How often and when Fisher syndrome is overlapped by Guillain-Barré syndrome or Bickerstaff brainstem encephalitis?

Current status of Guillain-Barré syndrome (GBS) in China: a 10-year comprehensive overview

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy; a disease involving the peripheral nervous system which is the most common cause of acute flaccid paralysis worldwide. So far, it is still lack of a comprehensive overview and understanding of the national epidemiological, clinical characteristics, and the risk factors of GBS in China, as well as differences between China and other countries and regions in these respects. With the global outbreak of the coronavirus disease 2019 (COVID-19), an epidemiological or phenotypic association between severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and GBS has attracted great attention. In this review, we outlined the current clinical data of GBS in China by retrieving literature, extracting and synthesizing the data of GBS in China from 2010 to 2021. Besides, we compared the characteristics of epidemiology, preceding events and clinical profiles of GBS between China and other countries and regions. Furthermore, in addition to conventional intravenous immunoglobulin (IVIG) and plasma exchange (PE) therapy, the potential therapeutic effects with novel medications in GBS, such as complement inhibitors, etc., have become the research focus in treatments. We found that epidemiological and clinical findings of GBS in China are approximately consistent with those in the International GBS Outcome Study (IGOS) cohort. We provided an overall picture of the present clinical status of GBS in China and summarized the global research progress of GBS, aiming to further understand the characteristics of GBS and improve the future work of GBS worldwide, especially in countries with the middle and low incomes.

Clinical characteristics and prognosis of temporary miller fisher syndrome following COVID-19 vaccination: a systematic review of case studies

BACKGROUND

Miller Fisher syndrome (MFS) is a subtype of Guillain-Barré syndrome (GBS) which is characterized by the three components of ophthalmoplegia, ataxia, and areflexia. Some studies reported MFS as an adverse effect of the COVID-19 vaccination. We aimed to have a detailed evaluation on demographic, clinical, and para-clinical characteristics of subjects with MFS after receiving COVID-19 vaccines.

MATERIALS AND METHODS

A thorough search strategy was designed, and PubMed, Web of Science, and Embase were searched to find relevant articles. Each screening step was done by twice, and in case of disagreement, another author was consulted. Data on different characteristics of the patients and types of the vaccines were extracted. The risk of bias of the studies was assessed using Joanna Briggs Institute (JBI) tools.

RESULTS

In this study, 15 patients were identified from 15 case studies. The median age of the patients was 64, ranging from 24 to 84 years. Ten patients (66.6%) were men and Pfizer made up 46.7% of the injected vaccines. The median time from vaccination to symptoms onset was 14 days and varied from 7 to 35 days. Furthermore,14 patients had ocular signs, and 78.3% (11/14) of ocular manifestations were bilateral. Among neurological conditions, other than MFS triad, facial weakness or facial nerve palsy was the most frequently reported side effect that was in seven (46.7%) subjects. Intravenous immunoglobulin (IVIg) was the most frequently used treatment (13/15, 86.7%). Six patients received 0.4 g/kg and the four had 2 g/kg. Patients stayed at the hospital from five to 51 days. No fatal outcomes were reported. Finally, 40.0% (4/15) of patients completely recovered, and the rest experienced improvement.

CONCLUSION

MFS after COVID-19 immunization has favorable outcomes and good prognosis. However, long interval from disease presentation to treatment in some studies indicates that more attention should be paid to MFS as the adverse effect of the vaccination. Due to the challenging diagnosis, MFS must be considered in list of the differential diagnosis in patients with a history of recent COVID-19 vaccination and any of the ocular complaints, ataxia, or loss of reflexes, specially for male patients in their 60s and 70s.

Miller-Fisher syndrome with positive anti-GD1b and anti-GM1 antibodies combined with multiple autoimmune antibodies: A case report

RATIONALE

Anti-ganglioside antibodies (AGA) play an essential role in the development of Miller-Fisher syndrome (MFS). The positive rate of ganglioside antibodies was exceptionally high in MFS, especially anti-GQ1b antibodies. However, the presence of other ganglioside antibodies does not exclude MFS.

PATIENT CONCERNS

We present a 48-year-old male patient who suddenly developed dizziness, visual rotation, nausea, and vomiting accompanied by unsteady gait and diplopia for 3 days before presentation to our clinic.

