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Myasthenia gravis (MG) is an autoimmune disease caused by antibodies against the acetylcholine receptor (AChR), muscle-specific kinase (MuSK) or other AChR-related proteins in the postsynaptic muscle membrane. Localized or general muscle weakness is the predominant symptom and is induced by the antibodies. Patients are grouped according to the presence of antibodies, symptoms, age at onset and thymus pathology. Diagnosis is straightforward in most patients with typical symptoms and a positive antibody test, although a detailed clinical and neurophysiological examination is important in antibody-negative patients. MG therapy should be ambitious and aim for clinical remission or only mild symptoms with near-normal function and quality of life. Treatment should be based on MG subgroup and includes symptomatic treatment using acetylcholinesterase inhibitors, thymectomy and immunotherapy. Intravenous immunoglobulin and plasma exchange are fast-acting treatments used for disease exacerbations, and intensive care is necessary during exacerbations with respiratory failure. Comorbidity is frequent, particularly in elderly patients. Active physical training should be encouraged.

Introduction: Herein we report our experience with the repetitive nerve stimulation (RNS) test in myasthenia gravis (MG) crisis., Methods: The various parameters of the RNS tests in 26 patients with MG crisis were analyzed., Results: In 18 (69%) patients, MG crisis is the first manifestation of MG. RNS tests were abnormal in 24 (92%) patients by decrement at low-rate stimulation in any of 4 tested muscles. Three patterns of abnormality were found: MG pattern (decrement at low-rate stimulation) in 23 patients; Lambert-Eaton myasthenic syndrome pattern in 1 patient; and cholinergic crisis pattern in 1 patient., Discussion: During MG crisis, the RNS test can serve as a rapid and sensitive diagnostic tool for MG in a majority of patients. Muscle Nerve 59:544-544, 2019., (© 2018 Wiley Periodicals, Inc.)

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder that can affect the ocular, bulbar, neck, proximal limb, and respiratory muscles. This case study presents two similar individuals diagnosed with MG that presented with varying symptomatology and also with a different response to therapy. These two patients represent a unique patient group that represents only 10% of patients diagnosed with MG.

Introduction: Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Approximately 10%-15% of MG patients have juvenile (<18 years of age) onset. We aimed to assess the clinical course, outcome, and subjectively perceived health status of a cohort of juvenile MG patients., Methods: This was a retrospective analysis of medical records of 101 patients followed by a cross-sectional questionnaire study., Results: The mean age of patients was 12.8 years at onset and 13.7 years at diagnosis. Ninety percent of the patients were seropositive. Over 40% of the patients were treated with immunosuppression and over 80% underwent thymectomy. The mean Myathenia Gravis Activities of Daily Living (MG-ADL) scale score was 2.48. At last follow-up, 30.9% of patients were in complete, stable remission; 77.8% perceived their health as good., Discussion: The treatment outcome for juvenile MG is favorable, with a marked reduction of symptoms and good day-to-day activity achieved for most patients. Muscle Nerve 59:549-549, 2019., (© 2019 Wiley Periodicals, Inc.)

