Erythromelia, or Mitchell's syndrome – new names for unexplained signs of inflammation in distal symmetrical neuropathy in diabetes

Abstract

Two cases are described in which distal symmetrical sensorimotor neuropathy complicating diabetes was associated with episodes of subacute vasodilation of one or other lower limb, and which were otherwise unexplained. The vasodilation was associated with swelling and stiffness, but was painless and self-limiting. It is suggested that this phenomenon results from disordered vasoregulation in diabetic neuropathy, and is linked to the processes which underlie diabetic neuropathic osteoarthropathy (Charcot foot), as well as disorders such as complex regional pain syndrome-1 (CRPS-1, reflex sympathetic dystrophy) and erythromelalgia. As self-limiting vasodilation may be not uncommon in distal symmetrical neuropathies, but unrecognized because the phenomenon has not been named, the terms 'neuropathic erythromelia' or 'Mitchell's syndrome' are proposed. The adoption of either of these names may lead to earlier diagnosis and prevent inappropriate investigation and treatment.