DIAGNOSES

On physical examination, the patient's right eye could not fully move to the right side and horizontal nystagmus was found. Coordination was also impaired in the upper and lower extremities with dysmetria and dysdiadochokinesia. The electromyography and cerebrospinal fluid examination results were normal. The serum anti-GQlb antibody test results were negative. However, serum anti-GD1b IgM and anti-GM1 IgM antibodies were positive. Meanwhile, the anti-thyroid peroxidase antibody was >600.00 IU/mL (0.00-34.00), and the anti-SS-A/Ro52 antibody was positive. He was diagnosed with MFS.

INTERVENTIONS

The patient received IVIg treatment for 5 days (0.4 g/kg/day) from day 2 to day 6 of hospitalization. On the 7th day of admission, the patient was administered intravenous methylprednisolone (500 mg/day), which was gradually reduced.

OUTCOMES

The patient's symptoms improved after treatment with immunoglobulins and hormones.

LESSONS

We report a case of MFS with positive anti-GD1b and anti-GM1 antibodies combined with multiple autoimmune antibodies. Positive ganglioside antibodies may be used as supporting evidence for the diagnosis; however, the diagnosis of MFS is more dependent on clinical symptoms.

Miller Fisher syndrome: an updated narrative review

Introduction

Miller Fisher syndrome (MFS) is considered a rare variant of Guillain-Barré syndrome (GBS), a group of acute-onset immune-mediated neuropathies characterized by the classic triad of ataxia, areflexia, and ophthalmoparesis. The present review aimed to provide a detailed and updated profile of all aspects of the syndrome through a collection of published articles on the subject, ranging from the initial description to recent developments related to COVID-19.

Methods

We searched PubMed, Scopus, EMBASE, and Web of Science databases and gray literature, including references from the identified studies, review studies, and conference abstracts on this topic. We used all MeSH terms pertaining to "Miller Fisher syndrome," "Miller Fisher," "Fisher syndrome," and "anti-GQ1b antibody."

Results

An extensive bibliography was researched and summarized in the review from an initial profile of MFS since its description to the recent accounts of diagnosis in COVID-19 patients. MFS is an immune-mediated disease with onset most frequently following infection. Anti-ganglioside GQ1b antibodies, detected in ~85% of patients, play a role in the pathogenesis of the syndrome. There are usually no abnormalities in MFS through routine neuroimaging. In rare cases, neuroimaging shows nerve root enhancement and signs of the involvement of the central nervous system. The most consistent electrophysiological findings in MFS are reduced sensory nerve action potentials and absent H reflexes. Although MFS is generally self-limited and has excellent prognosis, rare recurrent forms have been documented.

Conclusion

This article gives an updated narrative review of MFS with special emphasis on clinical characteristics, neurophysiology, treatment, and prognosis of MFS patients.

Beyond the Ordinary: An Atypical Guillain-Barré Syndrome Case With Unique Characteristics

We present a patient with pharyngeal-cervical-brachial Guillain-Barré syndrome (PCB-GBS) that progressed to a severe state followed by a quick recovery after treatment. This unique clinical course has not been documented previously and provides a potentially invaluable description of a novel GBS variant. A 42-year-old man arrived at the emergency department with a 24-hour history of dysphagia, weakness in his right arm, and bilateral shoulder weakness. Nerve conduction velocity testing revealed bilateral sensory and motor polyneuropathy, leading to the diagnosis of GBS with the PCB variant. Timely diagnosis and plasmapheresis treatment contributed to a complete recovery of muscle strength and reflexes. In cases resembling ours, it is imperative to contemplate the existence of rare Guillain-Barré variants. This case underscores the necessity of recognizing and addressing rare Guillain-Barré variants in clinical settings with similar presentations.

High-resolution MR imaging of cranial neuropathy in patients with anti-GQ1b antibody syndrome

OBJECTIVE

The value of conventional MRI in patients anti-GQ1b antibody syndrome is subject to debate. Our purpose was to evaluate the diagnostic accuracy of high-resolution MRI for detecting cranial nerve abnormalities in patients with anti-GQ1b antibody syndrome.

