Criteria for the diagnosis of Guillain-Barré syndrome are reaffirmed. Electrodiagnostic criteria are expanded and specific detail added.

Guillain-Barré syndrome has been considered to be primarily an acute inflammatory demyelinating polyneuropathy (AIDP). Our experience with Guillain-Barré syndrome in northern China differs from the traditional concept. Electrophysiologically and pathologically, most of our patients have motor axonal degeneration with minimal cellular inflammation, which we have termed 'acute motor axonal neuropathy' (AMAN). The current studies were undertaken to characterize prospectively the clinical, electrophysiological, and serological features of Guillain-Barré syndrome, defined clinically, in northern China. In 1991 and 1992, we characterized by electrodiagnostic criteria 129 Chinese patients with Guillain-Barré syndrome. The AMAN form was present in 65% of patients, the AIDP form in 24% and 11% were unclassifiable. For the 38 patients who presented from January to October, 1992, we performed serological assays for antibodies to Campylobacter jejuni and to glycolipids. Of these 38 patients, 55% had AMAN, 32% had AIDP and 13% were unclassifiable. Sixty-six percent of the 38 had serological evidence of recent C. jejuni infection as compared with 16% of village controls (P = 0.001). Seventy-six percent of AMAN patients and 42% of AIDP patients were seropositive. IgG anti-GM1 antibodies were more frequent in Guillain-Barré syndrome patients compared with village controls (42% versus 6%; P < 0.01). However, no statistically significant correlations were found between the pattern of disease, AMAN or AIDP, anti-glycolipid antibodies, or C. jejuni antibodies. Based on electrophysiological criteria, Guillain-Barré syndrome in northern China can be divided into two predominant forms: AIDP and AMAN. The AMAN form is more common and predominates in the yearly summer outbreaks of Guillain-Barré syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

In northern China, annual epidemics of acute-onset flaccid paralysis diagnosed clinically as Guillain-Barré syndrome have been recognized for at least 20 years. On the basis of an historical analysis of more than 3,200 patients, distinctive features include most cases occurring during the summer months among children and young adults, most of whom reside in rural areas. Of 90 patients with acute flaccid paralysis, 88 had a distinctive pattern that shares clinical and cerebrospinal fluid findings with demyelinating Guillain-Barré syndrome, but that differs from Guillain-Barré syndrome physiologically and pathologically. The clinical course is marked by rapidly progressive ascending tetraparesis, often with respiratory failure, but without fever, systemic illness, or sensory involvement. Cerebrospinal fluid is acellular, and elevations of protein content occur in the second or third week of illness. Electrodiagnostic studies show normal motor distal latencies and limb conduction velocities, but reduced compound muscle action potential amplitudes. Sensory nerve action potentials and, when elicitable, F waves are within the range of normal. Recovery is usually good. Autopsy studies have shown Wallerian-like degeneration of motor fibers. These studies establish that this is a distinctive syndrome, distinguishable from poliomyelitis and demyelinating Guillain-Barré syndrome.

The acute motor axonal neuropathy (AMAN) form of the Guillain-Barre syndrome is a paralytic disorder of abrupt onset characterized pathologically by motor nerve fiber degeneration of variable severity and by sparing of sensory fibers. There is little demyelination or lymphocytic inflammation. Most cases have antecedent infection with Campylobacter jejuni and many have antibodies directed toward GM1 ganglioside-like epitopes, but the mechanism of nerve-fiber injury has not been defined. In 7 fatal cases of AMAN, immunocytochemistry demonstrated the presence of IgG and the complement activation product C3d bound to the axolemma of motor fibers. The most frequently involved site was the nodal axolemma, but in more severe cases IgG and C3d were found within the periaxonal space of the myelinated internodes, bound to the outer surface of the motor axon. These results suggest that AMAN is a novel disorder caused by an antibody- and complement-mediated attack on the axolemma of motor fibers.

We describe five patients with a chronic asymmetric sensorimotor neuropathy most pronounced in the upper extremities with focal involvement of individual nerves. Diagnosis was established by electrophysiologic evidence of persistent multifocal conduction block. Sural nerve biopsy in three patients showed primarily demyelinating-remyelinating changes with varying degrees of fiber loss. Two patients had acute optic neuritis, indicating that the disorder was not always restricted to the peripheral nervous system. Two patients treated with corticosteroids improved, whereas three untreated patients had static deficits or steady progression of symptoms. Chronic multifocal demyelinating neuropathy with persistent conduction block seems to be a variant of chronic acquired demyelinating polyneuropathy and may be immunologically mediated.