Autoimmune markers and neurological complications in non-insulin-dependentdiabetes mellitus

To verify whether autoimmune markers related to nervous system structures a nd other autoimmunity indexes present in diabetes mellitus are associated w ith subclinical neuropathy, we examined 48 non-insulin-dependent diabetic p atients with and without neuroelectrophysiological alterations. Nerve condu ction velocity at the external sciatic-popliteal nerve, at the sural nerve, at the median and ulnar nerves level has been evaluated. Autoimmunity was investigated by evaluating glutamic acid decarboxylase (GAD-Ab), insulin (I AA), GM3, GD3 and GT1b gangliosides, pancreatic islet cell (ICA) and anti-n ervous-tissue autoantibody presence. Nerve conduction velocities were decre ased in 72.9% of diabetic patients. Anti-insulin antibodies were detected i n seven non-insulin treated diabetic patients and in higher amount in subje cts with (17.1%) than in those without (7.7%) asymptomatic neuropathy. Anti -GM3 antibodies were detected in four diabetic patients all of whom present ed neurological complication. A significant correlation has been found betw een neurological damage and presence of anti-insulin antibodies (p < 0.05). In the case of GM3 autoantibody, a similar result was obtained, but the da ta failed to reach statistical significance. Our data demonstrate that auto immunity might play a role in the development of peripheral neuropathy, (C) American Society for Histocompatibility and Immunogenetics, 1999. Publishe d by Elsevier Science Inc.