Electrophysiological classification of Guillain-Barré syndrome: clinical associations and outcome. Plasma Exchange/Sandoglobulin Guillain-Barré Syndrome Trial Group

Clinical features in Guillain-Barré syndrome with anti-Gal-C antibody

INTRODUCTION

Guillain-Barré syndrome (GBS) has often been associated with antibodies to glycolipids, such as galactocerebroside (Gal-C), a component of myelin. Whether patients who have GBS with anti-Gal-C antibody (Gal-C-GBS) more often have demyelinating neuropathy or axonal neuropathy remains controversial. Their clinical features have also been unestablished.

METHODS

We enrolled 47 patients with Gal-C-GBS. Their clinical and electrophysiological data were retrospectively reviewed and compared to 119 patients with GBS without anti-Gal-C antibody (non-Gal-C-GBS).

RESULTS

Demyelinating polyneuropathy occurred 4 times more frequently than axonal polyneuropathy in patients with Gal-C-GBS, but without statistical significance compared to patients with non-Gal-C-GBS (2.2:1). Patients with Gal-C-GBS had more frequent sensory deficits, autonomic involvements, and antecedent Mycoplasma pneumoniae (MP) infection than patients with non-Gal-C-GBS.

CONCLUSIONS

This is the largest study clarifying the clinical and electrophysiological findings that more frequent sensory deficits, autonomic involvements, and antecedent MP infection are associated with Gal-C-GBS.

Diagnosis of Guillain-Barré syndrome and validation of Brighton criteria

Guillain-Barré syndrome is an acute polyradiculoneuropathy with a variable clinical presentation. Accurate diagnostic criteria are essential for patient care and research, including clinical trials and vaccine safety studies. Several diagnostic criteria for Guillain-Barré syndrome have been proposed, including the recent set by the Brighton Collaboration. In the present study we describe in detail the key diagnostic features required to meet these Brighton criteria in a study population of 494 adult patients with Guillain-Barré syndrome, previously included in therapeutic and observational studies. The patients had a median age of 53 years (interquartile range 36-66 years) and males slightly predominated (56%). All patients developed bilateral limb weakness which generally involved both upper and lower extremities. The weakness remained restricted to the legs in 6% and to the arms in 1% of the patients. Decreased reflexes in paretic arms or legs were found initially in 91% of patients and in all patients during follow-up. Ten (2%) patients however showed persistence of normal reflexes in paretic arms. Disease nadir was reached within 2 weeks in 80%, within 4 weeks in 97% and within 6 weeks in all patients. A monophasic disease course occurred in 95% of patients, of whom 10% had a treatment-related fluctuation. A clinical deterioration after 8 weeks of onset of weakness occurred in 23 (5%) patients. Cerebrospinal fluid was examined in 474 (96%) patients. A mild pleocytosis (5 to 50 cells/μl) was found in 15%, and none had more than 50 cells/μl. An increased cerebrospinal fluid protein concentration was found only in 64% of patients, highly dependent on the timing of the lumbar puncture after onset of weakness (49% at the first day to 88% after 2 weeks). Nerve electrophysiology was compatible with the presence of a neuropathy in 99% of patients, but only 59% fulfilled the current criteria for a distinct subtype of Guillain-Barré syndrome. Patients with a complete data set (335) were classified according to the Brighton criteria, ranging from a high to a low level of diagnostic certainty, as level 1 in 61%, level 2 in 33%, level 3 in none, and level 4 in 6% of patients. Patients categorized in these levels did not differ with respect to proportion of patients with preceding events, initial clinical manifestations or outcome. The observed variability in the key diagnostic features of Guillain-Barré syndrome in the current cohort study, can be used to improve the sensitivity of the diagnostic criteria.

Recent developments and future directions in Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) encompasses a spectrum of acquired neuropathic conditions characterized by inflammatory demyelinating or axonal peripheral neuropathy with acute onset. Clinical and experimental studies in the past years have led to substantial progress in epidemiology, pathogenesis of GBS variants, and identification of prognostic factors relevant to treatment. In this review we provide an overview and critical assessment of the most recent developments and future directions in GBS research.

Guillain-Barré syndrome: natural history and prognostic factors: a retrospective review of 106 cases

Background

Guillain-Barre syndrome (GBS) is characterized by acute onset and progressive course, and is usually associated with a good prognosis. However, there are forms of poor prognosis, needing ventilatory support and major deficits at discharge. With this study we try to identify the factors associated with a worse outcome.

Methods

106 cases of GBS admitted in our hospital between years 2000–2010 were reviewed. Epidemiological, clinical, therapeutical and evolutionary data were collected.

Results

At admission 45% had severe deficits, percentage which improves throughout the evolution of the illness, with full recovery or minor deficits in the 87% of patients at the first year review. Ages greater than 55 years, severity at admission (p < 0.001), injured cranial nerves (p = 0.008) and the needing of ventilator support (p = 0.003) were associated with greater sequels at the discharge and at the posterior reviews in the following months. 17% required mechanical ventilation (MV). Values < 250 L/min in the Peak Flow-test are associated with an increased likelihood of requiring MV (p < 0.001).

Conclusions

Older age, severe deficits at onset, injured cranial nerves, requiring MV, and axonal lesion patterns in the NCS were demonstrated as poor prognostic factors. Peak Flow-test is a useful predictive factor of respiratory failure by its easy management.

