I was just curious how many of you had a positve PCR--the clinic I go to in Huntersville told me that not a lot of patients have a +PCR.

any additional information or links to more information on this would be appreciated

While a positive PCR is accurate for Lyme, a negative one is not proof that Lyme is not present. The reason: it depends on the blood sample. Basically, you would have to test ALL the blood of someone to exclude DNA evidence of borrela.

You can do this with, say, a tick. The whole body is ground up and examined. But with a person, you get one vial of blood. Borrelia may not be in that sample. It's not like measuring oxygen or glucose levels or DNA blood type in which the entire blood reflects what is in the small sample. Finding borrelia via PCR is like finding the needle in the haystack, or a particular fish swimming in the ocean. Great if you happen to catch it where it is.

A similar case to make your point: PCR testing of Sperm. If you get a sample in the right place and get a positive PCR, you know you have your man. No question it's accurate. But if you swab, say, under the armpit and get no sperm evidence, what does that tell you?

Other reasons for lack of positive PCR--it's migrated mostly to the soft tissue, such as the brain or the heart. So it's no longer primarily in the blood. Or it is in synovial fluid in the joints, or in the spinal fluid. Or it is in cystic forms and not detectable by PCR or other blood tests.

I was involved in a clinical trial still in progress in which my blood was taken in five vials --so five samples taken within the same five minutes. The samples were sent to five labs for Western Blots. Two of them tested also with PCR. One lab had a positive PCR, the other a negative. And the Western Blots were all over the place with few consistencies. So much for testing! Fortunately, I already had a positive Western Blot from earlier, which was why I was able to take part in the trial.

Tell that clinic to go back to PCR 101 and to repeat this mantra: "Borrelia is not going to be found in evey milliliter of blood I happen to take."

--Annie

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Just to clarify, this clinic is not excluding a Lyme dx on the basis of a neg PCR. They are just doing research on a certain set of Lyme patients, the ones from the clinic who DO have a positive PCR. They diagnose lots of people with Lyme with both positive and negative testing using a variety of tests. A clinical diagnosis is given when appropriate.

I just didn't want you to have the wrong impression about this clinic. They do lots of different research studies. I, personally, don't know what data they are collecting on the one griswold girl is speaking of. But they are not excluding the diagnosis in any patients based on this.

This clinic seems to get bashed on this board sometimes, so I am just making sure others don't misinterpret this post.

Tested once (Igenex) serum and urine. Serum pos; urine neg. That was after 1.5 years of treatment.