Introduction: Hyperhidrosis may result from brain, spinal cord or peripheral nervous system injuries. We report the case of a 26-year-old patient who presented with sensorial disorders and focal hyperhidrosis of the right hand.
Observation: MRI revealed multiple lesions very suggestive of active demyelinization. A lesion in the left paramedian posterior portion of the pons was enhanced after gadolinium infusion. The diagnosis of multiple sclerosis was suggested by MRI data and oligoclonal IgG bands on cerebrospinal fluid electrophoresis.
Conclusions: Focal hyperhidrosis may be due to a lesion of the crossed sympathetic inhibitory tract. Although autonomic dysfunction is common during the late course of multiple sclerosis this case is, to our knowledge, the first report of focal hyperhidrosis revealing multiple sclerosis.