Guillain-Barré syndrome and variants

Guillain-Barré syndrome (GBS) is characterized by rapidly evolving ascending weakness, mild sensory loss, and hyporeflexia or areflexia. Acute inflammatory demyelinating polyneuropathy was the first to be recognized over a century ago and is the most common form of GBS. Axonal motor and sensorimotor variants have been described in the last three decades and are mediated by molecular mimicry targeting peripheral nerve motor axons. Other rare phenotypic variants have been recently described with pure sensory variant, restricted autonomic manifestations, and the pharyngeal-cervical-brachial pattern. It is important to recognize GBS and its variants because of the availability of equally effective therapies in the form of plasmapheresis and intravenous immunoglobulins.

Diagnosis, treatment and prognosis of Guillain-Barré syndrome (GBS)

Guillain-Barré syndrome (GBS) is an acute polyneuropathy with a variable degree of weakness that reaches its maximal severity within 4 weeks. The disease is mostly preceded by an infection and generally runs a monophasic course. Both intravenous immunoglobulin (IVIg) and plasma exchange (PE) are effective in GBS. Rather surprisingly, steroids alone are ineffective. Mainly for practical reasons, IVIg usually is the preferred treatment. GBS can be subdivided in the acute inflammatory demyelinating polyneuropathy (AIDP), the most frequent form in the western world; acute motor axonal neuropathy (AMAN), most frequent in Asia and Japan; and in Miller-Fisher syndrome (MFS). Additionally, overlap syndromes exist (GBS-MFS overlap). About 10% of GBS patients have a secondary deterioration within the first 8 weeks after start of IVIg. Such a treatment-related fluctuation (TRF) requires repeated IVIg treatment. About 5% of patients initially diagnosed with GBS turn out to have chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) with acute onset (A-CIDP). It is yet unknown whether GBS patients who remain able to walk ('mildly affected GBS patients'), or patients with MFS, also benefit from IVIg. Despite current treatment, GBS remains a severe disease, as about 25% of patients require artificial ventilation during a period of days to months, about 20% of patients are still unable to walk after 6 months and 3-10% of patients die. Additionally, many patients have pain, fatigue or other residual complaints that may persist for months or years. Pain can also be very confusing in making the diagnosis, especially when it precedes the onset of weakness. Advances in prognostic modelling resulted in the development of a simple prognostic scale that predicts the chance for artificial ventilation, already at admission; and in an outcome scale that can be used to determine the chance to be able to walk unaided after 1, 3 or 6 months. GBS patients with a poor prognosis potentially might benefit from a more intensified treatment. A larger increase in serum IgG levels after standard IVIg treatment (0.4 g/kg/day for 5 consecutive days) seems to be related with an improved outcome after GBS. This was one of the reasons to start the second course IVIg trial (SID-GBS trial) in GBS patients with a poor prognosis. This study is currently going on. The international GBS outcome study (IGOS) is a new worldwide prognostic study that aims to get further insight in the (immune)pathophysiology and outcome of GBS, both in children and adults. Hopefully these and other studies will further help to improve the understanding and especially the outcome in patients with GBS.

The demyelination neurophysiological criteria can be misleading in Campylobacter jejuni-related Guillain-Barré syndrome

OBJECTIVE

The exclusive association of Campylobacter jejuni infection with the axonal variant of Guillain-Barré syndrome (GBS) is debatable. The current study aims to elucidate the GBS subtypes of patients with an antecedent C. jejuni infection.

METHODS

Nerve conduction study results of 73 patients with GBS were reviewed. Patients were defined as having a recent C. jejuni infection when there was a positive stool culture or serological evidence of C. jejuni in the presence of preceding diarrhea.

RESULTS

A total of 23 patients had evidence of a recent C. jejuni infection. At the early stage, patients were classified as AMAN (n=9; 39%), AIDP (n=3; 13%) or equivocal (n=9) using existing electrophysiological criteria. Prolonged distal latencies and conduction slowing that were seen in 11 patients rapidly normalized within 3 weeks in seven, whereas four had minor abnormalities throughout the course. Subsequently, all patients showed either acute motor axonal neuropathy pattern or reversible conduction failure.

CONCLUSION

Serial neurophysiology suggests that C. jejuni infections are exclusive to axonal GBS.

SIGNIFICANCE

Our findings suggest that AMAN can demonstrate the full complement of demyelinating features at the early stages of disease.

Pharmacological treatment other than corticosteroids, intravenous immunoglobulin and plasma exchange for Guillain-Barré syndrome

BACKGROUND

Plasma exchange and intravenous immunoglobulin, but not corticosteroids, are beneficial in Guillain-Barré syndrome (GBS). The efficacy of other pharmacological agents is unknown. This review was first published in 2011 and this update in 2013. 

OBJECTIVES

To review systematically the evidence from randomised controlled trials (RCTs) for pharmacological agents other than plasma exchange, intravenous immunoglobulin and corticosteroids.

SEARCH METHODS

On 28 August 2012, we searched the Cochrane Neuromuscular Disease Group Specialized Register CENTRAL (2012, Issue 8 in The Cochrane Library), MEDLINE (January 1966 to August 2012) and EMBASE (January 1980 to August 2012) for treatments for GBS. We considered evidence from non-randomised studies in the Discussion.

