Rhonda,
I don’t know about a Dr. that just treats autoimmune things since they can affect so many systems in the body. I.e. my mom has uveitis, an eye issue that’s autoimmune, that I am sure another doctor not trained in that field wouldn’t want to touch. You might be able to find a hospital based practice that supports and endocrinologist and a rheumatologist that know each other and would advocate for you with each other. I can’t remember where you live. A teaching hospital might be a good bet.
Have you looked at any of the NIH web sites, NCBI, medline for statistics? You might google that question and click on scholar at the top to get papers that might help you out.
ewmb