Pathogenic role of ganglioside metabolism in neurodegenerative diseases.

Ganglioside metabolism is altered in several neurodegenerative diseases, and this may participate in several events related to the pathogenesis of these diseases. Most changes occur in specific areas of the brain and their distinct membrane microdomains or lipid rafts. Antiganglioside antibodies may be involved in dysfunction of the blood-brain barrier and disease progression in these diseases. In lipid rafts, interactions of glycosphingolipids, including ganglioside, with proteins may be responsible for the misfolding events that cause the fibril and/or aggregate processing of disease-specific proteins, such as α-synuclein, in Parkinson's disease, huntingtin protein in Huntington's disease, and copper-zinc superoxide dismutase in amyotrophic lateral sclerosis. Targeting ganglioside metabolism may represent an underexploited opportunity to design novel therapeutic strategies for neurodegeneration in these diseases.

Ocular Manifestations of Miller Fisher Syndrome: a Case Report.

BACKGROUND: Miller Fisher syndrome (MFS) is a variant of Guillain-Barré syndrome and is characterised by a clinical triad of ophthalmoplegia, ataxia and areflexia. OBJECTIVES: This report presents an atypical case of MFS characterized by ocular and gastrointestinal involvement, and anti-ganglioside antibody-positivity. METHODS: A 17-year old boy was referred to our ophthalmology emergency room with signs and symptoms of diplopia and upper lid ptosis of the right eye. He underwent a complete ophthalmologic examination with special reference to strabologic status, as well as a neuropediatric examination with serum antiganglioside antibody panel. RESULTS: Strabologic examination showed horisontal diplopia (near and far), ptosis of the upper eyelid on the right and bilateral ophthalmoplegia (limited elevation). Orthoptic examination revealed esotropia of 8 prism dioptres (PD) at near and 18 PD at far distance. A pediatric neurologist found normal limb power, deep tendon reflexes and flexor plantar responses, but attenuated right patellar reflex. Serum anti-GQ1b IgG (+++), anti-GQ1b IgM (++) and anti-GD1a IgM(++) were positive. Positivity of anti-GQ1b IgG antibody confirmed the existence of incomplete MFS. We treated the patient with systemic intravenous immunoglobulins for five days, and after five months of follow-up, all symptoms resolved. CONCLUSION: MFS can present itself as a wide range of clinical features and its timely recognition is important. Despite the alarming nature of the disease, patients with MFS tend to have a good recovery of presented symptoms, and without any significant residual deficit.

Acute Unilateral Isolated Oculomotor Nerve Palsy in an Adult Patient with Influenza A.

An otherwise healthy 44-year-old woman exhibited isolated unilateral oculomotor nerve palsy accompanied by an influenza A infection. An intra-orbital MRI scan revealed that her right third intracranial nerve was enlarged and enhanced. She recovered completely during the first month after treatment with oseltamivir phosphate. Although intracranial nerve disorders that result from influenza infections are most frequently reported in children, it is noteworthy that influenza can also cause focal intracranial nerve inflammation with ophthalmoparesis in adults. These disorders can be diagnosed using intra-orbital MRI scans with appropriate sequences and through immunological assays to detect the presence of antiganglioside antibodies.

Diagnostic insights into chronic-inflammatory demyelinating polyneuropathies.

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare immune-mediated neuropathy with demyelination of nerve fibers as leading morphological feature. The course of disease can be chronic progressive or remitting relapsing. Whereas for acute immune-mediated neuropathies several serological markers have been identified and used successfully in clinical routine, the serological diagnosis of chronic variants such as CIDP has not yet been evolved satisfactory. The typical CIDP and its various atypical variants are characterized by a certain diversity of clinical phenotype and response to treatment. Thus, diagnostic markers could aid in the differential diagnosis of CIDP variants and stratification of patients for a better treatment response. Most patients respond well to a causal therapy including steroids, intravenous immunoglobulins and plasmapheresis. Apart from electrophysiological and morphological markers, several autoantibodies have been reported as candidate markers for CIDP, including antibodies against glycolipids or paranodal/nodal molecules. The present review provides a summary of the progress in autoantibody testing in CIDP and its possible implication on the stratification of the CIDP variants and treatment response.

Transient Isolated Lower Bulbar Palsy With Elevated Serum Anti-GM1 and Anti-GD1b Antibodies During Aripiprazole Treatment.

BACKGROUND: Transient bulbar palsy without involvement of the facial or extraocular muscles is a rare presentation. It is considered a form of cranial polyneuropathy, a variant of Guillain-Barré syndrome that is related to the autoimmune mechanisms induced by preceding infections or vaccinations. However, drug-induced cranial polyneuropathy has not previously been reported. We describe a boy with isolated bulbar palsy and positive serum antiganglioside antibodies during aripiprazole treatment. PATIENT DESCRIPTION: This 12-year-old boy was admitted with a seven-day history of dysarthria, tongue discomfort, and tinnitus. Three weeks before symptom onset, aripiprazole was added to the patient's medications for attention-deficit hyperactivity disorder. On examination, he showed curtaining of the pharyngeal wall, tongue fasciculation and deviation, and a weak gag reflex. Cranial magnetic resonance imaging suggested lower cranial nerve involvement. Serum anti-GM1 IgG and anti-GD1b IgG antibodies were positive. After stopping aripiprazole, his bulbar symptoms improved. However, on readministration of aripiprazole seven weeks later, dysarthria recurred and again resolved after stopping the drug. CONCLUSION: We describe the first patient with anti-GM1 IgG and anti-GD1b IgG antibodies-associated transient cranial polyneuropathy presenting as isolated bulbar palsy. These findings could be an adverse effect of aripiprazole treatment.