SELECTION CRITERIA

We included all randomised or quasi-RCTs of acute (within four weeks from onset) GBS of all types, ages and degrees of severity. We discarded trials which only tested corticosteroids, intravenous immunoglobulin or plasma exchange. We included other pharmacological treatments or combinations of treatments compared with no treatment, placebo treatment or another treatment.

DATA COLLECTION AND ANALYSIS

Change in disability after four weeks was the primary outcome. Two authors checked references and extracted data independently. One author entered and another checked data in Review Manager (RevMan). We assessed risk of bias according to the Cochrane Handbook for Systematic Reviews of Interventions. We calculated mean differences and risk ratios with their 95% confidence intervals. We assessed strength of evidence with GradePro software.

MAIN RESULTS

Only very low quality evidence was found for four different interventions. This update of the review found no new trials. One RCT with 13 participants showed no significant difference in any outcome between interferon beta-1a and placebo. Another with 10 participants showed no significant difference in any outcome between brain-derived neurotrophic factor and placebo. A third with 37 participants showed no significant difference in any outcome between cerebrospinal fluid filtration and plasma exchange. In a fourth with 20 participants, the risk ratio of improving by one or more disability grades after eight weeks was significantly greater with the Chinese herbal medicine tripterygium polyglycoside than with corticosteroids (risk ratio 1.47; 95% confidence interval 1.02 to 2.11). Serious adverse events were uncommon with each of these treatments and not significantly commoner in the treated than the control groups.

AUTHORS' CONCLUSIONS

The quality of the evidence was very low. Three small RCTs, of interferon beta-1a, brain-derived neurotrophic factor and cerebrospinal fluid filtration, showed no significant benefit or harm. A fourth small trial showed that the Chinese herbal medicine tripterygium polyglycoside hastened recovery significantly more than corticosteroids but this result needs confirmation. It was not possible to draw useful conclusions from the few observational studies.

Muscle MRI in severe Guillain-Barré syndrome with motor nerve inexcitability

We report on the clinical, electrophysiological, and lower-limb musculature MRI findings in a severe demyelinating Guillain-Barré syndrome (GBS) patient with follow-up over 6 months. After 3 weeks of tetraplegia and mechanical ventilation, there was progressive improvement until almost complete recovery. On day 4 after onset, electrophysiological study revealed absent F waves and widespread conduction block. On four further electrophysiological studies on days 12, 19, 45, and 150, there was marked and reversible slow down of motor conduction velocities in upper-limb nerves, and persistent inexcitability of lower-limb nerves. Mild signs of active denervation were recorded in calf and foot muscles as of day 45. On day 39, MRI T2-weighted fat-suppressed images showed patchy hypersignal of variable intensity involving pelvic, thigh, and calf muscles, which disappeared in a second imaging study on day 190; in this study T1-weighted images did not disclose muscle fatty atrophy. We conclude that in severe demyelinating GBS prolonged motor nerve inexcitability should not necessarily be taken as a predictor of poor prognosis, and that MRI is useful in assessing the topography and evolution of muscle denervation.

Antibody testing in peripheral nerve disorders

The identification of autoantibodies associated with dysimmune neuropathies was a major contribution to the characterization of peripheral nerve disorders, the understanding of their pathophysiology, and the clinical diagnosis of neuropathies. Antibodies directed to GM1, GQ1b, and disyalilated gangliosides, and anti-MAG antibodies are very useful in the diagnosis of acute or chronic motor or sensory-motor neuropathies with or without monoclonal IgM. Anti-onconeural anti-Hu and anti-CV2/CRMP antibodies allow when they are detected the diagnosis of paraneoplastic neuropathies. This chapter focuses on the description of these antibodies as diagnostic markers and on their immunopathogenesis. We give a background overview on the origin of these antibodies, their detection, and review those studies, which clearly show that these antibodies are capable of binding to the target tissues in peripheral nerve and thereby can exert a variety of pathophysiological effects. The corresponding electrophysiological and histological changes observed both in human and animal models are exemplified in order to get a better understanding of the immune mechanisms of these antibody-mediated neuropathies.

Peripheral neuropathy in the elderly

Peripheral neuropathy is an important factor of disability in the elderly, which is significant now that up to 20% of the population is older than 60 years in industrialized countries. Potentially treatable neuropathies including primary inflammatory polyneuropathies and systemic disorders, especially vasculitic neuropathies, are as common in this age group as in younger patients. Neuropathies associated with diabetes, malignancy, and monoclonal gammopathies are even more common in these patients. It is thus essential to identify the causes of these neuropathies in this group of patients and treat them whenever feasible.

The Guillain-Barré syndrome

The latest estimation for the frequency of Guillain-Barré syndrome (GBS) is 1.1 to 1.8 per 100000 persons per year. Guillain-Barré syndrome is today divided into two major subtypes: acute inflammatory demyelinating polyneuropathy (AIDP) and the axonal subtypes, acute motor axonal neuropathy (AMAN) and acute motor and sensory axonal neuropathy (AMSAN). The axonal forms of GBS are caused by certain autoimmune mechanisms, due to a molecular mimicry between antecedent bacterial infection (particularly Campylobacter jejuni) and human peripheral nerve gangliosides. Improvements in patient management in intensive care units has permitted a dramatic drop in mortality rates. Immunotherapy, including plasma exchange (PE) or intravenous immunoglobulin (IVIg), seems to shorten the time to recovery, but their effect remains limited. Further clinical investigations are needed to assess the effect of PE or IVIg on the GBS patients with mild affection, no response, or relapse.

