An electrophysiological classification associated with Guillain–Barré syndrome outcomes

Abstract

Guillain-Barré syndrome (GBS) is an acute, post-infectious, inflammatory, autoimmune peripheral neuropathy with a highly diverse clinical course and outcome. We classified GBS on the basis of patients' first nerve conduction and validated this system to be associated with outcome on the basis of electrophysiological characteristics during the acute phase of GBS. We retrospectively evaluated 40 GBS patients who underwent their first electrophysiological study within 14 days of onset and classified GBS into four patterns: (1) acute inflammatory demyelinating polyneuropathy (AIDP) pattern with sensory nerve conduction abnormalities (motor-sensory AIDP: MS-AIDP), (2) AIDP pattern without sensory nerve conduction abnormalities (motor AIDP: M-AIDP), (3) acute motor axonal neuropathy (AMAN) pattern, and (4) minor abnormalities pattern. We compared the clinical, electrophysiological, and laboratory findings between groups and determined subgroups associated with poor outcome. The MS-AIDP and AMAN patterns more frequently exhibited prolonged recovery compared with the M-AIDP and minor abnormalities patterns and were associated with prolonged recovery (specificity, 100%; sensitivity, 73%; P < 0.001). The period of inability to walk independently was significantly longer in the MS-AIDP and AMAN patterns than in the M-AIDP and minor abnormalities patterns (median 85 vs. 10 days; P < 0.001). In conclusion, our classification of GBS using a single nerve conduction study in the early phase of disease is associated with outcomes. This classification can be used to counsel individual patients and guide decision-making with respect to treatment.

Serial electrophysiological findings in Guillain–Barré syndrome not fulfilling AIDP or AMAN criteria

“…We previously demonstrated that the pathophysiology of the ''M-AIDP pattern'' is AMAN with RCF, that the pathophysiology of the ''MS-AIDP pattern'' is true AIDP, and that the pathophysiology of the ''AMAN pattern'' is AMAN with axonal degeneration [16]. The findings of the present study demonstrate the pathophysiology of unclassified patients is AMAN with RCF.…”

“…To resolve this issue, we previously focused on the fact that AMAN patients with both axonal degeneration and RCF have common clinical features because of a shared disease spectrum [2-5, 28, 32], with the absence of clinical and electrophysiological involvement of sensory nerve, while the involvement of sensory nerve are typically present in AIDP patients. Thereby, we previously demonstrated the utility of classifying GBS into ''M-AIDP,'' ''MS-AIDP,'' and ''AMAN'' patterns for the determination of detailed pathophysiology including AMAN with RCF, as follows: the ''M-AIDP pattern'' corresponds to AMAN with RCF; the ''MS-AIDP pattern'' corresponds to true AIDP; and the ''AMAN pattern'' corresponds to AMAN with axonal degeneration [16]. These findings prompted us to classify GBS into four patterns according to initial electrophysiological findings and compare and analyze serial DML findings between all four patterns.…”

“…Patients were considered to have sensory nerve conduction abnormalities when the sensory nerve action potential (SNAP) amplitude was\50 % of the lower limit of normal in at least two nerves [24]. We further electrophysiologically classified the AIDP pattern according to the presence or absence of sensory nerve conduction abnormalities, which we termed MS-AIDP and M-AIDP patterns, respectively [16]. In the present study, the electrophysiological pattern of AIDP and AMAN were, respectively, expressed as ''AIDP pattern (M-AIDP and MS-AIDP pattern)'' and ''AMAN pattern'' as electrophysiological patterns and disease subtypes may not be equivalent.…”

“…Aside from the utility of serial studies, we previously demonstrated the utility of electrophysiologically classifying the AIDP pattern further according to the presence or absence of sensory nerve conduction abnormalities, which we termed motor-sensory AIDP (MS-AIDP) and motor AIDP (M-AIDP) patterns, respectively [16]. The presence of RCF demonstrates limitations of conventional classification systems, where AMAN patients with RCF may be incorrectly classified as having the AIDP pattern because of conduction abnormalities such as prolonged DML, and patients classified as having the AIDP pattern may include patients with two different disease entities: AMAN with RCF and true AIDP.…”

Unexpected Rapid Improvement and Neurogenic Stunned Myocardium in a Patient With Acute Motor Axonal Neuropathy

“…8,9,28 It has recently been hypothesized that this dichotomy may be related to 2 distinct pathological mechanisms, with some patients experiencing extensive axonal degeneration, and others undergoing reversible conduction failure related to the presence of anti-GM1 antibodies. 29,30 Here we describe a case of a 27-year-old woman who developed AMAN-type GBS characterized by tetraplegia, respiratory failure, and areflexia after M. pneumoniae infection. Antiganglioside antibodies including anti-GM1 were present in our patient's serum; she exhibited neurogenic stunned myocardium and profound autonomic dysfunction, and she recovered rapidly with plasmapheresis (PLEX) despite the severity of her initial presentation.…”