Discrimination of spinal and bulbar muscular atrophy from amyotrophic lateral sclerosis using sensory nerve action potentials
Article first published online: 12 JAN 2012
Copyright © 2011 Wiley Periodicals, Inc.
Muscle & Nerve
Volume 45, Issue 2, pages 169–174, February 2012
How to Cite
Hama, T., Hirayama, M., Hara, T., Nakamura, T., Atsuta, N., Banno, H., Suzuki, K., Katsuno, M., Tanaka, F. and Sobue, G. (2012), Discrimination of spinal and bulbar muscular atrophy from amyotrophic lateral sclerosis using sensory nerve action potentials. Muscle Nerve, 45: 169–174. doi: 10.1002/mus.22291
- Issue published online: 12 JAN 2012
- Article first published online: 12 JAN 2012
- Accepted manuscript online: 1 SEP 2011 07:41AM EST
- Ministry of Education, Culture, Sports, Science, and Technology of Japan, and the Ministry of Health, Labor, and Welfare of Japan
- amyotrophic lateral sclerosis;
- nerve conduction study;
- sensory impairment;
- sensory nerve action potential;
- spinal and bulbar muscular atrophy
Spinal and bulbar muscular atrophy (SBMA) and amyotrophic lateral sclerosis (ALS) are motor neuron diseases. Sensory impairment is sometimes observed, and electrophysiological involvement has been described in the sensory nerves of SBMA patients. We hypothesized that a sensory nerve conduction study (NCS) could be used to discriminate SBMA from ALS.
We compared the results from NCSs in a total of 120 SBMA cases confirmed by genetic analysis, 188 ALS cases, and 50 normal subjects.
Sensory nerve action potential (SNAP) amplitudes of the SBMA group were significantly lower than in the ALS and control groups. In addition, receiver-operating characteristic curve analysis for SNAP amplitude showed that a cut-off value of 13.8 μV for median, 10.7 μV for ulnar, and 9.9 μV for sural nerve best discriminated SBMA from ALS.
The specific decrease of SNAP amplitude in SBMA provides another useful tool for the differential diagnosis of motor neuron diseases. Muscle Nerve, 2012