Electrophysiological subtypes and prognosis of Guillain-Barré syndrome in northeastern China

INTRODUCTION

The purpose of this study was to assess the electrophysiological subtypes and prognosis of Guillain-Barré syndrome (GBS) in northeastern China.

METHODS

Ninety-nine patients with GBS were recruited between 2006 and 2010 and retrospectively reviewed.

RESULTS

Sixty-seven percent of patients had acute inflammatory demyelinating polyneuropathy (AIDP). Patients with acute motor axonal neuropathy (AMAN) had more severe symptoms at onset of GBS, and intravenous immunoglobulin (IVIg) was less effective in these patients. The prognosis may have been associated with the severity of the illness and did not differ between AMAN and AIDP patients. Abnormal motor nerve conduction studies (NCS) of the lower limbs and sensory NCS of the upper limbs with normal sural sensory nerve studies were the main electrophysiological features of AIDP.

CONCLUSIONS

AIDP is the main subtype of GBS, and it has specific electrophysiological characteristics in northeastern China. The prognosis of patients with AMAN was similar to that of patients with AIDP. Moreover, IVIg was more effective in patients with AIDP.

Risk factors of respiratory failure in children with Guillain-Barré syndrome

BACKGROUND

Respiratory failure is rarely associated with Guillain-Barré syndrome (GBS) in children. The aim of the study was to determine the risk factors of respiratory failure in children with GBS to advance management.

METHODS

In this retrospective study, the variables that lead to respiratory failure were investigated in 40 children. The risk factors were compared for 4 children with intubation and 36 without. We also analyzed the specific treatments, including corticosteroids, intravenous immunoglobulin, plasmapheresis, and clinical status at discharge.

RESULTS

Four (10.0%) of the 40 children with GBS required mechanical ventilation. The need for mechanical ventilation was significantly related to the Hughes score at nadir (p<0.001), respiratory distress (p<0.001), and hypotension (p<0.001). Atypical presentation of symptoms such as croup, hoarseness, vomiting, ataxia, consciousness disturbance, and previous event of diarrhea were more predominant in patients younger than 6 years. Disability grades >3 at discharge were found in 15 patients (37.5%), and there was no mortality in the present case series.

CONCLUSIONS

Respiratory failure in childhood GBS was related to the Hughes score at nadir, respiratory distress, and hypotension. Atypical presentations of symptoms were more predominant in patients younger than 6 years. The prognosis in our series was good and not related to previous events. Understanding the risk factors of severe GBS will provide better treatment strategies and improve the outcomes.

An antibody to the GM1/GalNAc-GD1a complex correlates with development of pure motor Guillain-Barré syndrome with reversible conduction failure

Antibodies to a ganglioside complex consisting of GM1 and GalNAc-GD1a (GM1/GalNAc-GD1a) are found in sera from patients with Guillain-Barré syndrome (GBS). To elucidate the clinical significance of anti-GM1/GalNAc-GD1a antibodies in GBS, clinical features of 58 GBS patients with IgG anti-GM1/GalNAc-GD1a antibodies confirmed by enzyme-linked immunosorbent assay and thin layer chromatography immunostaining were analyzed. Compared to GBS patients without anti-GM1/GalNAc-GD1a antibodies, anti-GM1/GalNAc-GD1a-positive patients more frequently had a preceding respiratory infection (n=38, 66%, p<0.01) and were characterized by infrequency of cranial nerve deficits (n=9, 16%, p<0.01) and sensory disturbances (n=26, 45%, p<0.01). Of the 28 anti-GM1/GalNAc-GD1a-positive patients for whom electrophysiological data were available, 14 had conduction blocks (CBs) at intermediate segments of motor nerves, which were not followed by evident remyelination. Eight of 10 bedridden cases were able to walk independently within one month after the nadir. These results show that the presence of anti-GM1/GalNAc-GD1a antibodies correlated with pure motor GBS characterized by antecedent respiratory infection, fewer cranial nerve deficits, and CBs at intermediate sites of motor nerves. The CB may be generated through alteration of the regulatory function of sodium channels in the nodal axolemma.

Diagnosis, epidemiology and treatment of inflammatory neuropathies

This article reviews the main diagnostic, epidemiological and therapeutic issues relating to the three main inflammatory neuropathies: Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy and multifocal motor neuropathy. The current knowledge base and recent developments are described.

