Neuroimmunology
Autoantibodies: mechanism and testing
Dec. 20, 2024
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Acute inflammatory demyelinating polyradiculoneuropathy is the most frequent pattern of Guillain-Barré syndrome encountered in North America and Europe. In this review, the author explains the clinical features, criteria for diagnosis, advances in the pathogenesis, and treatment of acute inflammatory demyelinating polyradiculoneuropathy. In addition, variants of Guillain-Barré syndrome and related disorders are briefly discussed. This update includes some studies on biological markers in this disorder, and information on COVID infection and Guillain-Barré syndrome.
• Acute inflammatory demyelinating polyradiculoneuropathy is the most frequent pattern of Guillain-Barré syndrome encountered in North America and Europe. | |
• Molecular mimicry and ganglioside antibodies play an important role in the pathogenesis of some variants of Guillain-Barré syndrome (eg, acute motor axonal neuropathy). | |
• Intravenous immunoglobulins or plasma exchange are proven effective therapy for Guillain-Barré syndrome. | |
• A task force of the Peripheral Nerve Society and European Academy of Neurology recommends against a second course of intravenous immunoglobulins in patients with a poor prognosis. |
Acute inflammatory demyelinating polyradiculoneuropathy is an inflammatory disease of the peripheral nervous system characterized by lymphocytic and macrophagic infiltration with destruction of myelin. The condition is often designated as the Landry-Guillain-Barré-Strohl syndrome or Guillain-Barré syndrome (GBS) in recognition of the descriptions provided by these authors. An acute, ascending, predominantly motor paralysis with respiratory failure and death was first reported by Landry in 1859. In 1916 G Guillain and JA Barré, then French army neurologists, along with A Strohl reported two patients with acute polyradiculoneuritis and introduced the concept of "albuminocytologic dissociation" in the cerebrospinal fluid as a laboratory marker to distinguish this disorder from other neuropathies and from poliomyelitis. An approximate translation of the opening sentence in their report is:
We bring to attention in the present note a clinical syndrome that we have observed in two individuals, a syndrome characterized by motor difficulty, abolition of deep tendon reflexes with preservation of cutaneous reflexes, paresthesias without objective sensory loss, pain on deep palpation of large muscles, minor modifications in electrical reactions of nerve and muscle, and increased albumin in the cerebrospinal fluid with most notably, absence of cellular reaction (albuminocytologic dissociation). |
Acute inflammatory demyelinating polyneuropathy. Guillain-Barré syndrome is now recognized to be a diverse disorder that can be divided into several patterns based on the predominant mode of fiber injury (demyelinating vs. axonal) and on nerve fibers involved (motor, sensory and motor, cranial). The most frequent pattern in Western countries is the acute inflammatory demyelinating polyneuropathy. The major complaint is weakness, which usually evolves symmetrically over a period of several days. Evolution is complete after 2 weeks in 50% of cases, after 3 weeks in over 80%, and after 4 weeks in over 90% (02). In most instances, weakness is noticed initially in the legs, but it can begin in the arms or the face. The severity of weakness varies from mild gait difficulty to total paralysis with death from respiratory failure. Aside from facial diplegia, which is found in at least half of the cases, involvement of extraocular muscles has been described. Other symptoms include pain and muscle aches, which occur in 30% to 55% of cases. Early in the course of illness, subjective dysesthesias and paresthesias are common. At later times, objective sensory loss can be demonstrated in three-fourths of cases. Tendon reflexes are usually abolished or diminished. Dysautonomia is common and can manifest as heart rate or blood pressure instability, blood pressure fluctuations, pupillary dysfunction, and bowel or bladder dysfunction (02). Acute inflammatory demyelinating polyneuropathy is a monophasic illness, though treatment-related fluctuations or relapses occur in a minority of patients (37).
Variants of Guillain-Barré syndrome. Axonal involvement in Guillain-Barré syndrome has traditionally been considered secondary to severe demyelination until Feasby and colleagues called attention to a small group of patients that had primary axonal degeneration, now termed acute motor-sensory axonal neuropathy. These patients typically have severe, fulminant paralysis, sensory loss, and incomplete recovery. Autopsy findings demonstrate axonal degeneration without demyelination and with minimal inflammation (12).
