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When the diagnosis of myasthenia gravis (MG) has been secured, the aim of management should be prompt symptom control and the induction of remission or minimal manifestations. Symptom control, with acetylcholinesterase inhibitors such as pyridostigmine, is commonly employed. This may be sufficient in mild disease. There is no single universally accepted treatment regimen. Corticosteroids are the mainstay of immunosuppressive treatment in patients with more than mild MG to induce remission. Immunosuppressive therapies, such as azathioprine are prescribed in addition to but sometimes instead of corticosteroids when background comorbidities preclude or restrict the use of steroids. Rituximab has a role in refractory MG, while plasmapheresis and immunoglobulin therapy are commonly prescribed to treat MG crisis and in some cases of refractory MG. Data from the MGTX trial showed clear evidence that thymectomy is beneficial in patients with acetylcholine receptor (AChR) antibody positive generalized MG, up to the age of 65 years. Minimally invasive thymectomy surgery including robotic-assisted thymectomy surgery has further revolutionized thymectomy and the management of MG. Ocular MG is not life-threatening but can be significantly disabling when diplopia is persistent. There is evidence to support early treatment with corticosteroids when ocular motility is abnormal and fails to respond to symptomatic treatment. Treatment needs to be individualized in the older age-group depending on specific comorbidities. In the younger age-groups, particularly in women, consideration must be given to the potential teratogenicity of certain therapies. Novel therapies are being developed and trialed, including ones that inhibit complement-induced immunological pathways or interfere with antibody-recycling pathways. Fatigue is common in MG and should be duly identified from fatigable weakness and managed with a combination of physical therapy with or without psychological support. MG patients may also develop dysfunctional breathing and the necessary respiratory physiotherapy techniques need to be implemented to alleviate the patient's symptoms of dyspnoea. In this review, we discuss various facets of myasthenia management in adults with ocular and generalized disease, including some practical approaches and our personal opinions based on our experience., (Copyright © 2020 Farrugia and Goodfellow.)

Autoimmune encephalitis is emerging as an important and relatively common cause of encephalitis in the developed world. Crucially, early recognition and prompt initiation of a range of immunotherapies is likely to improve the outcomes of patients with autoimmune encephalitis, particularly for those with identifiable antibodies against neuronal cell surface proteins. There are a rapidly growing number of specific autoantibodies and associated syndromes, but many of these remain very rare. The majority of cases comprise anti-N-methyl-D-aspartate (NMDA) receptor encephalitis or anti-leucine-rich glioma-inactivated protein 1 (LGI1) encephalitis with the remaining cases a mixture of over 10 other specific antibodies or being seronegative. The core anti-NMDA encephalitis phenotype is a distinct symptom complex involving psychiatric and neurological features and anti-LGI1 encephalitis presents with cognitive changes and distinct seizure types. Diagnosis can be delayed owing to limited access to specialised laboratory testing or in cases with atypical or limited features., Competing Interests: JAG is Chief Executive Officer and holds equity in Abaxon Biologics, a biopharmaceutical company developing novel therapies in autoimmune and other diseases. JAG and GAM have received funding from Tenovus Scotland to help establish a prospective patient register for people with autoimmune encephalitis.

A wide range of neuroimmunological diseases, referred to as autoimmune neuropathies, affect the peripheral nervous systems (PNS). The PNS is structurally diverse with complex anatomical compartments enriched in many different myelin and neuronal glycolipids, notably gangliosides. Autoimmune neuropathies are a proportion of autoimmune neuropathies mediated by autoimmune attack due to antibodies reactive with these compartmentally localized gangliosides. Antiganglioside antibodies are principally associated with the acute paralytic disease, Guillain-Barré syndrome, and are also found in several chronic autoimmune neuropathy syndromes. These antibodies may arise spontaneously from the natural autoantibody repertoire, or be induced by infections that share structurally similar glycans to gangliosides, an immunological process often referred to as molecular mimicry. The principal infection exhibiting this structural similarity is Campylobacter jejuni, which displays mimics of GM1, GD1a, GT1a, and other gangliosides on its surface lipo-oligosaccharide. Autoantibodies thus induced bind glycan epitopes on peripheral nerve gangliosides where they activate complement and recruit macrophages, causing structural and functional disorganization of nerve conduction. Chronic autoimmune neuropathies are also associated with naturally arising IgM antibodies directed against ganglioside epitopes present on disialylated gangliosides, that induce a sensory neuropathy, and on GM1, that induce a motor neuropathy. In a third syndrome, the so-called "anti-MAG" neuropathy, the antibodies bind a sulfated glucuronic acid epitope present on myelin-associated glycoprotein and the glycolipid sulfated glucuronyl paragloboside. This review will describe the immunological, pathological, and clinical features of these disorders in the context of our broader knowledge of the ganglioside glycobiology of the peripheral nervous system., (Copyright © 2018. Published by Elsevier Inc.)