Nodal proteins are target antigens in Guillain-Barré syndrome

Neurofascin-186 (NF186), neuronal cell adhesion molecule (NrCAM), and gliomedin are adhesion molecules playing a central role in the formation of nodes of Ranvier. In Guillain-Barré syndrome (GBS), immune attack toward the nodes may participate in the disabilities. Autoantibodies to NF186 and gliomedin have been detected in a rat model of GBS. Here, we investigated the prevalence of antibodies against nodal adhesion molecules in patients with GBS or chronic inflammatory demyelinating polyneuropathy (CIDP). Sera from 100 GBS patients, 50 CIDP patients, 80 disease controls, and 50 healthy controls were tested for their ability to bind the nodes of Ranvier. To characterize the antigens, we performed cell binding assays against NF186, gliomedin, contactin, and NrCAM. We found that 43% of patients with GBS and 30% of patients with CIDP showed IgG fixation at nodes or paranodes. In eight patients with GBS or CIDP, we identified that IgG antibodies recognized the native extracellular domain of NF186, gliomedin, or contactin. Also, 29 patients showed IgM against nodal adhesion molecules. However, we did not detect IgM fixation at nodes or paranodes. Antibodies to gliomedin or NF186 were mostly detected in demyelinating and axonal GBS, respectively. The adsorption of the antibodies to their soluble antigens abolished IgG deposition at nodes and paranodes in nerves, indicating these were specific to NF186, gliomedin, and contactin. In conclusion, gliomedin, NF186, and contactin are novel target antigens in GBS. At nodes, additional epitopes are also the targets of IgG. These results suggest that antibody attack against nodal antigens participates in the etiology of GBS.

Intravenous immunoglobulin for Guillain-Barré syndrome

BACKGROUND

Guillain-Barré syndrome (GBS) is an acute, paralysing, inflammatory peripheral nerve disease. Intravenous immunoglobulin (IVIg) is beneficial in other autoimmune diseases. This is an update of a review first published in 2001 and previously updated in 2003, 2005, 2007 and 2010. Other Cochrane systematic reviews have shown that plasma exchange (PE) significantly hastens recovery in GBS compared with supportive treatment alone, and that corticosteroids alone are ineffective.

OBJECTIVES

To determine the efficacy of IVIg for GBS.

SEARCH METHODS

We searched the Cochrane Neuromuscular Disease Group Specialized Register (15 August 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 3), MEDLINE (January 1966 to August 2011) and EMBASE (January 1980 to August 2011). We checked the bibliographies in reports of the randomised trials and contacted the authors and other experts in the field to identify additional published or unpublished data.

SELECTION CRITERIA

Randomised and quasi-randomised trials of IVIg compared with no treatment, placebo treatment, PE, or other immunomodulatory treatments in children and adults with GBS of all degrees of severity. We also included trials in which IVIg was added to another treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently selected papers, extracted data and assessed quality. We collected data about adverse events from the included trials.

MAIN RESULTS

In this review, seven trials with a variable risk of bias compared IVIg with PE in 623 severely affected participants. In five trials with 536 participants for whom the outcome was available, the mean difference (MD) of change in a seven-grade disability scale after four weeks was not significantly different between the two treatments: MD of 0.02 of a grade more improvement in the intravenous immunoglobulin than the plasma exchange group; 95% confidence interval (CI) 0.25 to -0.20. There were also no statistically significant differences in the other measures considered. Three studies including a total of 75 children suggested that IVIg significantly hastens recovery compared with supportive care.In one trial involving 249 participants comparing PE followed by IVIg with PE alone, the mean grade improvement was 0.2 (95% CI -0.14 to 0.54) more in the combined treatment group than in the PE alone group; not clinically significantly different, but not excluding the possibility of significant extra benefit. Another trial with 37 participants comparing immunoabsorption followed by IVIg with immunoabsorption alone did not reveal significant extra benefit from the combined treatment.Adverse events were not significantly more frequent with either treatment, but IVIg is significantly much more likely to be completed than PE.Small trials in children showed a trend towards more improvement with high-dose compared with low-dose IVIg, and no significant difference when the standard dose was given over two days rather than five days.

AUTHORS' CONCLUSIONS

A previous Cochrane review has shown that PE hastens recovery compared with supportive treatment alone. There are no adequate comparisons of IVIg with placebo in adults, but this review provides moderate quality evidence that, in severe disease, IVIg started within two weeks from onset hastens recovery as much as PE. Adverse events were not significantly more frequent with either treatment but IVIg is significantly much more likely to be completed than PE. Also, according to moderate quality evidence, giving IVIg after PE did not confer significant extra benefit. In children, according to low quality evidence, IVIg probably hastens recovery compared with supportive care alone. More research is needed in mild disease and in patients whose treatment starts more than two weeks after onset. Dose-ranging studies are also needed.

Electrodiagnostic criteria for Guillain-Barrè syndrome: a critical revision and the need for an update

Electrophysiology plays a determinant role in Guillain-Barré syndrome (GBS) diagnosis, classification of the subtypes and in establishing prognosis. In the last three decades, different electrodiagnostic criteria sets have been proposed for acute inflammatory demyelinating neuropathy (AIDP), acute motor axonal neuropathy (AMAN) and acute motor and sensory axonal neuropathy (AMSAN). Criteria sets for AIDP varied for the parameters indicative of demyelination considered, for the cut-off limits and the number of required abnormalities (all a priori established) showing different sensitivities. Criteria sets for AMAN and AMSAN were proposed on the initial assumption that these subtypes were pathologically characterised by simple axonal degeneration. However, some AMAN patients show transient conduction block/slowing in intermediate and distal nerve segments, mimicking demyelination but without the development of abnormal temporal dispersion, named reversible conduction failure (RCF). The lack of distinction between RCF and demyelinating conduction block leads to fallaciously classify AMAN patients with RCF as AIDP or AMAN with axonal degeneration. Serial electrophysiological studies are mandatory for proper diagnosis of GBS subtypes, identification of pathophysiological mechanisms and prognosis. More reliable electrodiagnostic criteria should be devised to distinguish axonal and demyelinating subtypes of GBS, taking into consideration the RCF pattern and focussing on temporal dispersion.

