Mononeuritis multiplex in diabetes mellitus: evidence for underlying immune pathogenesis.

Four patients with type 2 diabetes mellitus developed mononeuritis multiplex subacutely. Sural nerve biopsies showed multifocal axonal loss in all patients, with epineurial perivascular inflammation affecting small calibre vessels in three. Three patients improved with immunotherapy. These observations suggest that mononeuritis multiplex in diabetes may be caused by an immune mediated vasculopathy and that it is pathogenetically akin to the more common and better recognised diabetic amyotrophy.