Hiroyuki Murai's research while affiliated with Narita Hospital and other places

Publications (212)

Article
Introduction: The management of myasthenia gravis (MG) has been improved due to immunotherapy advances, but 20% of individuals with MG are refractory to the conventional therapy, and the need for novel biological drugs remains. Area covered: The Japanese clinical guidelines for MG published in May 2022 include the concept that treatment is often...
Article
The primary purpose of the Japanese myasthenia gravis registry (JAMG‐R) has been to research and promote high‐quality medical care for MG patients in Japan. We reviewed the findings of surveys performed by JAMG‐R over an approximately 10‐year period. The first goal for favorable quality of life (QOL) is a status of minimal manifestations (MM) or be...
Article
Generalised myasthenia gravis (gMG), a rare, chronic, autoimmune disease affecting the neuromuscular junction, results in life-debilitating fatigable muscle weakness. More effective, safer and convenient therapeutic strategies for a broad patient population with seropositive gMG are needed. Interleukin 6 (IL-6) has been associated with disease acti...
Article
Full-text available
Objective To study the updated prevalence and clinical features of myasthenia gravis (MG) in Japan during 2017. Methods We sent survey sheets to the randomly selected medical departments (number = 7,545). First, we asked the number of MG patients who visited medical departments from January 1, 2017, to December 31, 2017. Then, we sent the second s...
Article
Full-text available
Background There was no nationwide epidemiological study of Lambert-Eaton myasthenic syndrome (LEMS) in Japan; therefore, we conducted a nationwide survey. Methods For the first survey, we sent survey sheets to randomly selected medical departments (n=7545) to obtain the number of LEMS who visited medical departments between 1 January 2017 and 31...
Article
Eculizumab, a terminal complement protein C5 inhibitor, is approved in Japan for treatment of patients with anti‐acetylcholine receptor antibody‐positive (AChR Ab+) generalized myasthenia gravis (gMG) that is difficult to control with plasmapheresis or high‐dose intravenous immunoglobulin therapy. This analysis of mandatory post‐marketing surveilla...
Article
Myasthenia gravis and Lambert-Eaton myasthenic syndrome are antibody-mediated autoimmune diseases of the neuromuscular junction that usually present with weakness in ocular muscles and in proximal muscles of the limb and trunk. Prognosis regarding muscle strength, functional abilities, quality of life, and survival is generally good. However, some...
Article
Full-text available
Antiepileptic medications (ASMs) are withdrawn at the epilepsy monitoring unit to facilitate seizure recordings. The effect of rapid tapering of ASMs on the length of hospital stay has not been well documented. We compared the mean length of hospital stay between patients who underwent acute ASM withdrawal and slow dose tapering during long-term vi...
Article
Full-text available
Objective To determine the characteristics of olfactory dysfunction in patients with temporal lobe epilepsy (TLE). Methods Odor identification was assessed using the odor stick identification test for Japanese (OSIT-J, full score 12 points) in 65 patients with TLE and in 74 controls. Results The mean OSIT-J score was significantly lower in patien...
Article
Background and aims Efgartigimod, a human IgG1 antibody Fc-fragment, blocks the neonatal Fc receptor, which decreases recycling of IgG and reduces pathogenic autoantibody levels. In a phase 2 study, it demonstrated efficacy and was well tolerated in patients with generalized myasthenia gravis (gMG), an IgG antibody-mediated disease. Methods ADAPT...
Article
Introduction/Aims Individuals with refractory generalized myasthenia gravis (gMG) who have a history of rituximab use and experience persistent symptoms represent a population with unmet treatment needs. The aim of this analysis was to evaluate the efficacy and safety of eculizumab in patients with refractory anti-acetylcholine receptor antibody-po...
Article
Introduction. There have been few reports on the ictal video electroencephalogram (VEEG) of amnesic attacks in patients with transient epileptic amnesia (TEA). TEA attacks often occur on waking, but the reason remains unclear. Results. A 65-year-old man had a three-month history of recurrent episodes of antero- and retrograde amnesia. The episodes...
Article
Full-text available
Introduction Myasthenia gravis (MG) is a rare, chronic, autoimmune disease, mediated by immunoglobulin G antibodies, which causes debilitating muscle weakness. As with most rare diseases, there is little patient-reported data with which to understand and address patient needs. This study explores the impact of MG in the real world from the patient...
Article
Background There is an unmet need for treatment options for generalised myasthenia gravis that are effective, targeted, well tolerated, and can be used in a broad population of patients. We aimed to assess the safety and efficacy of efgartigimod (ARGX-113), a human IgG1 antibody Fc fragment engineered to reduce pathogenic IgG autoantibody levels, i...
