Anti-Adrenal Medullary Antibodies in IDDM Subjects and Subjects at High Risk of Developing IDDM

Previous reports have noted the presence of antiadrenomedullary antibodies in subjects with insulindependent diabetes mellitus (IDDM). We initiated a study to evaluate the presence of complement-fixing anti-adrenomedullary antibodies (CF-ADM) in the following subjects: group 1 (age 4–60 yr), anti-islet cell antibody-positive (ICA⁺) subjects at high risk of developing diabetes, in which 9 (32%) of 28 were positive for CF-ADM; group 2 (age 6–41 yr), anti-ICA negative (ICA⁻) subjects at high risk of developing diabetes, in which 0 (0%) of 15 were positive for CFADM; group 3 (age 1–58 yr), ICA⁺ diabetic subjects, in which 7 (30%) of 23 were positive for CF-ADM; group 4 (age 5–68 yr), ICA⁻ diabetic subjects, in which 1 (4%) of 24 was positive for CF-ADM; group 5 (age 20–56 yr), volunteer blood bank donor controls, in which 2 (6%) of 32 were positive for CF-ADM; and group 6, known healthy controls, in which 0 (0%) of 14 were positive for CF-ADM. CF-ADM were increased in group 1 compared with group 2 (P < .02) and both control groups (P < .02). CF-ADM were increased in group 3 compared with group 4 (P < .03) and both control groups (P < .03 vs. group 5, P < .05 vs. group 6). Presence of CF-ADM was associated with presence of ICA in group 1 (P < .02) and group 3 (P < .03). In view of these results, adrenomedullary autoimmunity is emerging as a new member of the human organ-specific autoimmune disorders. It occurs before the development of clinically overt diabetes and is associated with the presence of ICAs. The functional significance of adrenomedullary autoimmunity needs to be evaluated.