how effective is auricular acupuncture in treating this condition?
My personal choice would be to use more body acupuncture than auricular for this condition. That is a personal bias of mine, however, although I would imagine clinical studies that compared body and auricular for a condition such as this would favor body acupuncture or combination vs. auricular alone.
Within the Tam Healing system I use we would foacus on the huatuo points of T1, T2, and T3 for the bone marrow, thymus, and lung system respectively which alter the auto-immune component of this condition. The huatuo of T7 on the right side which is used to effect circulation of Blood in the abdominal region, the huatuo of T8 on the right side for the pancreas, and KD 22. Other points would be added according to your training and the persons unique set of signs and symptoms (SP 6, ST 36, CV 6, CV 13...).