The outcome of Guillain-Barré syndrome (GBS) remains unchanged since plasma exchange and intravenous immunoglobulin (IVIg) were introduced over 20 years ago. Pathogenesis studies on GBS have identified the terminal component of complement cascade as a key disease mediator and therapeutic target. We report the first use of terminal complement pathway inhibition with eculizumab in humans with GBS. In a randomised, double-blind, placebo-controlled trial, 28 subjects eligible on the basis of GBS disability grade of at least 3 were screened, of whom 8 (29%) were randomised. Five received eculizumab for 4 weeks, alongside standard IVIg treatment. The safety outcomes, monitored via adverse events capture, showed eculizumab to be well-tolerated and safe when administered in conjunction with IVIg. Primary and secondary efficacy outcomes in the form of GBS disability scores (GBS DS), MRC sum scores, Rasch overall disability scores, and overall neuropathy limitation scores are reported descriptively. For the primary efficacy outcome at 4 weeks after recruitment, two of two placebo- and two of five eculizumab-treated subjects had improved by one or more grades on the GBS DS. Although the small sample size precludes a statistically meaningful analysis, these pilot data indicate further studies on complement inhibition in GBS are warranted., (© 2016 Peripheral Nerve Society.)

In 1916, Guillain, Barré and Strohl reported on two cases of acute flaccid paralysis with high cerebrospinal fluid protein levels and normal cell counts - novel findings that identified the disease we now know as Guillain-Barré syndrome (GBS). 100 years on, we have made great progress with the clinical and pathological characterization of GBS. Early clinicopathological and animal studies indicated that GBS was an immune-mediated demyelinating disorder, and that severe GBS could result in secondary axonal injury; the current treatments of plasma exchange and intravenous immunoglobulin, which were developed in the 1980s, are based on this premise. Subsequent work has, however, shown that primary axonal injury can be the underlying disease. The association of Campylobacter jejuni strains has led to confirmation that anti-ganglioside antibodies are pathogenic and that axonal GBS involves an antibody and complement-mediated disruption of nodes of Ranvier, neuromuscular junctions and other neuronal and glial membranes. Now, ongoing clinical trials of the complement inhibitor eculizumab are the first targeted immunotherapy in GBS.

Purpose of Review: There has been a recent renewed interest in the prevalence of antiglycolipid antibodies and their associations with specific clinical phenotypes in Guillain-Barré syndrome. Recent reports have sought to confirm and expand the antibody-phenotype associations of antiganglioside antibodies, antiganglioside-complex antibodies, and antiglycolipid-complex antibodies in the various acute immune-mediated neuropathies. This is a rapidly developing field with technical advances in assay methodology, which have resulted in numerous new putative antibody-phenotype associations., Recent Findings: Antibodies against single ganglioside species remain the most established serological marker of Guillain-Barré syndrome and its myriad clinical variants. Antibodies against combinations of gangliosides, ganglioside-complex antibodies, detected by the ELISA method have emerged as putative markers of certain clinical features or pathological subtypes, specifically acute motor axonal neuropathy, but do not seem to greatly increase the diagnostic sensitivity of antibody testing as most also react with single ganglioside species. The novel assay method of the combinatorial glycoarray allows high-throughput detection of antibodies recognizing combinations of gangliosides and other glycolipids and early studies suggest it identifies antibody-phenotype associations in addition to significantly increasing the sensitivity of serological testing, including for the acute inflammatory demyelinating polyneuropathy variant., Summary: Antibodies against single ganglioside species remain diagnostically useful in routine clinical practice. Antibodies against ganglioside complexes, or gangliosides and other glycolipid complexes, are emerging as useful markers of various clinic features and pathological subtypes; however, the precise associations remain to be fully delineated and confirmed. The antibody-complex detection methods are rapidly evolving but in most centres are not yet available in routine clinical practice.

