be found here.

Also, here is a quote from Advanced Laboratory Services about their Borrelia (Lyme) culture test:

"The culture that we perform grows the genus Borrelia so the particular species does not really matter although it has been reported that the most common form of Borrelia found in North America is Bergorferi.

There are other species that are commonly found in Europe that we would pick up in our culture. We do not report strains of the Borrellia.

We cannot guarantee that the specimen that you submit to us will contain the spirochetes even if you are presently infected."
The last paragraph basically says there can be false negatives from their test. This is because the bugs can live in places other than the blood stream, or because the sample taken at the moment you happen to be in the clinic doesn't happen to contain a spirochete, or other form of Bb.

However, the reverse is apparently not true: This makes sense because if, without intervention, a sample of your blood grows a spirochete that the technicians can stain and observe under a microscope slide and it's moving around, that means you have Bb in your blood. Period. Assuming there is no contamination of the lab sample, the sample was properly managed to allow the bacteria to grow in the lab, and the procedure for observing the bacteria is properly done, there should be no doubt that the lab tech saw what s/he saw. At least that is my understanding of it. I recently had a positive result from Advanced Laboratories Services, and looked into this in order to better understand the findings.

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