A lot of your symptoms ring a bell with me and I have autoimmune issues....I can't hold a pen to write for more than a few sentences either....nor open bottles....I am having surgery to 'fix' the arthritis in my thumb, which has pushed my thumb over and caused severe weakness. I am very nervous about this, hearing about issues like you have. Anyway, I DO have severe hand issues, have PN and also an autoimmune disease too.