Idiopathic unilateral localized hyperhidrosis.

Sir, Unilateral localized hyperhidrosis is an uncommon condition with diverse causes. Lesions affecting any part of the sympathetic nervous system are often encountered as the cause of the disease and in a few cases enlarged sweat glands have been shown; these cases have been regarded as a type of eccrine naevi. There are also some cases in which the underlying pathology cannot be determined, and these are considered idiopathic. We describe here another case of idiopathic unilateral localized hyperhidrosis; a disorder with an aetiology still waiting to be clari®ed.