In comparison, acute motor axonal neuropathy, also called “Chinese paralytic syndrome,” is characterized by acute weakness or paralysis without sensory loss and is closely associated with antecedent Campylobacter infection. Patients with acute motor axonal neuropathy usually have a more rapid progression and an earlier nadir than those with acute inflammatory demyelinating polyneuropathy (16). A subset of patients with acute motor axonal neuropathy recovers rapidly. Electrodiagnostic studies confirm the selective involvement of motor fibers with preservation of sensory responses. High titers of IgG anti-GM1, GM1b, or GD1a antibodies are more common in the acute motor axonal neuropathy than in acute inflammatory demyelinating polyneuropathy (17). These antibodies cause a pathophysiological spectrum ranging from reversible conduction block to axonal degeneration of motor fibers (24).
A third disorder considered as a Guillain-Barré syndrome variant is Fisher syndrome, which is characterized by ophthalmoplegia, ataxia, areflexia, and association with antibodies that recognize the ganglioside GQ1b, GT1a, or GD3 (49). Facial nerves may be involved in addition to ocular motor nerves, but limb weakness is infrequent. Another condition that is associated with anti-GQ1b antibody is Bickerstaff brainstem encephalitis, which is characterized by a disturbance of consciousness, hyperreflexia, ataxia, and ophthalmoplegia (31). Brain MRI is abnormal in 30% of these patients. The prognosis for recovery is good. Some patients have concomitant limb weakness and electrodiagnostic evidence of an axonal subtype of Guillain Barré syndrome (31). The immunological profile in Bickerstaff brainstem encephalitis and Fisher syndrome suggests common pathogenetic mechanisms, but the nosological relationship between these disorders remains controversial.
Other variants of Guillain Barré syndrome include pharyngeal-cervical-brachial variant, acute pandysautonomia, and sensory Guillain-Barré syndrome. The pharyngeal-cervical-brachial variant manifests as dysphagia, neck and shoulder muscle weakness, and may be associated with IgG anti-GT1a antibody (22). In the sensory form of Guillain-Barré syndrome, patients have acute sensory loss but no weakness although demyelinating features are present in motor nerve conduction studies (32). Acute/subacute pandysautonomia without concomitant motor or sensory deficits is rare and is associated with antibody against ganglionic acetylcholine receptor in some cases.
Two sets of criteria are often used for the diagnosis of Guillain-Barré syndrome: NINDs criteria and Brighton collaboration (02; 39). The Brighton Collaboration Consensus criteria and recently published guideline on the diagnostic criteria are listed in tables 1 and 2 (45).
Diagnostic criteria |
Level of diagnostic certainty | |||
1 |
2 |
3 | ||
Bilateral and flaccid limb weakness |
+ |
+ |
+ | |
Decreased or absent reflexes in weak limbs |
+ |
+ |
+ | |
Monophasic course and interval between onset and nadir of 12 hr to 4 weeks |
+ |
+ |
+ | |
Cytoalbuminologic dissociation in CSF |
+ |
+/-* |
- | |
Nerve conduction studies consistent with Guillain Barré syndrome |
+ |
+/-** |
- | |
Absence of alternative diagnosis for weakness |
+ |
+ |
+ | |
|
Features required | |
• Progressive weakness of arms and legs | |
• Tendon reflexes absent or decreased in affected limbs | |
• Progressive worsening for no more than 4 weeks | |
Features strongly supportive of the diagnosis | |
• Relative symmetry | |
• Relatively mild /absent sensory symptoms and signs | |
• Cranial nerve involvement especially bilateral facial weakness | |
• Autonomic dysfunction | |
• Respiratory insufficiency (due to muscle weakness) | |
• Pain (muscular or radicular in back or limb) | |
• Recent history of infection (< 6 weeks), (possibly also surgery) | |
Laboratory findings that support the diagnosis | |
• CSF: increased protein; normal protein does not rule out diagnosis; (WBC < 5 white cells/mm3) | |
• Blood: Anti-GQ1b antibodies usually present in Miller Fisher syndrome | |
• Electrodiagnosis: Nerve conduction studies (NCS) consistent with polyneuropathy. NCS may be normal during first few days of disease. | |
|
Recovery ranges from complete and rapid to slow with significant residual disability, depending on the relative proportions of segmental demyelination and axonal degeneration in patients with acute inflammatory demyelinating polyradiculoneuropathy. Most patients recover spontaneously with 80% ambulating independently at 6 months after disease onset (07). Between 3% and 8% of patients die from complications. Permanent disabling weakness, imbalance, or sensory loss occurs in 5% to 10%, whereas mild residual signs of neuropathy persist in 50% of patients. Little or no further recovery can be expected after 2 years.
