Department of Neurology, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Shimotsuga, Tochigi, Japan.
Brain. 2010 Oct;133(10):2897-908. doi: 10.1093/brain/awq260. Epub 2010 Sep 20.
Guillain-Barré syndrome is divided into two major subtypes, acute inflammatory demyelinating polyneuropathy and acute motor axonal neuropathy. The characteristic electrophysiological features of acute motor axonal neuropathy are reduced amplitude or absence of distal compound muscle action potentials indicating axonal degeneration. In contrast, autopsy study results show early nodal changes in acute motor axonal neuropathy that may produce motor nerve conduction block. Because the presence of conduction block in acute motor axonal neuropathy has yet to be fully recognized, we reviewed how often conduction block occurred and how frequently it either reversed or was followed by axonal degeneration. Based on Ho's criteria, acute motor axonal neuropathy was electrodiagnosed in 18 patients, and repeated motor nerve conduction studies were carried out on their median and ulnar nerves. Forearm segments of these nerves and the across-elbow segments of the ulnar nerve were examined to evaluate conduction block based on the consensus criteria of the American Association of Electrodiagnostic Medicine. Twelve (67%) of the 18 patients with acute motor axonal neuropathy had definite (n=7) or probable (n=5) conduction blocks. Definite conduction block was detected for one patient (6%) in the forearm segments of both nerves and probable conduction block was detected for five patients (28%). Definite conduction block was present across the elbow segment of the ulnar nerve in seven patients (39%) and probable conduction block in two patients (11%). Conduction block was reversible in seven of 12 patients and was followed by axonal degeneration in six. All conduction blocks had disappeared or begun to resolve within three weeks with no electrophysiological evidence of remyelination. One patient showed both reversible conduction block and conduction block followed by axonal degeneration. Clinical features and anti-ganglioside antibody profiles were similar in the patients with (n=12) and without (n=6) conduction block as well as in those with (n=7) and without (n=5) reversible conduction block, indicating that both conditions form a continuum; a pathophysiological spectrum ranging from reversible conduction failure to axonal degeneration, possibly mediated by antibody attack on gangliosides at the axolemma of the nodes of Ranvier, indicating that reversible conduction block and conduction block followed by axonal degeneration and axonal degeneration without conduction block constitute continuous electrophysiological conditions in acute motor axonal neuropathy.
格林-巴利综合征分为两个主要亚型，急性炎症性脱髓鞘性多发性神经病和急性运动轴索性神经病。急性运动轴索性神经病的特征性电生理学特征是远端复合肌肉动作电位幅度降低或缺失，提示轴索变性。相比之下，尸检研究结果显示急性运动轴索性神经病早期存在神经结改变，可能导致运动神经传导阻滞。由于急性运动轴索性神经病中存在传导阻滞尚未得到充分认识，我们回顾了传导阻滞发生的频率，以及它是逆转还是随后发生轴索变性。根据 Ho 的标准，对 18 例急性运动轴索性神经病患者进行电诊断，并对其正中神经和尺神经进行重复运动神经传导研究。根据美国电诊断医学协会的共识标准，检查这些神经的前臂段和尺神经的肘上段，以评估传导阻滞。18 例急性运动轴索性神经病患者中，12 例（67%）有明确（n=7）或可能（n=5）的传导阻滞。在两条神经的前臂段均发现 1 例患者（6%）存在明确的传导阻滞，在 5 例患者（28%）中发现可能的传导阻滞。7 例患者（39%）尺神经肘上段存在明确的传导阻滞，2 例患者（11%）存在可能的传导阻滞。12 例患者中有 7 例传导阻滞可逆转，6 例随后发生轴索变性。所有的传导阻滞在 3 周内均消失或开始缓解，无脱髓鞘的电生理证据。1 例患者同时出现可逆转的传导阻滞和随后的轴索变性。有（n=12）和无（n=6）传导阻滞的患者以及有（n=7）和无（n=5）可逆转传导阻滞的患者的临床特征和抗神经节苷脂抗体谱相似，表明这两种情况构成一个连续体；一种可能由抗神经节苷脂抗体攻击郎飞结轴索膜引起的病理生理学谱，从可逆转的传导失败到轴索变性，表明可逆转的传导阻滞和随后的轴索变性以及无传导阻滞的轴索变性在急性运动轴索性神经病中构成连续的电生理条件。
