Alternating monomeric paresis with decreased skin temperature and hyperhidrosis in a case of thoracolumbar myelopathy.

The patient, a Japanese girl with a history suggestive of diffuse encephalitis or acute disseminated encephalomyelitis, developed weakness of the right lower limb accompanied by excessive sweating and decreased skin temperature. Magnetic resonance imaging of the thoracolumbar cord showed abnormal signal intensity with syrinx formation mainly at T12 to L1 vertebral level. Paresis and excessive sweating subsided within 3 to 4 months, but recovery of vasomotor function was delayed. Several weeks later, weakness and skin temperature reduction reappeared on the left side without hyperhidrosis, but responded well to oral prednisolone. The patient showed no recurrence during the subsequent 7 years, and the intramedullary lesion could not be seen with repeated spinal magnetic resonance imaging.