Scott,
There is a group that feels all autistic kids have Lyme. The problem is you can run any Lyme test if it looks at enough markers and most everyone will show some positives. With that said I have seen some kids with definite criteria for Lyme and even had one child from San Diego with a PCR to Lyme.
The lab I have used is IgeneX – http://www.igenex.com. They are out of California.
I would normally do this as testing to be done later if clinical improvement is not being seen with other foundational intervention or if initially clinical history suggests exposure or child comes from a highly endemic area for Lyme.
Dr. Woeller