Autoimmunity is a known factor in the pathogenesis of islet cell destruction, but
little is known of its role in the pathogenesis of the neuronal complications of diabetes.
We carried out a cross-sectional study of 94 subjects with Type I diabetes mellitus
(DM) to examine the relationship between duration and presence of complement fixing
anti-adrenal medullary antibodies (CF-ADM). CF-ADM were present in 19% of subjects
(n = 62) with duration of DM ≤ 16 years and 3% of subjects (n = 32) with duration
of DM > 16 years. All subjects with CF-ADM+ and duration of DM 0-5 years (n = 7) were
islet cell antibody positive (ICA+). Among subjects with duration of DM 6-16 years
who were CF-ADM+, 4 of 5 subjects were ICA- and 1 of 5 subjects was ICA+. The only
CF-ADM+ subject with duration of DM > 16 years was ICA-. Absorption of ADM+ and ICA+
sera with upper phase glycolipid extract blocks ICA but not ADM binding to tissue.
This study suggests: 1) CF-ADM positivity is associated with ICA positivity in subjects
with duration of DM 0-5 years. CF-ADM positivity persists after 5 years duration of
DM when islet cell antibodies have disappeared. Therefore, the antigenic target of
the adrenal medulla and pancreatic islets may be different. 2) There is an increased
prevalence of CF-ADM in subjects with duration of DM 0-16 years (P < .05). We hypothesize
that the increased prevalence of CF-ADM in subjects with DM of 0-16 years duration
may precede the onset of autonomic dysfunction. Longitudinal studies are necessary
to further test this hypothesis.
Autoimmunity - Adrenal Medulla - Autonomic Nervous System