MATERIALS AND METHODS

This retrospective cohort study enrolled 15 anti-GQ1b-positive patients diagnosed with MFS and related disorders and 17 age-matched controls, all of whom underwent high-resolution MR imaging including pre-contrast and contrast-enhanced (CE) 3D FLAIR and 3D CE T1-weighted turbo field echo (T1-TFE) between 2010 and 2016. The diagnostic performance of high-resolution MRI was assessed using the area under the curve (AUC) of the receiver operating characteristics curve. Inter- and intraobserver agreements were calculated using kappa statistics and intraclass correlation coefficients (ICC), respectively.

RESULTS

Ophthalmoplegia, ataxia, and hypo/areflexia were present in 100%, 60%, and 67%, respectively. Other neurologic findings included ptosis (40%), mydriasis (13%), and facial (27%) and bulbar (13%) palsy. Fourteen of sixteen (88%) MR examinations in 15 patients demonstrated at least one cranial nerve abnormality corresponding to the clinical findings. The involved cranial nerves on MRI were the IIIrd cranial nerve in 14 patients, VIth in nine, VIIth in four, Vth in one, and VIIIth in one. AUC values for detecting cranial neuropathy on high-resolution MRI were 0.938 (95% CI: 0.795-0.992) on a per patient basis. Inter- and intraobserver agreements were 0.842 and 0.945, respectively.

CONCLUSION

High-resolution 3D FLAIR and CE 3D T1-TFE MRI has high reliability and accuracy for demonstrating cranial neuropathy in patients with anti-GQ1b antibody syndrome.

Classic and overlapping Miller-Fisher syndrome: clinical and electrophysiological features in Mexican adults

Classic and overlapping Miller-Fisher syndrome (MFS) have divergent clinical courses. Few studies have addressed the electrophysiological evaluation of MFS patients, most of them carried out in Asia. This work describes and compares their clinical and neurophysiological characteristics. From a Guillain-Barré syndrome (GBS) patient cohort, we made a selection of twenty MFS cases. We defined classic and overlapping MFS, as stated by Wakerley et al. (Nat Rev Neurol 10(9):537-544, 2014). We describe and compare clinical, biochemical, and electrodiagnostic parameters between groups. Seventy-five percent were men, mean age was 42.2 ± 13.6 years, and 45% had a Hughes score ≥ 3. MFS/GBS was the most frequent clinical subtype with 50%. Almost one-third had unaltered electrophysiological studies. Comparative analysis between groups showed statistically significant differences in length of stay, dysautonomia presence, and treatment type. Kaplan-Meier survival analysis showed that 100% of the patients had an independent walk at 3 months. This study reports Mexican MFS patient's characteristics and represents the most extensive case series in Latin America. We observed a high proportion of overlapping syndromes, a good recovery profile, and no significant severe complications.

Pediatric Miller Fisher Syndrome; Characteristic Presentation and Comparison with Adult Miller Fisher Syndrome

Background: We aimed to investigate the characteristic presentation of Miller Fisher syndrome (MFS) in pediatrics and compare it with that in adults. Methods: We performed a retrospective review of medical records, laboratory findings, and disease course of pediatric MFS. The data were compared with those of adult MFS, and literature review was done. Unpaired and paired comparisons between groups were made using Wilcoxon rank-sum and signed-rank tests, respectively. Results: Median age for pediatric MFS was 9.8 ± 6.5 years. There were 5 (45.5%) male and 6 (54.5%) female patients. All patients had preceding infection. Two patients (22.2%) had tested positive for anti-GQ1b antibody. Ten patients (90.1%) were treated with intravenous immunoglobulin, and 2 (18.2%) also received intravenous methylprednisolone. Within one month, 8 (72.7%) patients showed recovery, and all 11 (100%) recovered fully within 3 months. Further, the pediatric group had higher frequency of unilateral involvement of ophthalmoplegia, ataxia, and autonomic symptoms but lower antiganglioside antibody positivity and manifestations of areflexia than the adult group. Conclusions: Neuro-ophthalmic manifestations and disease course of pediatric MFS were similar to those of adult MFS as stated in the literature. However, the presence of autonomic symptoms was higher and anti-GQ1b antibody positivity was lower in pediatric MFS than in adult MFS.

