which type of lyme test did you test positive for and which one negative?
Did your neurologist describe the foci as white matter lesions? Girlie is right, white matter lesions in the brain and spinal cord can show up in lyme as well. I've spoken to a few docs and neurologists about
how "classic ms" and lyme white matter lesions tend to appear on MRI. And there are apparently some recognizable differences. It might be worth inquiring with your neurologist. It may not go anywhere, but it's worth getting him or her thinking about
Do you recall how many lesions or foci you had? And what size they were?
I do have an acquaintance who was diagnosed with ms and lupus at the same time, and then later discovered she had lyme. She was treated and is doing very well now. Not saying this is what you have, but a positive lyme test is an interesting piece to your puzzle.
I'm with Snoopy on his take of "pre-diagnosis". I have a friend who was told something similar a decade ago because she had a white matter lesion. There's been no change and the neurologists no longer wish to follow her.