Please consider that auto-immune diseases may be infectious in origin. Remember when George Bush Sr., Barbara Bush and their dog all were diagnosed with Graves' Disease?
A case might be made that there is no such thing as auto-immune disease. The body may be attacking a bacteria, fungus or virus that has not been identified.
Similarly, Lupus and Rheumatoid Arthritis may fall into diseases that are not actually auto-immune. David Brownstein, MD, has some thoughts on this: