A case of human botulism has been studied with neurophysiological tests. The concentric needle electromyography showed short, small and polyphasic potentials. Supramaximal stimulation of the ulnar nerve at 2 Hz evoked a compound muscle action potential of reduced amplitude, without further changes in the following stimuli. After maximum effort the compound muscle action potential amplitude increased up to 41%. The increment turned out to be more significant when the ratio of the areas between the signal envelope and baseline of the potential before and after maximum effort was considered. At 20 Hz stimulation the compound muscle action potential amplitude showed an increment up to 80%. Single fiber electromyography revealed 11 abnormal jitters out of 21 couples of potentials, 4 of them with blockings. Motor and sensory conductions were normal. Neurophysiological tests were repeated to check the regression of the disorder. The neurophysiological tests adopted are compared and discussed.
|Number of pages||9|
|Journal||Electromyography and Clinical Neurophysiology|
|Publication status||Published - 1983|
ASJC Scopus subject areas
- Clinical Neurology