Fc receptor like 3 in Chinese patients of Han nationality with Guillain-Barré syndrome

Fc receptor like 3 gene (FcRL3) has been associated with some autoimmune diseases. Here, its role in Guillain-Barré syndrome (GBS) was evaluated by studying nine FcRL3 gene SNPs in a Chinese cohort of GBS patients. The frequencies of FcRL3-3-169C, FcRL3-6 intron3A, and FcRL3-8 exon15G alleles were significantly increased in GBS patients compared with healthy controls. The frequency of FcRL3-1→9 CCTGGAGAA haplotype was significantly increased, and the frequencies of FcRL3-1→9 CCTACAAAA,CCCACGAAA, and CCTGCGGAA haplotypes were significantly decreased compared with healthy controls. These results suggest that FcRL3 is associated with GBS incidence.

Effect of stem cell transplantation for B-cell malignancies on disease course of associated polyneuropathy

B cell dyscrasias are often refractory to medical treatments, and hematological stem cell therapy (SCT) may be warranted. It is not clear whether an associated polyneuropathy may also profit from SCT. In exceptional cases SCT has been tried in patients with monoclonal gammopathy and progressive polyneuropathy refractory to medical treatments. In a cohort of 225 patients with monoclonal gammopathy and polyneuropathy, we selected the six patients who underwent SCT and retrospectively examined the effects of SCT on the disease course of the associated polyneuropathy. In all patients except one, the indication for SCT was hemato-oncological (multiple myeloma in 4 patients and primary AL amyloidosis in 1). The remaining patient had an IgG monoclonal gammopathy of undetermined significance and a progressive and painful polyneuropathy for which she was treated with SCT. SCT led to improvement of motor scores and autonomic symptoms in one patient; three patients experienced improvement of neuropathic pain or sensory deficits but showed further progression of weakness. One patient showed no improvement at all. One patient died within 100 days after SCT. In conclusion, SCT as a treatment of refractory hematological malignancy may occasionally have a positive effect on the associated progressive polyneuropathy, although the benefits are very limited and the treatment-related mortality is high.

Relevance of anxiety in clinical practice of Guillain-Barre syndrome: a cohort study

OBJECTIVES

Illness is often associated with anxiety, but few data exist about the prognostic significance of this phenomenon. To address this issue, we assessed whether patient anxiety is associated with subsequent need for intubation in Guillain-Barré syndrome (GBS).

DESIGN

Incident case-cohort study.

SETTING

Acute secondary care in a teaching hospital (France) from 2006 to 2010.

PARTICIPANTS

110 adult GBS patients. Either language barrier or cognitive decline that precluded understanding was considered as exclusion criteria.

PRIMARY OUTCOME

Acute respiratory failure.

INTERVENTIONS

At admission, anxiety and clinical factors (including known predictors of respiratory failure: delay between GBS onset and admission, inability to lift head, vital capacity (VC)) were assessed and related to subsequent need for mechanical ventilation (MV). Anxiety was assessed using a Visual Analogical Scale (VAS), the State Anxiety Inventory form Y1 (STAI-Y1) score and a novel-specific questionnaire, evaluating fears potentially triggered by GBS. Patients were asked to choose which they found most stressful from weakness, pain, breathlessness and uncertainty.

RESULTS

23 (22%) were subsequently ventilated. Mean STAI-Y1 was 47.2 (range 22-77) and anxiety VAS 5.2 (range 0-10). STAI was above 60/80 in 22 (21%) patients and anxiety VAS above 7/10 in 28 (27%) patients. Fear of remaining paralysed, uncertainty as to how the disease would progress and fear of intubation were the most stressful. Factors significantly associated with anxiety were weakness and bulbar dysfunction. STAI-Y1 was higher and uncertainty more frequent in subsequently ventilated patients, who had shorter onset-admission delay and greater weakness but not a lower VC. Uncertainty was independently associated with subsequent MV.

CONCLUSIONS

Early management of patients with GBS should evaluate anxiety and assess its causes both to adjust psychological support and to anticipate subsequent deterioration.