Article
Full-text available
Objective Periprocedural thromboembolic events are a serious complication associated with coil embolization of unruptured intracranial aneurysms. However, no established clinical rule for predicting thromboembolic events exists. This study aimed to clarify the significance of adding preoperative clopidogrel response value to clinical factors when p...
Article
Full-text available
Introduction Generalized myasthenia gravis (gMG) is an autoimmune disorder in which pathogenic autoantibodies damage the neuromuscular junction, causing disabling or life-threatening muscle weakness. Most treatments nonspecifically inhibit aspects of the immune system, do not directly address the causal mechanisms of tissue damage, and often have s...
Article
Full-text available
Background Eculizumab, a humanized monoclonal antibody targeted to terminal complement protein C5, is approved in Japan for treatment of patients with anti-acetylcholine receptor antibody-positive (AChR+) generalized myasthenia gravis (gMG) whose symptoms are difficult to control with high-dose intravenous immunoglobulin (IVIg) therapy or plasmaphe...
Article
Full-text available
Myasthenia gravis (MG) is characterized by muscle weakness and fatigue caused by the presence of autoantibodies against the acetylcholine receptor (AChR) or the muscle‐specific tyrosine kinase (MuSK). Activated T, B and plasma cells, as well as cytokines, play important roles in the production of pathogenic autoantibodies and the induction of infla...
Article
Full-text available
Objective: To update the 2016 formal consensus-based guidance for the management of myasthenia gravis (MG) based on the latest evidence in the literature. Methods: In October 2013, the Myasthenia Gravis Foundation of America appointed a Task Force to develop treatment guidance for MG, and a panel of 15 international experts was convened. The RAN...
Article
A new version of the Japanese clinical guidelines for myasthenia gravis is under development. The current version was published in 2014, in which the top priority in treatment was to maintain patients’ health‐related quality of life. The treatment goal was to achieve a post‐intervention status of minimal manifestations or better (according to the M...
Article
Objective To clinically diagnose MM2-cortical (MM2C) and MM2-thalamic (MM2T)-type sporadic Creutzfeldt-Jakob disease (sCJD) at early stage with high sensitivity and specificity. Methods We reviewed the results of Creutzfeldt-Jakob disease Surveillance Study in Japan between April 1999 and September 2019, which included 254 patients with pathologic...
Article
Anti‐striational antibodies (StrAbs) have been described as serum immunoglobulins that react with cross‐striations of skeletal muscle in patients with myasthenia gravis (MG). StrAbs were expected to be useful biomarkers of MG, however, because of their low specificity, the diagnostic utility of StrAbs has been limited. The main autoantigens of StrA...
Article
Full-text available
Treatment with oral corticosteroids at high doses with an escalation and de-escalation schedule is effective against myasthena gravis (MG). In fact, the use of corticosteroids has led to a reduction in mortality to below 10% after the 1960s. However, long-term use of oral steroids above a certain dosage level is known to cause a number of problems....
Article
Purpose To elucidate the extension patterns of the hyperintense areas on diffusion-weighted magnetic resonance imaging (DW-MRI) in patients with dura mater graft-associated Creutzfeldt-Jakob disease (dCJD). Methods We collected the DW-MRI of dCJD cases identified by the CJD Surveillance Committee in Japan, between April 1999 and February 2018. The...
Article
Our multicenter studies have repeatedly demonstrated that disease severity and oral steroid dose are major independent factors negatively impacting health‐related quality of life (QOL) in patients with myasthenia gravis. Even if pharmacologic remission is achieved, QOL is low in patients taking oral prednisolone >10 mg/day. Disease severity tends t...
Article
Full-text available
Objective To assess whether eculizumab, a terminal complement inhibitor, improves patient‐ and physician‐reported outcomes (evaluated using the myasthenia gravis activities of daily living profile and the quantitative myasthenia gravis scale, respectively) in patients with refractory anti‐acetylcholine receptor antibody‐positive generalized myasthe...
Article
Full-text available
We previously reported a phenotype of Creutzfeldt-Jakob disease (CJD), CJD-MMiK, that could help identify iatrogenic CJD. To find cases mimicking CJD-MMiK, we investigated clinical features and pathology of 1,155 patients with diagnosed sporadic CJD or unclassified CJD with and without history of neurosurgery. Patients with history of neurosurgery...
Article
Full-text available
Background In the phase III eculizumab for refractory generalized myasthenia gravis REGAIN study [ClinicalTrials.gov identifier: NCT01997229] and its open-label extension (OLE) [ClinicalTrials.gov identifier: NCT02301624], patients with treatment-refractory antiacetylcholine receptor antibody-positive generalized myasthenia gravis had clinically me...
