Asymmetric sweating in a child with multiple sclerosis.

A 10-year-old male with multiple sclerosis complained of excessive sweating on the right side of the forehead and shoulder on relapse 3 months after the onset of multiple sclerosis. Because the neurologic evaluation revealed no abnormalities in the sudomotor function, it is likely that the hyperhidrosis resulted from a lesion in the central or preganglionic sympathetic nervous system. Magnetic resonance imaging demonstrated a high-intensity lesion involving the left hypothalamus on T(2)-weighted imaging. Thus hypothalamic involvement might be the reason for the hyperhidrosis in this patient.