Blisters, ulceration and autonomic neuropathy in carpal tunnel syndrome.

We describe three patients with trophic ulceration and blistering of the fingertips associated with carpal tunnel syndrome. One of the patients also had non-insulin-dependent diabetes mellitus. Autonomic neuropathy distal to the carpal tunnel was probably present in all subjects at the time of presentation; in the patient with recent symptoms the skin was warm, and sweating was virtually absent, whilst the other two patients described cold skin, consistent with prolonged autonomic neuropathy.