Focal (segmental) dyshidrosis in syringomyelia

The features or mechanisms of dyshidrosis have not been sufficiently clarif ied. Neither has the difference between hyperhidrosis and hypohidrosis. To clarify the features and mechanisms of dyshidrosis (hyperhidrosis and hypoh idrosis) in syringomyelia, the clinical features focusing on hidrosis of 30 patients with syringomyelia and Chiari malformation located from a syringo myelia database were prospectively analysed. The patients were classified i nto three groups: eight patients (26.7%) had segmental hypohidrosis, 10 (33 .3%) had segmental hyperhidrosis, and 12 (40.0%) had normohidrosis. We foun d that the Karnofsky functional status for the hyperhydrosis and normohidro sis groups were significantly higher than for the hypohidrosis group (p=0.0 012), with no significant differences between the hyperhidrosis and normohi drosis groups. The duration from the onset of syringomyelia to the current dyshidrosis was significantly longer in the hypohidrosis group than in the hyperhidrosis group (p=0.0027). A significant correlation was identified be tween the duration from the onset of syringomyelia to the time at study and the performance score (r=-0.599, p=0.0003). The results substantiate previ ous hypotheses that in its early stage syringomyelia causes segmental hyper activity of the sympathetic preganglionic neurons, and hyperactivity of the se gradually subsides as tissue damage progresses. Focal hyperhidrosis may be regarded as a hallmark of a relatively intact spinal cord, as well as no rmohidrosis.