Differences in skin sympathetic involvements between two chronic autonomic disorders: multiple system atrophy and pure autonomic failure.
OBJECTIVE
Certain stimuli evoke increased sweat secretion (sympathetic sweat response; SSwR) and reduced skin blood flow (skin vasomotor reflex; SkVR) in the palm/sole. We evaluated SSwR and SkVR in patients with multiple system atrophy (MSA) and pure autonomic failure (PAF).


METHODS
SSwR and SkVR on the palm in response to deep inspiration and mental arithmetic were recorded in 11 MSA patients, 11 PAF patients, and 11 healthy controls. In addition, the head-up tilt test was performed, and the coefficient of variation of R-R intervals (CV(R-R)) was obtained.


RESULTS
SSwR amplitudes were significantly lower in the MSA and PAF patients than the controls. SkVR amplitudes in the PAF patients were significantly lower than the controls, but preserved in the MSA patients. In head-up tilt tests, all MSA and PAF patients showed orthostatic hypotension, with similar severity. CV(R-R) was low in the MSA and PAF patients, but a significant difference was found only between the PAF and control groups.


CONCLUSIONS
In the MSA patients, SkVR was preserved, but SSwR was diminished. In the PAF patients, both SkVR and SSwR were attenuated. The combination of SkVR and SSwR tests may differentiate MSA and PAF.
Asahina
Masato
M
Department of Neurology, Chiba University School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8670, Japan. asahina@faculty.chiba-u.jp
Akaogi
Yuichi
Y
Yamanaka
Yoshitaka
Y
Koyama
Yu
Y
Hattori
Takamichi
T
D000368:Aged; D001342:Autonomic Nervous System Diseases / Q000503:physiopathology*; D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D005260:Female; D005438:Fludrocortisone / Q000627:therapeutic use; D006801:Humans; D007024:Hypotension, Orthostatic / Q000188:drug therapy / Q000209:etiology; D008297:Male; D008433:Mathematics; D008606:Mental Processes / Q000502:physiology; D008875:Middle Aged; D008879:Midodrine / Q000627:therapeutic use; D019578:Multiple System Atrophy / Q000503:physiopathology*; D010300:Parkinson Disease / Q000503:physiopathology; D011724:Pyridazines / Q000627:therapeutic use; D012016:Reference Values; D012867:Skin / Q000098:blood supply / Q000293:injuries* / Q000503:physiopathology; D013546:Sweating / Q000502:physiology; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D013566:Sympathomimetics / Q000627:therapeutic use
D011724:Pyridazines; D013566:Sympathomimetics; D008879:Midodrine; C027784:amezinium; D005438:Fludrocortisone