A Prospective, Multicenter, Randomized Phase II Study to Evaluate the Efficacy and Safety of Eculizumab in Patients with Guillain-Barré Syndrome (GBS): Protocol of Japanese Eculizumab Trial for GBS (JET-GBS).

BACKGROUND: Guillain-Barré syndrome (GBS) is an immune-mediated neuropathy that causes acute flaccid paralysis. Immunoglobulin and plasma exchange are established treatments for GBS; however, a substantial number of patients, particularly those with severe disease, have poor recovery and residual deficits. Recent studies suggest that complement activation plays a pivotal role in GBS-associated axonal degeneration, and eculizumab is a humanized monoclonal antibody that specifically binds to complement component 5 and potently inhibits complement activation. OBJECTIVE: This clinical trial aims to evaluate the efficacy and safety of eculizumab, a humanized monoclonal antibody directed against complement component 5, for treatment of GBS. METHODS: The Japanese Eculizumab Trial for GBS (JET-GBS) is a prospective, multicenter, placebo-controlled, double-blind, randomized phase II study conducted at 13 tertiary neurology centers and is funded by the Japan Agency for Medical Research and Development. A total of 33 GBS patients unable to walk independently within 2 weeks from symptom onset (Hughes functional grade 3-5) were randomized at a 2:1 ratio to receive either intravenous eculizumab (900 mg/day) or placebo once weekly for 4 weeks, followed by 20 weeks of follow-up. The primary endpoint for efficacy is the proportion of patients who regain their ability to walk without aid at 4 weeks after the first dose of the study treatment, while primary safety outcomes are the incidence of adverse events and serious adverse events during the trial. RESULTS: Enrollment for the trial began in August 2015. This trial is still ongoing. All participants have been enrolled, and follow-up will be completed in October 2016. CONCLUSIONS: This study is the first to investigate the efficacy and safety of eculizumab for GBS. In case of a positive result, we will plan a phase III trial to investigate this issue in a larger number of patients. CLINICALTRIAL: UMIN Clinical Trials Registry UMIN 000018171; https:/upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function= brows&action=brows&type=summary&language=J&recptno=R000020978 (Archived by WebCite at http://www.webcitation.org/ 6lTiG8ltG). Clinical Trials.gov NCT02493725; https://clinicaltrials.gov/ct2/show/NCT02493725 (Archived by WebCite at http://www.webcitation.org/6lVJZXKSL).

Recurrent Guillain-Barré syndrome presenting stereotypic manifestations, positive antiganglioside antibodies, and rapid recovery.

OBJECTIVE: Recurrent Guillain-Barré syndrome (rGBS) has been described as a rare entity with distinct characteristics. However, little is known about rGBS in Asian group. The aim of this study was to identify the incidence and clinical course of rGBS, and to determine its clinical/pathophysiological implications. METHODS: The consecutive data of 117 GBS patients were retrieved from a single university-based hospital in Korea and analyzed in terms of clinical, serological, electrophysiological aspects. RESULTS: A thorough review revealed that three (2.6%) of the enrolled patients had experienced more than two definite recurrent attacks of GBS. Interestingly, all three cases exhibited clinically stereotypical features, serum antiganglioside antibodies, and rapid recovery after intravenous immunoglobulin treatment. Clinical, serological, and electrophysiological features of rGBS cases were described in detail. CONCLUSION: The stereotypic presentation of each attack in this variant suggests the importance of both host and genetic factors for the clinical manifestations. In addition, the simultaneous presence of serum antiganglioside antibodies and rapid recovery implicate reversible nerve conduction failure as the mechanism of rGBS. These features are different from typical monophasic GBS and acute onset of chronic inflammatory demyelinating polyneuropathy.

Spinal nerve involvement in early Guillain-Barré syndrome: a clinico-electrophysiological, ultrasonographic and pathological study.

OBJECTIVE: Although prevailing spinal nerve involvement has been recognized in a few detailed Guillain-Barré syndrome (GBS) autopsy reports, imaging studies addressing this question in cervical nerves are lacking. METHODS: We describe clinical, electrophysiological, ultrasonographic (US) and pathological findings in six consecutive early GBS patients, evaluated within 10 days of onset. RESULTS: Patients' ages ranged from 37 to 80 years. Five patients required mechanical ventilation, two of them having died 9 and 28 days after onset. Upper- and lower-limb nerve US showed abnormal findings in just 8.8% of scanned peripheral nerves. In comparison with 46 aged-matched control subjects, US of the fifth to seventh cervical nerves showed changes in four cases, which consisted of significant nerve enlargement, blurred boundaries of the corresponding ventral rami, or both. Autopsy study in one case demonstrated that pathology, consisting of demyelination and endoneurial inflammatory oedema, mainly involved cervical and lumbar nerves. CONCLUSIONS: In early GBS inflammatory oedema of spinal nerves is a pathogenically relevant feature to understanding the mechanism of ascending paralysis, particularly when conventional electrophysiological studies are normal or not diagnostic. SIGNIFICANCE: Findings advocate the use of cervical nerve US in early GBS.