Clinical neurophysiology and cerebrospinal liquor analysis to detect Guillain-Barré syndrome and polyneuritis cranialis in COVID-19 patients: A case series

We report a case series of five patients affected by SARS‐CoV‐2 who developed neurological symptoms, mainly expressing as polyradiculoneuritis and cranial polyneuritis in the 2 months of COVID‐19 pandemic in a city in the northeast of Italy. A diagnosis of Guillain‐Barré syndrome was made on the basis of clinical presentation, cerebrospinal fluid analysis, and electroneurography. In four of them, the therapeutic approach included the administration of intravenous immunoglobulin (0.4 g/kg for 5 days), which resulted in the improvement of neurological symptoms. Clinical neurophysiology revealed the presence of conduction block, absence of F waves, and in two cases a significant decrease in amplitude of compound motor action potential compound muscle action potential (cMAP). Four patients presented a mild facial nerve involvement limited to the muscles of the lower face, with sparing of the forehead muscles associated to ageusia. In one patient, taste assessment showed right‐sided ageusia of the tongue, ipsilateral to the mild facial palsy. In three patients we observed albuminocytological dissociation in the cerebrospinal fluid, and notably, we found an increase of inflammatory mediators such as the interleukin‐8. Peripheral nervous system involvement after infection with COVID‐19 is possible and may include several signs that may be successfully treated with immunoglobulin therapy.

Neurological symptoms may be common in COVID‐19 patients

Neurophysiological assessment is fundamental for a correct diagnosis

Peripheral nervous system involvement is possibile in people with COVID‐19

In these patients, intravenous immunoglobulin administration is a safe and efficient therapy

Electrophysiological subtypes and associated prognosis factors of Mexican adults diagnosed with Guillain-Barré syndrome, a single center experience

BACKGROUND

The clinical characteristics of electrophysiological subtypes and prognostic factors of Mexican adults diagnosed with Guillain-Barré Syndrome (GBS) have not been described.

MATERIALS AND METHODS

A single center, ambispective, cohort study was performed (2015-2019). GBS was defined following the Asbury and Cornblath criteria. Electrodiagnosis was made according to Hadden criteria. Clinical, biochemical and electrodiagnostic parameters were described, compared and analyzed using a multivariate model. Only patients who completed a 3-month follow-up were included.

RESULTS

137 GBS patients (92 males; mean age 46.6 ± 16.6).132 (96.3%) underwent an electrodiagnostic assessment.68 (51.5%) were classified as axonal GBS, with further classified into two groups: acute motor axonal neuropathy (AMAN) 45.4%, and acute motor and sensory axonal neuropathy (AMSAN) 8,6%. The following characteristics were lower in the AMAN group: Medical Research Counsel sumscore (MRC) 30.1 ± 16.3 vs 36.4 ± 14.4, unilateral facial palsy 10% vs 25.9% and albuminocytologic dissociation 41.3% vs. 71.7%.Multivariate analysis found AMAN as an independent predictor of an unfavorable outcome OR: 3.34 (p = 0.03) CONCLUSIONS: AMAN subtype is the most frequent presentation of GBS in Mexican adult patients and an independent predictor of inability to walk independently at 3 months after discharge.

Atypical case of Miller-Fisher syndrome presenting with severe dysphagia and weight loss

A 71-year-old man developed dysphagia, bilateral lower extremity muscle weakness and weight loss. He was admitted to the hospital after a failed formal swallow evaluation, nearly 3 weeks after symptom onset. In addition to dysphagia and weakness, physical examination was notable for hypophonia, dysarthria, diplopia, horizontal ophthalmoparesis, ptosis, ataxia and hyporeflexia. Cerebrospinal fluid was notable for albuminocytological dissociation and serum anti-GQ1b antibody titre was elevated (1:200). A diagnosis of Miller-Fisher syndrome (MFS) was made, and the patient was treated with intravenous immunoglobulin (0.4 g/kg/day) for 5 days, which resulted in resolution of symptoms. This is an atypical case of MFS, in that the presenting symptom was progressive dysphagia rather than the ophthalmoplegia and ataxia that are normally seen in MFS. Patients who present with dysphagia should receive a thorough neurological examination, with particular attention to extraocular movements, reflexes and gait stability, to rule out MFS as a potential cause.