The importance of elevated or low arterial blood pressure (BP) early after stroke, and the need for pharmacological intervention to control BP, remains controversial. Debate surrounds if, when and how to intervene. This debate is informed by conflicting results from observational data and underpowered clinical trials and substantive outcome data are lacking. Accordingly, management decisions have largely been left up to the individual treating physician and guidelines are based on 'good practice' and theory rather than level 1, grade A evidence. Substantial progress has been made in recent years, particularly in the field of hemorrhagic stroke, where recently presented and soon to completed large-scale trials may finally give us a firm evidence base. For ischemic stroke, many important studies have informed our understanding of the basic pathophysiology, epidemiology, treatment and outcomes of BP management in acute stroke and, although not yet constituting a solid 'evidence base', are helping us from the 'cognitive quick-sand' of small studies and personal experiences.

Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes is a progressive, multisystem mitochondrial disease affecting children and young adults. Patients acquire disability through stroke-like episodes and have an increased mortality. Eighty per cent of cases have the mitochondrial mutation m.3243A>G which is linked to respiratory transport chain dysfunction and oxidative stress in energy demanding organs, particularly muscle and brain. It typically presents with seizures, headaches and acute neurological deficits mimicking stroke. It is an important differential in patients presenting with stroke, seizures, or suspected central nervous system infection or vasculitis. Investigations should exclude other aetiologies and include neuroimaging and cerebrospinal fluid analysis. Mutation analysis can be performed on urine samples. There is no high quality evidence to support the use of any of the agents reported in small studies. This article summarises the core clinical, biochemical, radiological and genetic features and discusses the evidence for a number of potential therapies.

Background: Despite the inevitability of disease progression in amyotrophic lateral sclerosis, there is a high degree of prognostic heterogeneity in all subtypes. Some bulbar-onset (BO) patients may develop rapid anarthria yet remain ambulant for a prolonged period, whereas others progress rapidly, with early generalisation of motor weakness to the limbs and respiratory muscles. Diagnostic delay is a common occurrence in ALS, and many BO patients report having attended other specialist clinics prior to diagnosis., Methods: A retrospective descriptive study of BO ALS patients seen in a tertiary clinic over a six year period., Results: Forty-nine BO ALS patients were studied. Median survival from symptom onset was 27 months (range 6-84). 63% of subjects were female and the mean age at symptom onset was 68 years. Half had been referred to another speciality prior to diagnosis, either otolaryngology or stroke clinics, but this did not influence diagnostic latency or survival. Emotionality was reported in 45% of patients. Neurophysiological assessment was performed in 80%, brain imaging recorded in 69%, and antibody testing for myasthenia gravis in 22%. The median time to symptomatic progression beyond the bulbar region was approximately 1 year, with equal proportions progressing to the upper or lower limbs. The median interval from onset to anarthria was 18 months, and to loss of ambulation 22 months. There was a close correlation between the two (r(2)=0.6) and median survival from loss of ambulation was only 3 months. Gastrostomy was carried out in 78% of patients with a median time of 13 months from symptom onset, and 3 months from diagnosis. Median survival from gastrostomy was 10 months., Conclusions: Survival in bulbar-onset ALS is highly variable. Half of the patients were referred to an inappropriate clinic prior to diagnosis. The time interval to the development of anarthria predicted the timing of subsequent loss of ambulation accurately from which survival may then be only a few months., (Copyright 2010 Elsevier B.V. All rights reserved.)