Approximately 3% of patients with acute inflammatory demyelinating polyradiculoneuropathy suffer one or more recurrences. The clinical symptoms of relapses do not differ from those of the acute monophasic form of the disease. Each episode is characterized by rapid onset of symptoms over a few days, with subsequent complete or near-complete recovery. In patients with multiple relapses, nerves may become palpably enlarged. Such cases are to be distinguished from chronic inflammatory polyradiculoneuropathy, which evolves over many weeks, months, or years.
A 40-year-old nondiabetic woman presented to the emergency room with weakness of her legs that had started 5 to 6 days earlier and had begun to involve her upper extremities. Tingling and numbness of her toes and fingertips accompanied her symptoms. The patient had a flu-like illness 2 weeks before the onset of symptoms and no history of tick bites. Exam showed mild facial weakness, 4/5 strength in her proximal muscles and 3+/5 in her distal muscles, slightly decreased light touch and pinprick sensation distally, and absent deep tendon reflexes throughout. Her CSF showed elevated protein (150 mg/dl) with no cells. Nerve conduction studies showed normal compound motor action potential amplitudes, mildly slowed conduction velocities, but prolonged distal motor and F wave latencies. Her forced vital capacity was 2 L. She improved significantly after a course of plasmapheresis.
Acute inflammatory demyelinating polyradiculoneuropathy is thought to be a cell-mediated autoimmune disease of the peripheral nerves, based on lymphocytic inflammation and the analogy to experimental allergic neuritis. The latter is caused by CD4+ T cells against peripheral myelin peptides such as P2 and P0. The role of autoreactive T cells is supported by findings in a study using single cell RNA sequencing and T cell receptor sequencing (43). Sukenokova and colleagues have identified autoreactive T cells that target peripheral nerve myelin antigens P2, P0, and PMP22 in acute inflammatory demyelinating polyradiculoneuropathy, and they found that autoreactive TCRβ clonotypes were shared in the blood and CSF of these patients (43).
On the other hand, the role of humoral immunity involving antibodies against gangliosides is particularly evident in some variants of Guillain-Barré syndrome such as acute motor axonal neuropathy and Miller Fisher syndrome (17; 42; 15). Antibody attack against nodal antigens such as neurofascin, contactin, Caspr1, gliomedin, and neurofascin participates in the etiology of a small subset of Guillain-Barré syndrome, now considered as a different disease (autoimmune nodopathy) (45). Host factors might influence the susceptibility to develop Guillain-Barré syndrome. An association between HLA-DQ beta and DR-beta with susceptibility to acute inflammatory demyelinating polyradiculoneuropathy has been identified, but not with acute motor axonal neuropathy.
The pathological features in acute inflammatory demyelinating polyradiculoneuropathy consist of segmental demyelination and mononuclear cellular infiltration (23). Infiltrates are scattered at random along peripheral nerves, cranial nerves, nerve roots, dorsal root ganglia, and sympathetic ganglia. Sural nerve biopsies may show minimal abnormalities, perhaps reflecting the motor predominance of the disorder. Ultrastructurally, the earliest change in the myelin sheath is paranodal retraction resulting in a widened nodal gap. As the myelin sheath degenerates, ovoid formation and phagocytosis of myelin debris by macrophages become prominent. Axonal degeneration is seen in severe lesions, usually at sites of intense inflammatory changes. In the study by Koike and colleagues, macrophage-associated lesions can be seen at Node of Ranvier and at the internode, which seems to correspond to the pattern of complement deposition (23).
The acute motor axonal variant is characterized by lengthening of the nodal gap and distortion of the paranodal myelin by macrophages with paucity of lymphocyte infiltration, followed by Wallerian-like degeneration of motor fibers in the spinal roots and peripheral nerves in severe cases (11). The presence of either immunoglobulin G or complement activation products along the outer surface of Schwann cells or the axolemma provides further evidence for immune attack on acute inflammatory demyelinating polyradiculoneuropathy and acute motor axonal neuropathy, respectively (13; 14).
Electrophysiologically, conduction of impulses through areas of segmental demyelination is severely compromised. Conduction failure may occur at the junction between normally myelinated and demyelinated regions where the outward leakage current exceeds the safety factor for impulse conduction and where exposure of paranodal K+ channels leads to shortened action potential duration. This results in conduction block or temporal dispersion, which are the hallmarks of acquired demyelinating neuropathy. Axonal damage causes abnormal spontaneous activity and a decrease in the number of motor units. It is agreed that the most plausible explanations for weakness and sensory loss are conduction block and axonal degeneration.
Possible effector mechanisms of immune-mediated injury to peripheral nerves include cytotoxic T cell-mediated lysis, cytokines and free radicals, and antibody and complement-mediated mechanisms. The findings of increased serum concentrations of tumor necrosis factor-alpha and soluble E-selectin in patients with Guillain-Barré syndrome suggest that proinflammatory cytokines and adhesion molecules are involved in the pathogenesis of this disease. There is evidence supporting the role of costimulatory molecules in inflammatory neuropathies, likely by affecting the balance between effector T cells and regulatory T cells. This is exemplified by reports of Guillain-Barré syndrome and other inflammatory neuropathies precipitated by cancer immunotherapy with checkpoint inhibitors targeting CTLA-4 or PD-1 such as ipilimumab, pembrolizumab, or nivolumab (19; 18; 08).
Molecular mimicry has been postulated as a potential mechanism triggering autoimmunity. There is a report demonstrating antibodies against moesin in patients with cytomegalovirus-related acute inflammatory demyelinating polyradiculoneuropathy (38). Moesin is expressed in the Schwann cell processes at the nodes of Ranvier. For patients with antecedent diarrhea, the fact that lipopolysaccharide of C jejuni has a ganglioside-like structure suggests that acute motor axonal neuropathy and Miller Fisher syndrome involve molecular mimicry in their pathogenesis (48). Animal studies reveal that anti-ganglioside antibodies act not only on peripheral nerves but also at the motor nerve terminals. Effects of anti-ganglioside antibodies include: (1) complement-mediated disruption of Na+ channel clusters resulting in decreased Na+ current; (2) an alpha-latrotoxin-like effect on motor endplates resulting in dramatic release of acetylcholine followed by depletion; and (3) destruction of peri-synaptic Schwann cells and nerve terminals (35).
Guillain-Barré syndrome occurs in all parts of the world and at all ages, with an incidence ranging from one to two cases per 100,000 person-years, which increases with age (39). The oldest recorded patient was 95 years old. In most series, there is a modest male predominance. In North America and Europe, acute inflammatory demyelinating polyradiculoneuropathy is the most frequent pattern of Guillain-Barré syndrome. Approximately two-thirds of cases of acute inflammatory demyelinating polyradiculoneuropathy follow an infection, usually viral but sometimes mycoplasmal or bacterial (Campylobacter jejuni). The association of C jejuni with Guillain-Barré syndrome is interesting because these patients tend to develop acute motor axonal neuropathy in China (29). However, there appears to be other factors at play in the regional variation in the phenotype given that C jejuni is the most frequent antecedent infection (30%) across different regions in a prospective international cohort study (26).
Other infectious agents associated with the disease include cytomegalovirus; Epstein-Barr virus; smallpox-vaccinia; hepatitis B, C, or E; and HIV. During Zika virus outbreaks in French Polynesia and Latin America, there was an increase in the incidence of Guillain-Barré syndrome that manifested as acute motor axonal neuropathy or as acute inflammatory demyelinating polyradiculoneuropathy, and it was associated with reactivity to gangliosides (33). Association of COVID-19 pandemic with increased incidence of Guillain-Barré syndrome, predominantly the demyelinating type has been reported, although not all studies are in agreement (27).
Most vaccinations have no proven association with increased risk of Guillain-Barré syndrome. COVID-19 vaccines that utilize adenovirus vectors such as ChAdOx1 nCoV-19 (AstraZeneca) or Ad.26.COV2.S (Janssen) exhibit slightly increased risk of developing Guillain-Barré syndrome within 6 weeks of injection, albeit less than that occurring after COVID infection (20). In the United States, an outbreak of Guillain-Barré syndrome occurred in 1976 in conjunction with the swine flu vaccination program, with an excess risk of 10 cases per million vaccinations. In contrast, a surveillance study revealed that the 2009 H1N1 vaccine safety profile is similar to that for current seasonal influenza vaccine, with an excess risk of 0.874 cases per million vaccinations (41). There is no increase in the incidence of Guillain-Barré syndrome following 2022 to 2023 influenza vaccines among adults 65 years and older (41).
No specific methods of prevention are known.