Axonal variants of Guillain-Barré syndrome: an update

Axonal variants of Guillain-Barré syndrome (GBS) mainly include acute motor axonal neuropathy, acute motor and sensory axonal neuropathy, and pharyngeal-cervical-brachial weakness. Molecular mimicry of human gangliosides by a pathogen's lipooligosaccharides is a well-established mechanism for Campylobacter jejuni-associated GBS. New triggers of the axonal variants of GBS (axonal GBS), such as Zika virus, hepatitis viruses, intravenous administration of ganglioside, vaccination, and surgery, are being identified. However, the pathogenetic mechanisms of axonal GBS related to antecedent bacterial or viral infections other than Campylobacter jejuni remain unknown. Currently, autoantibody classification and serial electrophysiology are cardinal approaches to differentiate axonal GBS from the prototype of GBS, acute inflammatory demyelinating polyneuropathy. Newly developed technologies, including metabolite analysis, peripheral nerve ultrasound, and feature selection via artificial intelligence are facilitating more accurate diagnosis of axonal GBS. Nevertheless, some key issues, such as genetic susceptibilities, remain unanswered and moreover, current therapies bear limitations. Although several therapies have shown considerable benefits to experimental animals, randomized controlled trials are still needed to validate their efficacy.

Anti-Ganglioside Antibody-Negative Miller Fisher and AMSAN Variant Guillain-Barré Overlap Syndrome

A case of Miller Fisher and acute motor sensory axonal neuropathy (AMSAN) variant Guillain-Barré (MFS/AMSAN-GBS) overlap syndrome is presented. The neurological presentation of the overlap syndrome was preceded by an upper respiratory tract infection. Eventually, severe weakness of bulbar and limb muscles, areflexia, ophthalmoplegia, ataxia, and respiratory insufficiency developed. The electroneuromyography revealed symmetrical axonal polyneuropathy which was dominant in both upper limbs. Although a panel of anti-ganglioside antibodies including anti-GQ1b was negative, immediate treatment with intravenous immunoglobulin resulted in dramatic response.

Diagnosis and management of Guillain-Barré syndrome in ten steps

Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diagnostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae.

Advances in management of Guillain-Barré syndrome

PURPOSE OF REVIEW

The clinical presentation of Guillain-Barré syndrome (GBS) is highly variable, which can make the diagnosis challenging. Intravenous immunoglobulin (IVIg) and plasma exchange are the cornerstones of treatment since decades. But despite these treatments, 25% initially progress in muscle weakness, 25% require artificial ventilation, 20% is still not able to walk independently after 6 months, and 2-5% die, emphasizing the need for better treatment. We summarize new developments regarding the diagnosis, prognosis, and management of GBS.

RECENT FINDINGS

GBS is a clinical diagnosis that can be supported by cerebrospinal fluid examination and nerve conduction studies. Nerve ultrasound and MRI are potentially useful techniques to diagnose inflammatory neuropathies. Several novel infections have recently been associated to GBS. Evidence from experimental studies and recent phase 2 clinical trials suggests that complement inhibition combined with IVIg might improve outcome in GBS, but further studies are warranted. Prognostic models could guide the selection of patients with a relatively poor prognosis that might benefit most from additional IVIg or otherwise intensified treatment.

SUMMARY

New diagnostic tools may help to have early and accurate diagnosis in difficult GBS cases. Increased knowledge on the pathophysiology of GBS forms the basis for development of new, targeted, and personalized treatments that hopefully improve outcome.

A rare mimic of acute stroke: rapidly progressing Miller-Fisher Syndrome to acute motor and sensory axonal neuropathy variant of Guillain-Barre Syndrome

Ophthalmoplegia, ataxia and areflexia characterise the clinical triad of Miller-Fisher Syndrome (MFS). When the disease presents acutely, it can mimic posterior circulation stroke. We describe a case of an adult patient presenting with sudden dizziness, diplopia, vomiting, and loss of balance. She was initially managed as a case of a brainstem stroke, but the progression of craniopathies without deterioration in sensorium coupled with areflexia clinched the diagnosis of MFS two days into her admission. On the third day, her MFS progressed rapidly to acute motor and sensory axonal neuropathy (AMSAN) variant of Guillain-Barre Syndrome, a rare occurrence in patients with MFS, with only four reported cases including our own. Among the four cases, ours is the only one still non-ambulatory eight months after the initial onset of symptoms. The case highlights the importance of early recognition of MFS in patients with ophthalmoplegia and ataxia despite initially normal reflexes.