Guillain-Barré syndrome associated with normal or exaggerated tendon reflexes

Areflexia is part one of the clinical criteria required to make a diagnosis of Guillain-Barré syndrome (GBS). The diagnostic criteria were stringently developed to exclude non-GBS cases but there have been reports of patients with GBS following Campylobacter jejuni enteritis with normal and exaggerated deep tendon reflexes (DTRs). The aim of this study is to expand the existing diagnostic criteria to preserved DTRs. From the cohort of patients referred for anti-ganglioside antibody testing from hospitals throughout Japan, 48 GBS patients presented with preserved DTR at admission. Thirty-two patients had normal or exaggerated DTR throughout the course of illness whereas in 16 patients the DTR became absent or diminished during the course of the illness. IgG antibodies against GM1, GM1b, GD1a, or GalNAc-GD1a were frequently present in either group (84 vs. 94%), suggesting a close relationship between the two groups. We then investigated the clinical and laboratory findings of 213 GBS patients from three hospital cohorts. In 23 patients, eight presented with normal tendon reflexes throughout the clinical course of the illness. Twelve showed hyperreflexia, with at least one of the jerks experienced even at nadir, and exaggerated reflexes returning to normal at recovery. The other three had hyperreflexia throughout the disease course. Compared to 190 GBS patients with reduced or absent DTR, the 23 DTR-preserved patients more frequently presented with pure motor limb weakness (87 vs. 47%, p = 0.00026), could walk 5 m independently at the nadir (70 vs. 33%, p = 0.0012), more frequently had antibodies against GM1, GM1b, GD1a, or GalNAc-GD1a (74 vs. 47%, p = 0.014) and were more commonly diagnosed with acute motor axonal neuropathy (65 vs. 34%, p = 0.0075) than with acute inflammatory demyelinating polyneuropathy (13 vs. 43%, p = 0.0011). This study demonstrated that DTRs could be normal or hyperexcitable during the entire clinical course in approximately 10% of GBS patients. This possibility should be added in the diagnostic criteria for GBS to avoid delays in diagnosis and effective treatment to these patients.

Guillain-barre syndrome following spinal fusion for thoracic vertebral fracture

There have been very few reports in the literature of Guillain-Barré syndrome (GBS) after spinal surgery. We present a unique case of GBS following spinal fusion for thoracic vertebral fracture. The aim of this report is to illustrate the importance of early neurological assessment and determining the exact cause of a new neurological deficit that occurs after an operation.

Fibrinogen is not elevated in the cerebrospinal fluid of patients with multiple sclerosis

Background

Elevated plasma fibrinogen levels are a well known finding in acute infectious diseases, acute stroke and myocardial infarction. However its role in the cerebrospinal fluid (CSF) of acute and chronic central (CNS) and peripheral nervous system (PNS) diseases is unclear.

Findings

We analyzed CSF and plasma fibrinogen levels together with routine parameters in patients with multiple sclerosis (MS), acute inflammatory diseases of the CNS (bacterial and viral meningoencephalitis, BM and VM) and PNS (Guillain-Barré syndrome; GBS), as well as in non-inflammatory neurological controls (OND) in a total of 103 patients. Additionally, MS patients underwent cerebral MRI scans at time of lumbar puncture.

CSF and plasma fibrinogen levels were significantly lower in patients with MS and OND patients as compared to patients with BM, VM and GBS. There was a close correlation between fibrinogen levels and albumin quotient (rho = 0.769, p < 0.001) which strongly suggests passive transfer of fibrinogen through the blood-CSF-barrier during acute inflammation. Hence, in MS, the prototype of chronic neuroinflammation, CSF fibrinogen levels were not elevated and could not be correlated to clinical and neuroradiological outcome parameters.

Conclusions

Although previous work has shown clear evidence of the involvement of fibrinogen in MS pathogenesis, this is not accompanied by increased fibrinogen in the CSF compartment.

Guillain-Barré Syndrome in India: population-based validation of the Brighton criteria

OBJECTIVE

Case definitions of GBS were recently developed in response to the 2009 H1N1 vaccination programme but have undergone limited field testing. We validate the sensitivity of the Brighton Working Group case definitions for Guillain-Barré Syndrome (GBS) using a population-based cohort in India.

METHODS

The National Polio Surveillance Unit of India actively collects all cases of acute flaccid paralysis (AFP) in children <15 years old, including cases of GBS. Cases of GBS with available cerebrospinal fluid (CSF) and nerve conduction studies (NCS) results, neurological examination, clinical history, and exclusion of related diagnoses were selected (2002-2003). Relevant data were abstracted and entered into a central database. Sensitivity of the Brighton GBS criteria for level 3 of diagnostic certainty which requires no clinical laboratory testing, level 2 which employs CSF or NCS, and level 1 which employs both, were calculated.

RESULTS

79 cases of GBS (mean age 6.5 years, range 4.0-14.5; 39% female) met the case definition. GBS cases were ascending (79%), symmetrical (85%), and bilateral (100%); involving lower extremity hypotonia (86%) and weakness (100%), upper extremity hypotonia (62%) and weakness (80%), areflexia/hyporeflexia (88%), respiratory muscles (22%), bulbar muscles (22%), and cranial nerves (13%). Four limbs were involved in 80% of cases. Mean time to maximal weakness was 5.2 days (range 0.5-30 days) with nadir GBS disability scores of 3 (7%), 4 (67%), 5 (15%), 6 (10%), or unclear (1%). CSF (mean time to lumbar puncture 29 days) was normal in 29% with cytoalbuminologic dissociation in 65% (mean protein 105 mg/dL, range 10-1000; mean cell count 11/μL, range 0-220, n=4 with >50 cells/μL). Significant improvement occurred in 73% whereas death (9%) occurred 6-29 days after sensorimotor symptom onset. The majority of cases (86%) fulfilled Brighton level 3, level 2 (84%), and level 1 (62%) of diagnostic certainty.

CONCLUSION

The diagnosis of GBS can be made using Brighton Working Group criteria in India with moderate to high sensitivity. Brighton Working Group case definitions are a plausible standard for capturing a majority of cases of GBS in field operations in low income settings during AFP surveillance.

