I have a friend that was diagnosed with Rheumatoid Arthritis and was taking those nasty drugs for 2 years. They weren't helping and she decided that she didn't have Rheumatoid Arthritis and had a lyme disease test done. Apparently there are 7 or 8 different lyme diseases you can have.
Anyway after all the testing, she found out that she doesn't have Rheumatoid Arthritis, she has Rocky Mountain Spotted Fever. I guess the symptoms for the arthritis and lyme disease are very similar to the Fever.
Most of the time the doctors will only give you one test instead of the multiple ones that are out there for lyme disease.