Article
Full-text available
Background Eculizumab is a humanized monoclonal antibody that targets complement protein C5 and inhibits terminal complement-mediated damage at the neuromuscular junction. Recently, the REGAIN study showed that eculizumab was effective and well tolerated in patients with anti-acetylcholine receptor antibody-positive refractory generalized myastheni...
Article
Full-text available
The terminal complement inhibitor eculizumab was shown to improve myasthenia gravis-related symptoms in the 26-week, phase 3, randomized, double-blind, placebo-controlled REGAIN study (NCT01997229). In this 52-week sub-analysis of the open-label extension of REGAIN (NCT02301624), eculizumab's efficacy and safety were assessed in 11 Japanese and 88...
Article
In this report, we describe a case of a 58‐year‐old man with limbic encephalitis associated with anti‐voltage‐gated potassium channel complex antibodies (anti‐VGKCC‐ab). He exhibited clinical and diffusion‐weighted imaging (DWI) findings suspicious for Creutzfeldt‐Jakob disease (CJD). Unlike similar reported cases, DWI findings paralleled with neur...
Article
Full-text available
Introduction Eculizumab is effective and well tolerated in patients with anti‐acetylcholine receptor antibody‐positive refractory generalized myasthenia gravis (gMG; REGAIN; NCT01997229). We report an interim analysis of an open‐label extension of REGAIN evaluating eculizumab's long‐term safety and efficacy. Methods 117 patients received eculizuma...
Article
Full-text available
Objectives To compare the burden of illness for refractory and non‐refractory myasthenia gravis (MG) in Japanese patients. Methods Adults in a large Japanese health insurance claims database (1 September 2008 to 31 October 2016) were included in this retrospective, observational study if they had: at least two separate claims coded as MG by a neur...
Article
Objectives Most patients with myasthenia gravis (MG) undergo thoracic imaging at initial diagnosis. However, the follow‐up protocol is unclear. The objective of the present study was to clarify the follow‐up status and main findings of thoracic imaging in patients with MG. Methods A total of 649 patients with disease duration ≥1 year were included...
Article
According to the 2014 Japanese clinical guidelines for myasthenia gravis, the most important priority in treatment is maintaining patients’ health-related quality of life. Therefore, the initial treatment goal is defined as maintaining a postintervention status of minimal manifestations or better (according to the Myasthenia Gravis Foundation of Am...
Article
Full-text available
Objective We examined the correlation between the dosing regimen of oral prednisolone (PSL) and the achievement of minimal manifestation status or better on PSL ≤5 mg/day lasting >6 months (the treatment target) in patients with generalised myasthenia gravis (MG). Methods We classified 590 patients with generalised MG into high-dose (n=237), inter...
Article
Background: Complement is likely to have a role in refractory generalised myasthenia gravis, but no approved therapies specifically target this system. Results from a phase 2 study suggested that eculizumab, a terminal complement inhibitor, produced clinically meaningful improvements in patients with anti-acetylcholine receptor antibody-positive r...
Article
Full-text available
Documentation of the current status of specialty training to become a neurologist in Japan would represent an important basis for constructing better neurology training program in the planned reform of the specialty training system in Japan. The committee for future neurology specialty system of Japanese Society of Neurology (JSN) conducted a quest...
Article
Background End-diastolic ratio, calculated by the side-to-side ratio of end-diastolic flow velocities of the common carotid arteries, is an indicator for large artery intracranial occlusive disease. However, the diagnostic ability of end-diastolic ratios derived from different measurement conditions is unclear. Methods End-diastolic ratios were me...
Article
The electroencephalographic finding of periodic synchronous discharges (PSDs) is a basic clue for the diagnosis of Creutzfeldt-Jacob disease (CJD). We proposed grading of PSDs. We defined grade A as typical PSDs, grade B as PSDs of relatively longer periodic intervals, grade C as PSDs of relatively rare appearance, grade D as PSDs of rudimentary ap...
Article
Full-text available
Apomorphine (APO) promotes intraneuronal amyloid-β (Aβ) degradation and improves memory function in an Alzheimer's disease (AD) model, 3xTg-AD mice. Since insulin resistance is increased in AD neurons, we investigated the effects of APO on brain insulin resistance in 3xTg-AD mice at early and late stages. After 1-month subcutaneous injection of Apo...
Article
Full-text available
Objectives To clarify the social disadvantages associated with myasthenia gravis (MG) and examine associations with its disease and treatment. Design Cross-sectional study. Setting and participants We evaluated 917 consecutive cases of established MG seen at 13 neurological centres in Japan over a short duration. Outcome measures All patients co...
Article
Full-text available
Background We have previously reported using two-step cluster analysis to classify myasthenia gravis (MG) patients into the following five subtypes: ocular MG; thymoma-associated MG; MG with thymic hyperplasia; anti-acetylcholine receptor antibody (AChR-Ab)-negative MG; and AChR-Ab-positive MG without thymic abnormalities. The objectives of the pre...
