TDRD6 and primary hypophysitis: In addition, autoantibodies against pituitary tudor domain containing protein 6 (TDRD6) has been demonstrated to be present in almost half of the patients with APECED but not in patients with T1D, systemic lupus erythematous, lymphocytic hypophysitis or other autoimmune diseases [30,31], but the TDRD6 autoantibody titers do not seem to correlate closely with hypopituitarism in APECED.