Campylobacter jejuni DNA-binding protein from starved cells in Guillain-Barré syndrome patients

Campylobacter jejuni enteritis is frequently associated with an axonal form of Guillain-Barré syndrome (GBS) and C. jejuni DNA-binding protein from starved cells (C-Dps) induces paranodal myelin detachment and axonal degeneration through binding with sulfatide in vivo. Here we investigated the invasion of C-Dps into hosts with C. jejuni-related GBS. Our analyses of patient sera found that both C-Dps and anti-C-Dps antibodies were most commonly detected in sera from C. jejuni-related GBS patients (5/27, 14.8% and 15/24, 62.5%; respectively). These findings suggest that C-Dps invades the host and may potentially contribute to the peripheral nerve damage in C. jejuni-related GBS.

Acute lung failure

Lung failure is the most common organ failure seen in the intensive care unit. The pathogenesis of acute respiratory failure (ARF) can be classified as (1) neuromuscular in origin, (2) secondary to acute and chronic obstructive airway diseases, (3) alveolar processes such as cardiogenic and noncardiogenic pulmonary edema and pneumonia, and (4) vascular diseases such as acute or chronic pulmonary embolism. This article reviews the more common causes of ARF from each group, including the pathological mechanisms and the principles of critical care management, focusing on the supportive, specific, and adjunctive therapies for each condition.

Pain in Guillain-Barré syndrome

Evaluation of: Ruts L, Drenthen J, Jongen JL et al. Pain in Guillain-Barré syndrome: a long-term follow-up study. Neurology 75, 1439-1447 (2010). Pain has been recognized as an important symptom of Guillain-Barré syndrome (GBS). The article under review prospectively studied the phenomenon of pain in a cohort of 156 GBS patients for a period of 1 year. It confirmed that pain of significant intensity is relatively common in all subtypes of GBS. It may start before the onset of other symptoms. It correlates with sensory loss, severity of the GBS at its nadir and the presence of diarrhea. In the recovery/chronic stages it correlates with weakness, disability and fatigue. Up to a third of patients have pain at 1 year.

Purple pigments: the pathophysiology of acute porphyric neuropathy

The porphyrias are inherited metabolic disorders arising from disturbance in the haem biosynthesis pathway. The neuropathy associated with acute intermittent porphyria (AIP) occurs due to mutation involving the enzyme porphobilinogen deaminase (PBGD) and is characterised by motor-predominant features. Definitive diagnosis often encompasses a combination of biochemical, enzyme analysis and genetic testing, with clinical neurophysiological findings of a predominantly motor axonal neuropathy. Symptomatic and supportive treatment are the mainstays during an acute attack. If administered early, intravenous haemin may prevent progression of neuropathy. While the pathophysiology of AIP neuropathy remains unclear, axonal dysfunction appears intrinsically linked to the effects of neural energy deficits acquired through haem deficiency coupled to the neurotoxic effects of porphyrin precursors. The present review will provide an overview of AIP neuropathy, including discussion of recent advances in understanding developed through neurophysiological approaches that have further delineated the pathophysiology of axonal degeneration.

Locked-in syndrome in three children with Guillain-Barré syndrome

Locked-in syndrome is a rare disorder in childhood. It resembles brain death, but patients are fully conscious, and incapable of communicating because of the complete paralysis of voluntary muscles. Although it can be caused by Guillain-Barré syndrome, it is rarely reported in pediatrics. We describe three pediatric cases of locked-in syndrome in patients with Guillain-Barré syndrome presenting acute tetraplegia, areflexia, cranial nerve involvement, and albuminocytologic dissociation in the cerebrospinal fluid. Electrophysiologic studies indicated acute motor axonal polyradiculoneuropathy in one patient, and acute motor sensory axonal polyradiculoneuropathy in the other two. Most Guillain-Barré syndrome patients with locked-in syndrome demonstrate nerve inexcitability in neurophysiologic studies, poor clinical outcomes, and increased risk of sequelae.

Impact of medical audit on electrodiagnostic medicine in polyneuropathy

OBJECTIVE

The aim of the study was to investigate whether experienced physicians' electrodiagnostic practice and criteria can be influenced by international collaboration involving peer review medical audit.

METHODS

Data was obtained from the ESTEEM project, an ongoing collaboration since 1991 among European neurophysiologists concerned with quality improvement in electrodiagnostic medicine. Three sets of the physicians' polyneuropathy examinations performed with intervals of 2-4 years were analysed.

RESULTS

Changes towards increased homogeneity among the physicians were found in (1) the average number of studies performed per patient and the number of abnormal studies required for accepting the diagnosis of polyneuropathy, with the most pronounced changes seen for abnormal motor nerve segments, abnormal F-wave studies, and electromyographic studies, and (2) the agreement on pathophysiological interpretation of nerve conduction studies and classification of polyneuropathy.

CONCLUSIONS

Changes towards increased homogeneity contributed to years of participation in peer review medical audit, were seen among a group of experienced physicians. Peer review medical audit as carried out here is however difficult to scale up. Therefore guidelines or minimal criteria should ideally supplement a medical audit process to disseminate the results obtained to a larger audience.

SIGNIFICANCE

These results support the role of international peer review medical audit in quality improvement of electrodiagnostic medicine.