Area postrema syndrome as frequent feature of Bickerstaff brainstem encephalitis

Objective

Area postrema (AP) syndrome (defined as: nausea and/or emesis and/or singultus at onset of brainstem dysfunction) comprises complex pathophysiologic mechanisms triggered by different entities. The first objective was to assess the frequency of AP syndrome as a clinical feature in brainstem encephalitis (BE). Finding an especially high prevalence of AP syndrome in Bickerstaff brainstem encephalitis (BBE), we also analyzed the frequency of AP syndrome in other autoimmune diseases with anti-ganglioside antibodies (Guillain-Barré syndrome (GBS) and its variants).

Methods

We systematically evaluated the prevalence of AP syndrome in BE in all patients treated at our university hospital during a 15-year period. In a second step, BBE patients were compared to GBS and Miller Fisher syndrome (MFS) patients as clinical subtypes of a disease continuum without brainstem dysfunction.

Results

We found AP syndrome in 8 of 21 BE patients, including 3 of 7 BBE and in 4 of 112 GBS/MFS patients. AP syndrome was as a frequent but under-recognized feature of BE with a significant impact on patients' well being.

Interpretation

Manifestation of AP syndrome in BBE but also in GBS and its subtypes point toward a role of autoimmune antibodies that should be investigated in future studies. Considerable misdiagnosis or nonrecognition complicates diagnostic and therapeutic management. Therefore, AP syndrome should be considered in any episode of otherwise unexplained nausea, emesis, or singultus.

[Bickerstaff's encephalitis]

A clinical case of Bickerstaff encephalitis, an autoimmune neuropathy, which affects central and peripheral nerve systems, is presented. This article describes problems of the diagnosis and treatment of the disease. Results of MRI, PET, electrophysiological and immunological studies are presented.

Miller Fisher syndrome, Bickerstaff brainstem encephalitis and Guillain-Barré syndrome overlap with persistent non-demyelinating conduction blocks: a case report

Background

Miller Fisher syndrome (MFS) and Bickerstaff’s Brainstem Encephalitis (BBE) share some clinical features and a common immunological profile characterized by anti-GQ1b antibodies. Some MFS patients overlap with Guillain-Barré syndrome (GBS) or BBE. We report a patient with MFS, BBE, and axonal GBS overlap in whom serial electrophysiological studies showed persistent motor conduction blocks (CBs).

Case presentation

A 61-year-old man acutely developed ophtalmoparesis, ataxia and areflexia suggesting MFS. Paresthesias, severe weakness, and drowsiness rapidly developed indicating an overlap with BBE and GBS. Preceding infection with Mycoplasma Pneumoniae and anti-GQ1b antibodies were detected. On day 4, nerve conduction study showed reduced or non-recordable compound muscle action potentials (CMAPs) and sensory nerve action potentials (SNAPs) without demyelinating features, indicating the electrodiagnosis of acute motor and sensory axonal neuropathy and suggesting a poor prognosis. Intravenous immunoglobulins (IVIg) were given but clinical status worsened to ophthalmoplegia, tetraplegia and coma needing mechanical ventilation. A second IVIg course was given and the patient was weaned off ventilation on day 41 and transferred to rehabilitation on day 57 with partial resolution of the ophthalmoplegia and limited recovery of muscle strength. Electrophysiology showed, after 10 weeks, greatly improved distal CMAP amplitudes suggesting the resolution of distal CBs while CBs in intermediate and proximal nerve segments emerged. CBs unusually persisted for four to 6 months without development of abnormal temporal dispersion. A third IVIg course was started on day 179 and the resolution of CBs mirrored the clinical improvement.

Conclusions

GQ1b gangliosides are expressed in the nodal region of oculomotor nerves, muscle spindle afferents, peripheral nerves and possibly in the brainstem reticular formation. Anti-GQ1b antibodies may explain the complex symptomatology and the overlap between MFS, BBE, and GBS.

CBs that persisted and recovered without the development of temporal dispersion suggest that weakness was due to a sustained, antibody-mediated, attack at the nodal region inducing a non-demyelinating conduction failure as expression of an acute onset, long lasting, nodopathy. Serial electrophysiological studies allowed not only to understand the underlying pathophysiology and formulate a more correct prognosis but also to guide the treatment.