In myasthenia gravis autoantibodies target components of the neuromuscular junction causing variable degrees of weakness. In most cases, autoantibodies trigger complement-mediated endplate damage and extraocular muscles may be most susceptible. A proportion of MG cases develop treatment-resistant ophthalmoplegia. We reviewed publications spanning 65 years reporting the histopathological findings in the muscles and extraocular muscles of myasthenic patients to determine whether pathological changes in extraocular muscles differ from non-ocular muscles. As extraocular muscles represent a unique muscle allotype we also compared their histopathology in myasthenia to those in strabismus. We found that in myasthenia gravis, the non-ocular muscles frequently demonstrate neurogenic changes regardless of myasthenic serotype. Mitochondrial stress/damage was also frequent in myasthenic muscles and possibly more evident in muscle-specific kinase antibody-positive MG. Although myasthenia-associated paralysed extraocular muscles demonstrated prominent fibro-fatty replacement and mitochondrial alterations, these features appeared commonly in paralysed extraocular muscles of any cause. We postulate that extraocular muscles may be more susceptible than limb muscles to poor contractility as a consequence of myasthenia, resulting in a cascade of atrophy signaling pathways and altered mitochondrial homeostasis which contribute to the tipping point in developing treatment-resistant myasthenic ophthalmoplegia. Early strategies to improve force generation in extraocular muscles are critical., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Introduction: We translated the myasthenia gravis (MG)-specific activities of daily living (MG-ADL) scale into Arabic (MG-ADL-A) and assessed its psychometric properties., Methods: We assessed reliability using Cronbach's α, reproducibility using the intraclass correlation coefficient, and validity using Spearman's correlations with MG composite (MGC) score, MG-specific manual muscle test (MG-MMT), and MG quality-of-life revised Arabic version (MGQOL15R-A). Differences in MG-ADL-A scores among patients with different disease severity were evaluated by using the Kruskal-Wallis test. Sensitivity to change was examined by using the Wilcoxon signed-rank test., Results: We recruited 87 patients. The mean MG-ADL-A score was 3.38 ± 3.38 (α = 0.77, ICC = 0.99). The correlation coefficients between the MG-ADL-A and MGQOL15R-A, MGC, and MG-MMT were 0.63, 0.74, and 0.61, respectively (P < 0.001). The MG-ADL-A discriminated between different severity groups and was responsive to clinical improvement at follow-up., Discussion: The MG-ADL-A has rigorous psychometric properties and can be used with Arabic-speaking patients with MG. Muscle Nerve 59:583-583, 2019., (© 2019 Wiley Periodicals, Inc.)

Myasthenia gravis (MG) is an autoimmune disease where antibodies attack the presynaptic terminals at the neuromuscular junction causing progressive weakness. Associated with thymomas, resection can improve symptoms. A 29-year-old woman with MG who underwent two previous thymectomies, at ages 11 and 15 presented 14 years later with recurrent MG symptoms and an anterior mediastinal mass. Robotic-assisted thoracoscopic excision of the mediastinal mass was performed without complications. She recovered well and had improvement of her MG symptoms. Thymectomy can significantly improve symptoms in MG even for patients who do not have a thymoma. Reports of distant benign thymoma recurrence are rare. MG patients require continued monitoring and vigilance, even after thymectomy. Benign thymomas can recur even after significant time intervals, and utilisation of the robotic platform for recurrent thymoma excision is safe, even following two sternotomies. Patient symptoms improve with redo thymectomy., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To investigate the correlations between the 6-minute walk test and disease severity, pulmonary functions, and respiratory muscle performance in patients with generalized myasthenia gravis (MG) and to determine whether MG disease severity, pulmonary functions, and respiratory muscle performance contribute to 6-minute walk test distance in generalized MG., Methods: This cross-sectional trial was conducted at Hacettepe University in Ankara, Turkey. The study was carried out from February to August 2017. Twenty-eight class II-III MG patients participated in the study. Patients` disease severity was determined with the Myasthenia gravis composite scale. All participants underwent the 6-minute walk test, pulmonary function tests, and respiratory muscle strength and endurance assessment., Results: Approximately 40% of patients` expiratory muscle strength were under the lower limit of normal. Multiple linear regression analysis revealed that the percentage of predicted expiratory muscle strength that patients reached were significant and independent predictor of percentage of 6-minute walk test distance that patients reached according to reference values (R2=0.493, F [1-27]=25.275, p less than 0.001)., Conclusion: Expiratory muscle strength is a significant determinant of functional exercise performance in generalized MG with mild or moderate weakness affecting muscles other than the ocular muscles.

