Definitely pursue the Lyme/ coinfection connection. The CDC criteria were originally set up as a tracking criteria. As a diagnotic criteria - they miss many cases of Lyme. As mentioned, testing at Igenex is highly recommended. They have set up their own criteria - based on testing experience - that includes more Lyme specific bands.
Lyme is primarily a clinical diagnosis with testing playing a supporting role. The presence of even one of the Igenex Lyme-specific bands could be clinically significant if you have symptoms. The tests are indirect and measure antibody response rather than testing directly for the bacteria. There are many things that can suppress this - if your immune system has been under attack for some time, you may have limited ability to produce antibodies. There is even some evidence that some people have limited response due to genetic reasons.
Most LLMD's don't accept insurance. That is my case too. I'm four months into treatment now and I think the way to view this is - you can't afford not to. As my doc says, "Lyme is a smart bug that doesn't want to kill its host." It can sit there as a drain on your immune system. If you get stressed or sick with something else in the future, the Lyme can become more active.
The bacteria are spirochetes and can basically got where ever they want to in your body. Many different body systems can be affected. It tends to be a deep tissue thing and favoite targets are joints, spinal fluid and it can pass thru the blood-brain barrier. That's why this disease can have so many symptoms. Another common spirochete infection is syphilis. You wouldn't just ignore that and hope for the best, right? Or hope it just goes away?
At least Lyme/coinfections are treatable. Once it's dessiminated tho, it will likely be a slow process.
I don't want to "over-information" you here, but if you'd like I can post links to Int. Lyme and Assoc. Diseases Society (ILADS) and also to some up-to-date treatment guidelines.
We're used to thinking of tests as being definitive and looking at docs as authority figures. Lyme disease is one of those things where you need to be more informed and be your own advocate.
Please post with any questions you may have and we can try to help answer them.