My son is 11 with t1d. He also has dermographic urticaria, or skin writing, which is another autoimmune disorder, & he is allergic to antibiotics (or presents as such with severe swelling & hives) He has reacted badly to every single family of them. We are currently going to Duke for another diagnosis. My Mother had RA so I am very familiar with it. How old is your son? RA is so rare in children. Bless his heart.