Guillain-Barré Syndrome, variants & forms fruste: Reclassification with new criteria

OBJECTIVES

This study aimed to evaluate the clinical and electrophysiological characteristics of various distinctive classical and localised Guillain-Barré syndrome (GBS) subtypes.

PATIENTS AND METHODS

Clinical characteristics and electrophysiological data of sixty-one consecutive patients admitted between 2012 and 2015 were systematically analysed and reclassified according to the new GBS clinical classification. Neurophysiology was evaluated with Hadden et al.'s vs recently proposed Rajabally et al.'s criteria. Functional severity and clinical outcome of various GBS subtypes were ascertained.

RESULTS

All patients initially identified as GBS or related disorders can be sub-classified into having classical GBS (41, 67%), classic Miller-Fisher Syndrome (MFS) (6, 10%), Pharyngeal-cervical-brachial (PCB) (3, 5%), paraparetic GBS (4, 7%), bifacial weakness with paresthesia (3, 5%), acute ophthalmoparesis (AO) (1, 2%) and overlap syndrome (3, 5%): one (2%) with GBS/Bickerstaff brainstem encephalitis overlap and 2 (3%) with GBS/MFS overlap. Greater proportion of axonal classical GBS (67% vs 55%, p=0.372) seen with Rajabally et al.'s criteria and a predominantly axonal form of paraparetic variant (75%) independent of electrodiagnostic criteria were more representative of Asian GBS cohort. Classical GBS patients had lowest admission and discharge Medical Research Council Sum Score (MRCSS), greater functional disability and longest length of in-patient stay. Twenty (20/21, 95%) patients who needed mechanical ventilation had classical GBS. Patients required repeated dose of intravenous immunoglobulin (5/6, 3%) or plasma exchange (4/4, 100%) more frequently had axonal form of classical GBS.

CONCLUSION

Phenotype recognition based on new GBS clinical classification, supported by electrodiagnostic study permits more precise clinical subtypes determination and outcome prognostication.

Treatment dilemmas in Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an acute polyradiculoneuropathy with a highly variable clinical course and outcome. Intravenous immunoglobulin (IVIg) and plasma exchange are proven effective treatments, but the efficacy has been demonstrated mainly on motor improvement in adults with a typical and severe form of GBS. In clinical practice, treatment dilemmas may occur in patients with a relatively mild presentation, variant forms of GBS, or when the onset of weakness was more than 2 weeks ago. Other therapeutic dilemmas may arise in patients who do not improve or even progress after initial treatment. We provide an overview of the current literature about therapeutic options in these situations, and additionally give our personal view that may serve as a basis for therapeutic decision-making.

Acute Ataxia in Children: A Review of the Differential Diagnosis and Evaluation in the Emergency Department

Acute ataxia in a pediatric patient poses a diagnostic dilemma for any physician. While the most common etiologies are benign, occasional individuals require urgent intervention. Children with stroke, toxic ingestion, infection, and neuro-inflammatory disorders frequently exhibit ataxia as an essential-if not the only-presenting feature. The available retrospective research utilize inconsistent definitions of acute ataxia, precluding the ability to pool data from these studies. No prospective data exist that report on patients presenting to the emergency department with ataxia. This review examines the reported causes of ataxia and attempts to group them into distinct categories: post-infectious and inflammatory central and peripheral phenomena, toxic ingestion, neurovascular, infectious and miscellaneous. From there, we synthesize the existing literature to understand which aspects of the history, physical exam, and ancillary testing might aid in narrowing the differential diagnosis. MRI is superior to CT in detecting inflammatory or vascular insults in the posterior fossa, though CT may be necessary in emergent situations. Lumbar puncture may be deferred until after admission in most instances, with suspicion for meningitis being the major exception. There is insufficient evidence to guide laboratory evaluation of serum, testing should be ordered based on clinical judgement-recommended studies include metabolic profiles and screening labs for metabolic disorders (lactate and ammonia). All patients should be reflexively screened for toxic ingestions.

