Electrodiagnostic abnormalities in 113 consecutive patients with Guillain-Barre syndrome
A. H. Ropper, E. F. Wijdicks and B. T. Shahani
Clinical Neurophysiology Laboratory, Massachusetts General Hospital, Boston 02114.
We performed electrodiagnostic tests on 113 consecutive patients with acute
Guillain-Barre syndrome (103 within 3 weeks of onset). The most common
motor conduction abnormalities were proximal conduction block alone (27%),
proximal block associated with a distal lesion (27%), and generalized
slowing (22%). Other combinations of abnormalities each occurred in fewer
than 10% of patients. Thirty-seven percent of patients initially had normal
sensory nerve conduction study results, most often in association with
proximal conduction block. The characteristic early electrodiagnostic
changes in Guillain-Barre syndrome were often present when cerebrospinal
fluid protein concentration was still normal. Extensive early fibrillations
occurred in 10 patients, 6 of whom recovered well. Patients with early
generalized slowing of motor nerve conduction velocity, combined
abnormalities, or low muscle action potential amplitudes in ulnar, median,
and peroneal nerves generally, but not always, had poorer outcomes than
patients with conduction block in one nerve segment. There was no
consistent relationship between results of electrophysiologic studies and
overall clinical grade or limb power, except that none of the patients with
an isolated proximal block had virtual or complete paralysis in the same
limb.