A newly acquired neuromuscular cause of weakness has been found in 25-85% of critically ill patients. Three distinct entities have been identified: (1) critical illness polyneuropathy (CIP); (2) acute myopathy of intensive care (itself with three subtypes); and (3) a syndrome with features of both 1 and 2 (called critical illness myopathy and/or neuropathy or CRIMYNE). CIP is primarily a distal axonopathy involving both sensory and motor nerves. Electroneurography and electromyography (ENG-EMG) is the gold standard for diagnosis. CIM is a proximal as well as distal muscle weakness affecting both types of muscle fibres. It is associated with high use of non-depolarising muscle blockers and corticosteroids. Avoidance of systemic inflammatory response syndrome (SIRS) is the most effective way to reduce the likelihood of developing CIP or CIM. Outcome is variable and depends largely on the underlying illness. Detailed history, careful physical examination, review of medication chart and analysis of initial investigations provides invaluable clues towards the diagnosis.

The human paralytic neuropathy, Miller Fisher syndrome (MFS) is associated with autoantibodies specific for disialosyl epitopes on gangliosides GQ1b, GT1a, and GD3. Since these gangliosides are enriched in synaptic membranes, anti-ganglioside antibodies may target neuromuscular junctions (NMJs), thereby contributing to disease symptoms. We have shown previously that at murine NMJs, anti-disialosyl antibodies induce an alpha-latrotoxin-like effect, electrophysiologically characterized by transient massive increase of spontaneous neurotransmitter release followed by block of evoked release, resulting in paralysis of the muscle preparation. Morphologically, motor nerve terminal damage, as well as perisynaptic Schwann cell (pSC) death is observed. The relative contributions of neuronal and pSC injury to the paralytic effect and subsequent repair are unknown. In this study, we have examined the ability of subsets of anti-disialosyl antibodies to discriminate between the neuronal and glial elements of the NMJ and thereby induce either neuronal injury or pSC death. Most antibodies reactive with GD3 induced pSC death, whereas antibody reactivity with GT1a correlated with the extent of nerve terminal injury. Motor nerve terminal injury resulted in massive uncontrolled exocytosis with paralysis. However, pSC ablation induced no acute (within 1 h) electrophysiological or morphological changes to the underlying nerve terminal. These data suggest that at mammalian NMJs, acute pSC injury or ablation has no major deleterious influence on synapse function. Our studies provide evidence for highly selective targeting of mammalian NMJ membranes, based on ganglioside composition, that can be exploited for examining axonal-glial interactions both in disease states and in normal NMJ homeostasis., ((c) 2005 Wiley-Liss, Inc.)

Anti-GD1a ganglioside antibodies (Abs) are the serological hallmark of the acute motor axonal form of the post-infectious paralysis, Guillain-Barre syndrome. Development of a disease model in mice has been impeded by the weak immunogenicity of gangliosides and the apparent resistance of GD1a-containing neural membranes to anti-GD1a antibody-mediated injury. Here we used mice with altered ganglioside biosynthesis to generate such a model at motor nerve terminals. First, we bypassed immunological tolerance by immunizing GD1a-deficient, beta-1,4-N-acetylgalactosaminyl transferase knock-out mice with GD1a ganglioside-mimicking antigens from Campylobacter jejuni and generated high-titer anti-GD1a antisera and complement fixing monoclonal Abs (mAbs). Next, we exposed ex vivo nerve-muscle preparations from GD1a-overexpressing, GD3 synthase knock-out mice to the anti-GD1a mAbs in the presence of a source of complement and investigated morphological and electrophysiological damage. Dense antibody and complement deposits were observed only over presynaptic motor axons, accompanied by severe ultrastructural damage and electrophysiological blockade of motor nerve terminal function. Perisynaptic Schwann cells and postsynaptic membranes were unaffected. In contrast, normal mice were not only unresponsive to immunization with GD1a but also resistant to neural injury during anti-GD1a Ab exposure, demonstrating the central role of membrane antigen density in modulating both immune tolerance to GD1a and axonal susceptibility to anti-GD1a Abmediated injury. Identical paralyzing effects were observed when testing mouse and human anti-GD1a-positive sera. These data indicate that anti-GD1a Abs arise via molecular mimicry and are likely to be clinically relevant in injuring peripheral nerve axonal membranes containing sufficiently high levels of GD1a.