Acute painful diabetic neuropathy: two patients with recent insulin-dependent diabetes mellitus.

Two young men developed an acute painful peripheral neuropathy a few weeks after being diagnosed to suffer from an insulin-dependent diabetes mellitus. In both cases, peripheral nerve biopsy exhibited a few features of acute axonal degeneration. Additionally, in the first case there was a lymphocytic infiltrate around an endoneurial capillary, and in the second case there were several mast cells in the endoneurium of every fascicle examined. A few months later, the acute pain had disappeared in both cases. Only a few cases of acute painful diabetic neuropathy have been reported so far. A vascular origin seems unlikely and metabolic disorders are probably due to a contemporary severe weight loss. An auto-immune mechanism is an alternative explanation.