The neurophysiological mechanisms for persisting impairment of motor function after Guillain-Barr syndrome (GBS) were assessed in 37 unselected patients 1- 13 years after diagnosis. For evaluation of reinnervation a...The neurophysiological mechanisms for persisting impairment of motor function after Guillain-Barr syndrome (GBS) were assessed in 37 unselected patients 1- 13 years after diagnosis. For evaluation of reinnervation and axonal loss, macroelectromyography (macro-EMG) including measurement of fiber density (FD) was performed. Data from neuropathy symptom score, neuropathy disability score, nerve conduction studies, and quantitative sensory examination were ranked and s ummed to a neuropathy rank sum score (NRSS). The isokinetic muscle strength at t he ankle was measured. Signs of axonal loss with increase of either macro motor unit potential (macro-MUP) amplitude or FD occurred in 76% of patients. The macro-MUP amplitude correlated with muscle strength and with NRSS. Patients wi th evidence of residual neuropathy had increased macro-MUP amplitude and FD as well as decreased muscle strength compared to patients without evidence of res idual neuropathy. We conclude that axonal loss takes place in a substantial numb er of GBS patients and is associated with permanent muscle weakness caused by in sufficient reinnervation. Possible patterns of pathology are discussed in relati on to the macro-EMG findings.展开更多
文摘The neurophysiological mechanisms for persisting impairment of motor function after Guillain-Barr syndrome (GBS) were assessed in 37 unselected patients 1- 13 years after diagnosis. For evaluation of reinnervation and axonal loss, macroelectromyography (macro-EMG) including measurement of fiber density (FD) was performed. Data from neuropathy symptom score, neuropathy disability score, nerve conduction studies, and quantitative sensory examination were ranked and s ummed to a neuropathy rank sum score (NRSS). The isokinetic muscle strength at t he ankle was measured. Signs of axonal loss with increase of either macro motor unit potential (macro-MUP) amplitude or FD occurred in 76% of patients. The macro-MUP amplitude correlated with muscle strength and with NRSS. Patients wi th evidence of residual neuropathy had increased macro-MUP amplitude and FD as well as decreased muscle strength compared to patients without evidence of res idual neuropathy. We conclude that axonal loss takes place in a substantial numb er of GBS patients and is associated with permanent muscle weakness caused by in sufficient reinnervation. Possible patterns of pathology are discussed in relati on to the macro-EMG findings.