In any case of acute weakness/paralysis, it is necessary to distinguish acute inflammatory demyelinating polyradiculoneuropathy from acute myelopathy (either transverse myelitis or acute spinal cord compression). Hyporeflexia or areflexia can be seen in both disorders at the onset, but the presence of bowel or bladder dysfunction early on or the finding of a sensory level should alert one to the prospect of acute myelopathy. Acute myelitis due to an infection caused by enteroviruses (eg, poliovirus, Coxsackievirus, etc.), West Nile virus, or another virus can produce a pure motor syndrome. However, there is usually an associated CSF pleocytosis. It is also important to exclude myasthenic crisis or acute botulism. A history of fatigability or fluctuating ocular symptoms favors the diagnosis of myasthenia. The presence of dilated unreactive pupils and severe constipation and the appearance of symptoms within 12 to 36 hours of ingestion of tainted food suggest botulism. With infections affecting nerve roots such as Lyme disease, HIV should be considered, especially when a patient presents with facial palsy or facial diplegia. Other differential diagnoses include tick paralysis, porphyric neuropathy, meningeal carcinomatosis, vasculitic neuropathy, paraneoplastic neuropathy, polymyositis, acute steroid myopathy, and, rarely, heavy metal intoxication, hypophosphatemia, and organophosphate poisoning. In patients in intensive care units, an axonal polyneuropathy occurring on a background of sepsis and multiple organ failure has been recognized as an entity distinct from Guillain-Barré syndrome.
Aside from infections, other events reported to be associated with acute inflammatory demyelinating polyradiculoneuropathy include surgery, epidural anesthesia, thrombolytic agents, heroin use, and biological drugs affecting the immune system such as anti-tumor necrosis factor alpha agents and immune checkpoint inhibitors. The incidence was higher in patients receiving CTLA-4 inhibitors than PD-1/PD-L1 inhibitors, and the risk was even higher when patients received combination therapies (08). The recommended treatment, besides to stop the immune checkpoint inhibitors, is to add prednisone to the standard treatment of intravenous immunoglobulins (see management below) (25).
Support for the clinical diagnosis of acute inflammatory demyelinating polyradiculoneuropathy may be provided by laboratory and electrodiagnostic data. The CSF is acellular in all but 10% of patients, who may have 11 to 50 cells/mm3. About 1 week after the onset of symptoms, the protein levels rise, reaching a peak in 3 to 4 weeks. Pleocytosis may signify Lyme disease, sarcoid, neoplasia, Guillain-Barré syndrome associated with HIV, Epstein-Barr virus, or other diseases. Electrophysiologic studies reveal a predominance of demyelinating features such as multifocal conduction block, slowing of nerve conduction velocities with prolonged distal and F-wave latencies, and various degrees of denervation (36).
Conduction studies are frequently normal early. Criteria for conduction block with or without temporal dispersion as well as other parameters for demyelination have been reviewed by other investigators (02). Sural sparing pattern is often seen in Guillain-Barré syndrome (06). Ancillary electrophysiologic studies include blink reflexes and assessment of autonomic function with sympathetic skin response and heart rate variability. In axonal forms of Guillain-Barré syndrome, a severe reduction in CMAP amplitudes with minimal demyelinating features is detected, with or without abnormalities in sensory nerves. In Miller-Fisher syndrome, slowing of conduction velocities in the limbs may be absent, but F-wave latencies and blink response latencies are usually abnormal, and decreased amplitudes of sensory responses may be observed. MRI and ultrasound should only be considered in selected cases with atypical presentation or to exclude mimics (45).
Corticosteroids were used to treat patients with Guillain-Barré syndrome for many years, but randomized controlled trials revealed no benefit from such treatment. On the other hand, three controlled trials that included 500 patients have established that plasmapheresis is beneficial in acute inflammatory polyradiculoneuropathy (09). When compared to untreated controls, time spent in the hospital, time on a respirator, and time to resumed ambulation are shortened in patients treated with plasmapheresis. Studies suggest that at least two sessions of plasmapheresis are required for mild cases and four sessions for the severe cases (10; 50).
A favorable response to intravenous immunoglobulin has been described in controlled trials, which showed no difference in treatment efficacy when compared to plasmapheresis (44; 34). Treatment-related fluctuations can occur with intravenous immunoglobulin or plasma exchange early in the disease course (within 8 weeks of onset) and usually respond to additional treatment with intravenous immunoglobulin or plasma exchange (37). The obvious advantages of intravenous immunoglobulin are the ease of administration and its relative safety. Intravenous immunoglobulin should be the first choice of treatment in pediatric cases in which plasmapheresis may be impractical or in patients with cardiovascular instability.