Article
Introduction: The MG-QOL15 is a validated, health-related quality of life (HRQOL) measure for myasthenia gravis (MG). Widespread use of the scale gave us the opportunity to further analyze its clinimetric properties. Methods: We first performed Rasch analysis on >1,300 15-item Myasthenia Gravis Quality of Life scale (MG-QOL15) completed surveys. Re...
Article
Full-text available
A 37-old-male with a history of early childhood mental retardation was admitted to our hospital. He experienced recurrent syncopes at 23 years old, and at age 35 gait disturbance and hearing impairment developed gradually and worsened over time. His grandparents were in a consanguineous marriage. He was of short stature and absent of tendon xanthom...
Article
A 34-year-old man presented with an acute onset of upbeat nystagmus, slurred speech, and limb and truncal ataxias. The patient had a history of limb ataxia and gait disturbance previously treated as brainstem encephalitis with corticosteroids 3 years previously. Brain magnetic resonance imaging showed pontine developmental venous anomaly (DVA) and...
Article
Full-text available
Purpose: We sought to clarify the effects of early fast-acting treatment (EFT) strategies on the time course for achieving the treatment target in generalized myasthenia gravis (MG). Methods: This retrospective study of 923 consecutive MG patients analyzed 688 generalized MG patients who had received immunotherapy during the disease course. The...
Article
Background: We aimed to determine the predictive factors for excellent or extremely poor functional outcome in patients with first-ever atrial fibrillation (AF)-related cardioembolic stroke. Methods: Retrospective observational study from a database. Patients with AF-related cardioembolic stroke with a premorbid modified Rankin Scale (mRS) score...
Article
We describe a 69-year-old woman with dermatomyositis who presented with asymmetric peripheral neuritis. The patient first developed dermatomyositis at 39 years-of-age; her symptoms improved several years later with oral prednisolone treatment. A year and a half before admission to our hospital, she developed a sensory disturbance in her feet that g...
Article
Full-text available
Objective: To develop formal consensus-based guidance for the management of myasthenia gravis (MG). Methods: In October 2013, the Myasthenia Gravis Foundation of America appointed a Task Force to develop treatment guidance for MG, and a panel of 15 international experts was convened. The RAND/UCLA appropriateness methodology was used to develop...
Article
Aim: Atrial fibrillation (AF)-related cardioembolic stroke is a serious problem in the aging society. The present study examined the clinical characteristics and outcomes of AF-related cardioembolic stroke in patients aged ≥80 years. Methods: Between September 2011 and April 2014, consecutive patients with ischemic stroke and AF were retrospecti...
Article
Introduction: The MG-QOL15 is a validated, HRQOL measure for myasthenia gravis (MG). Widespread use of the scale gave us the opportunity to further analyze its clinimetric properties. Methods: We first performed Rasch analysis on >1300 MG-QOL15 completed surveys. Results were discussed during a conference call with specialists and biostatisticia...
Article
Full-text available
Objectives: Studies of longitudinally extensive spinal cord lesions (LESCLs) in neuromyelitis optica (NMO) have focused on gray matter, where the relevant antigen, aquaporin-4 (AQP4), is abundant. Because spinal white matter pathology in NMO is not well characterized, we aimed to clarify spinal white matter pathology of LESCLs in NMO. Methods: W...
Article
Full-text available
We present the first case of Morvan’s syndrome (MoS) and myasthenia gravis (MG) related to familial Mediterranean fever (FMF) gene mutations. Case presentation A 40-year-old woman with a 1-year history of bilateral ptosis and limb muscle weakness presented to our hospital. She also had memory impairment, insomnia, hyperhidrosis, and muscle twitches...
Article
Full-text available
A 24-year-old man was referred to our hospital emergency department due to a sudden onset of convulsions after drinking. On arrival he presented status epilepticus and was managed by artificial ventilation. He had no brainstem signs or meningeal irritation. Head MRI showed an old infarction-like lesion in the left occipital lobe, but no abnormal si...
Article
Full-text available
We report the case of a 17-year-old woman with paroxysmal sympathetic storm (PSS), which was successfully treated with clonidine hydrochloride. The patient was hospitalized for acute disseminated encephalomyelitis in June 2006. Dysphagia led to severe aspiration pneumonia in September 2006, and she suffered cardiopulmonary arrest. She survived but...
Article
Full-text available
Background: No large-scale studies have compared the efficacy of intravenous methylprednisolone pulse therapy (IVMP) for multiple sclerosis (MS) and neuromyelitis optica (NMO). Objective: To explain differences in treatment responses of MS and NMO patients to IVMP. Methods: Changes in neurological symptoms/signs and Expanded Disability Status...