Electrophysiology in Fisher syndrome

Fisher syndrome (FS), a variant of Guillain-Barré syndrome (GBS), is characterized by the clinical triad of ophthalmoplegia, ataxia, and areflexia. The lesion sites for these unique clinical features include the oculomotor nerves and group 1a neurons in the dorsal root ganglion, and the presence of FS is determined by the expression of ganglioside GQ1b in the human nervous system. Neurophysiological findings suggest that ataxia and areflexia are due to an impaired proprioceptive afferent system. Typically, the soleus H-reflex is absent and a body-sway analysis using posturography shows a 1-Hz peak, which indicates proprioception dysfunction. Sensory nerve action potentials and somatosensory-evoked potentials are abnormal in approximately 30% of FS patients, indicating the occasional involvement of cutaneous (group 2) afferents. During the disease course, approximately 15% of FS patients suffer an overlap of axonal GBS with nerve conduction abnormalities that reflect axonal dysfunction. This review summarizes electrophysiological abnormalities and their clinical significance in FS.

[An overlap case of Fisher syndrome and pharyngeal-cervical-brachial variant of Guillain-Barré syndrome associated with urinary retention and constipation]

We report a 28-year-old woman with the overlap of Fisher syndrome and pharyngeal-cervical-brachial variant of Guillain-Barré syndrome associated with urinary retention and constipation. She showed total ophthalmoplegia, dysphagia, dysarthria, upper extremity weakness, cerebellar ataxia, slightly diminished superficial sensations in her hands and feet, urinary retention and constipation 14 days after preceding infection. Laboratory data showed elevations of antiganglioside antibodies to GT1b, GD1b, GQ1b, GD3 and GT1a in the IgG subclass. There was slight elevation of protein with no pleocytosis in cerebrospinal fluid. After administration of intravenous immunoglobulin (IVIg), only the titer of antiganglioside antibody to GQ1b was decreased, and she showed rapid improvement in dysphagia, urinary retention and constipation, and slow recovery in ophthalmoplegia and cerebellar ataxia. The elevations of antiganglioside antibodies to GQ1b may be pathologically related to autonomic involvement such as urinary retention and constipation in that IVIg seems to be effective. The present case suggests that GQ1b may also locate in the autonomic nerve that plays bladder and defecation functions, and that incidence of neurological symptoms and the response of treatment may differ according to each GQ1b localization.

What's in the Literature?

The Guillain-Barré syndrome (GBS) is one of the few neuropathies well known to the general public, in part because of its association with swine flu vaccinations in 1976. GBS has again reached the general public with its possible association with Zika virus. The virus, borne by infected Aedes aegypti mosquitos, is being linked to birth defects when pregnant women are bitten and infected. There are early reports also linking GBS to Zika infection, which could expose a wider range of infected people to the neuropathy. This summer infected Aedes mosquitos will likely reach southern portions of the United States, and travelers to countries where Aedes is endemic will increase. It is important to appreciate that the neurologic consequences of Zika virus are being actively investigated, and firm associations and consequences are yet to be established. Small fiber neuropathies are common and can be due to a number of underlying diseases, and a recent review also indicates that many are idiopathic. One cause is Sjögren syndrome, and a case series reviews clinical features. The diagnosis and underlying features of primary lateral sclerosis are a clinical challenge. Similarities between primary lateral sclerosis and hereditary spastic paraparesis (HSP) have long been noted. With a wide spectrum of gene mutations associated with HSP, clinical distinction between the 2 disorders is problematic. A review covers the wide spectrum of HSP. With no cure, the progression of amyotrophic lateral sclerosis (ALS) to respiratory failure is predictable. This could easily result in marked depression among patients, and 2 studies have explored the frequency and severity of depression. The cause of ALS remains unknown, and when no hereditary factor is apparent, environmental questions arise as possible contributing factor(s). The most notable association is with military service, although specific occupational or environmental linkages are not well sorted out. Two recent reports address these issues. There is good news for ALS patients with muscle cramps with the results of a multicenter randomized and placebo-controlled trial showing that mexiletine is effective in reducing this common symptom. The treatment of myasthenia gravis with various agents, the use of patient-reported outcome measures in myasthenia gravis, and the occurrence of myocarditis in this disease are reviewed. Necrotizing autoimmune neuropathies, the co-occurrence of inclusion body myositis and a form of T-cell leukemia are discussed as are valosin-containing protein (VCP)-opathy and bone health in patients with dystrophinopathy.