Prevention of complications, such as respiratory failure and vascular collapse, remains the cornerstone of management. In patients with rapid disease progression or bulbar dysfunction, forced vital capacity and respiratory muscle strength should be monitored closely. Up to 22% of patients require mechanical ventilation within first week of admission (47). Nasogastric tube feeding or gastrostomy may be required in patients with significant dysphagia. The prevention of nosocomial infection is important because 25% acquire pneumonias and 30% acquire urinary tract infections. Once the illness reaches the plateau phase, a systematic rehabilitation program starting with active resistive strengthening exercise should be instituted.
The most appropriate approach to patients who do not improve or progress after intravenous immunoglobulins or plasma exchange or who present with treatment-related fluctuations is presently unclear. In a randomized, double blind, placebo controlled trial, no benefit was observed from a second course of intravenous immunoglobulin in patients with poor prognosis as defined by the modified Erasmus GBS Outcome Score at days 7 to 9 (46). Similarly, the effect of a second cycle of therapy after a treatment-related fluctuation, a common clinical practice, has not been determined in randomized trials. Potential treatment on the horizon in Guillain-Barré syndrome consists of targeting the inhibition of complement cascade. The efficacy and safety of eculizumab, a humanized monoclonal antibody directed against complement component 5, was investigated in two multicenter, placebo-controlled, double-blind phase 2 trials where patients received 4 weeks of intravenous immunoglobulin plus either eculizumab or placebo. In both studies, the interpretation of efficacy was limited by small sample size (05; 30). Eculizumab appears to be well-tolerated and safe when administered in conjunction with IVIg, though anaphylaxis was observed in one patient and intracranial hemorrhage and abscess in another patient in the study (30). These findings do not preclude larger controlled trials on eculizumab in Guillain-Barré syndrome in the future. Another therapeutic strategy consists of biologicals targeting neonatal Fc receptor (FcRn) to inhibit recycling of endogenous IgG resulting in decreased IgG levels, which are now approved for treatment of myasthenia. There is a phase 2 single site trial on the safety and efficacy of efgartigimod in patients with Guillain-Barré syndrome, but it won’t be completed until May 2027.
In the short term, the risk factors for respiratory failure should be assessed early in the course of illness. These include rapid progression of limb weakness during hospital admission, Guillain-Barré syndrome disability grade 4 (unable to walk 10 m even with aid), neck flexion, facial or bulbar weakness, the inability to cough, and autonomic instability such as fluctuations in blood pressure or heart rate. A reduction in FVC greater than 30% in 24 hours likely indicates immediate transfer to ICU, whereas a 50% decline FVC in under 24 hours likely indicates the need for ventilation (45).
The main outcome parameter used in clinical trials is the ability to walk unaided after 6 months. Predictors for poor outcome (inability to walk unaided after 6 months) include advanced age, history of diarrhea, severe limb weakness with higher disability score at 2 weeks or admission, decreased CMAP amplitude (< 20% of lower limit of normal), and/or inexcitable nerves (07; 45). A notable exception to the prognostic value of early axonal involvement is with acute motor axonal neuropathy where there is often good recovery.
Studies revealed that CSF tau and serum neurofilament light chain might serve as biomarkers for axonal damage, with high levels predicting a poor outcome (01; 28). There is some evidence that CSF levels of interleukin-8, a proinflammatory chemotactic cytokine, correlates with impairment in the acute phase of Guillain-Barré syndrome and with outcome at 6 months (21).
There have been at least 35 reported cases of acute inflammatory demyelinating polyradiculoneuropathy during pregnancy. Patients respond to plasmapheresis, but there are no controlled studies assessing the safety of plasmapheresis in pregnant women with acute inflammatory demyelinating polyradiculoneuropathy (04).
Patients with acute inflammatory demyelinating polyradiculoneuropathy are sensitive to succinylcholine, muscle relaxants, and local anesthetics. Epidural or spinal anesthesia has been used with caution in these patients (03).
All contributors' financial relationships have been reviewed and mitigated to ensure that this and every other article is free from commercial bias.
Betty Soliven MD
Dr. Soliven of the University of Chicago has no relevant financial relationships to disclose.
See ProfileFrancesc Graus MD PhD
Dr. Graus, Emeritus Professor, Laboratory Clinical and Experimental Neuroimmunology, Institut D’Investigacions Biomédiques August Pi I Sunyer, Hospital Clinic, Spain, has no relevant financial relationships to disclose.
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