PATTERNS OF RECOVERY IN THE GUILLAIN-BARRE-SYNDROMES

Clinical, electrodiagnostic, and pathologic studies indicate that the Guillain-Barre syndromes (GBSs) include both primary demyelinating and primary axonal forms. The axonal forms are usually thought to have a poorer prognosis, with less chance for rapid or complete recovery, In northern China, epidemics of one axonal form, acute motor axonal neuro pathy (AMAN), occur annually in the summer. Autopsy studies in some fa tal cases have demonstrated wallerian-like degeneration of motor roots and motor fibers in the peripheral nerves. Recovery of such patients would require axonal regeneration along the entire length of the nerve fiber, In a 2-year prospective study of GBS at a single hospital in n orthern China, 42 patients were classified as having either AMAN (32 p atients), acute inflammatory demyelinating polyneuropathy (AIDP) (8 pa tients), or as undetermined (2 patients) by electrodiagnostic criteria . Their recoveries were monitored clinically. The recovery times of AM AN and AIDP patients were similar: the median time to regain the abili ty to walk 5 meters with assistance was 31 days for patients classifie d as having AMAN and 32 days for those classified as having AIDP. Thes e rapid recovery times are incompatible with severe wallerian degenera tion of the ventral roots and motor nerve fibers, The rapid recoveries observed in AMAN patients could be explained by relatively quickly re versible immune-mediated changes at nodes of Ranvier in motor fibers, by degeneration and regeneration of intramuscular motor nerve terminal s, or both.