The accuracy of the ice-pack test for diagnosing myasthenia gravis (MG) has been reported to be excellent, however, the sensitivity is low in patients with mild ptosis which is common in Asians who have absent or low double eyelid folds. Herein, we performed the ice-pack test after sustained upgaze and tested its validity for diagnosing MG. The study included 30 newly diagnosed MG patients with ptosis (median age 47 years, range 2-87 years) and 30 controls with ptosis other than MG (median age 58 years, range 5-83 years). All MG patients initially presented with ptosis and/or diplopia; 26 patients had purely ocular MG while 4 patients progressed to generalized MG. All patients performed the new ice-pack test after sustained upgaze for 2 min. The ice-pack test was judged positive if there was an improvement of at least 2 mm of margin reflex distance compared to the level of ptosis before (conventional ice-pack test) or after (new ice-pack test) sustained upgaze. Subgroup analysis was performed according to the level of ptosis. The conventional test showed 43.3% sensitivity and 100% specificity for diagnosing MG, while the new ice-pack test achieved 73.3% sensitivity and 96.7% specificity, respectively. In patients with mild ptosis, the sensitivity and specificity for diagnosing MG were 27.8% and 100% by the conventional test, and 72.2% and 96.7% by the new ice-pack test, respectively. The new ice-pack test combined with sustained upgaze was more sensitive for diagnosing MG, particularly in patients with mild ptosis which is common in Asians., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Despite its potentially significant impact on disease outcome, peripheral nervous system involvement in systemic lupus erythematosus has received little attention., Objective: The objective of this study was to assess the prevalence and clinical features of peripheral nervous system involvement in a large cohort of systemic lupus erythematosus patients., Methods: The records of systemic lupus erythematosus patients examined at two tertiary referral centres over a period of 14 years (from 2000 to 2014) were analyzed. Peripheral nervous system events were ascertained according to the 1999 American College of Rheumatology case definitions and by using an attribution algorithm for neuropsychiatric events. Prevalence of peripheral nervous system in systemic lupus erythematosus and demographic, clinical and laboratory features were assessed. Patients with peripheral nervous system events were compared with a control group of systemic lupus erythematosus patients without peripheral nervous system involvement., Results: In a retrospective cohort of 1224 patients, the overall prevalence of peripheral nervous system involvement was 6.9% (85 patients, 95% confidence interval 0.06-0.08), with 68% of peripheral nervous system events attributable to systemic lupus erythematosus. Polyneuropathy was the most common manifestation observed (38 events, 39.2%), followed by cranial neuropathy in 30 cases (30.9%) and 12 cases of single (12.4%) or multiple (eight events, 8.2%) mononeuritis. The average age of systemic lupus erythematosus onset was significantly higher in patients with peripheral nervous system events than in controls (mean ± standard deviation: 45.9 ± 14.8 vs. 37.1 ± 14.0) and they were more likely to have higher SLEDAI-2K and SLICC/ACR Damage Index scores, as well as hypertension and livedo reticularis. A subgroup analysis of events deemed to be systemic lupus erythematosus-related provided similar results., Conclusion: Peripheral nervous system manifestations are a potential complication of systemic lupus erythematosus. Careful neurological assessment should therefore be included in the diagnostic workup of patients with systemic lupus erythematosus, especially in those with later onset and greater damage and disease activity.

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease involving both upper and lower motor neurons with no effective cure. Electrophysiological studies have found decremental responses during low-frequency repetitive nerve stimulation (RNS) except for diffused neurogenic activities. However, the difference between ALS and generalized myasthenia gravis (GMG) in terms of waveform features is unclear. In the current study, we explored the variation trend of the amplitudes curve between ALS and GMG with low-frequency, positive RNS, and the possible mechanism is discussed preliminarily., Methods: A total of 85 ALS patients and 41 GMG patients were recruited. All patients were from Peking Union Medical College Hospital (PUMCH) between July 1, 2012 and February 28, 2015. RNS study included ulnar nerve, accessory nerve and facial nerve at 3 Hz and 5 Hz stimulation. The percentage reduction in the amplitude of the fourth or fifth wave from the first wave was calculated and compared with the normal values of our hospital. A 15% decrease in amplitude is defined as a decrease in amplitude., Results: The decremental response at low-frequency RNS showed the abnormal rate of RNS decline was 54.1% (46/85) in the ALS group, and the results of different nerves were 54.1% (46/85) of the accessory nerve, 8.2% (7/85) of the ulnar nerve and 0% (0/85) of the facial nerve stimulation, respectively. In the GMG group, the abnormal rate of RNS decline was 100% (41/41) at low-frequency RNS of accessory nerves. However, there was a significant difference between the 2 groups in the amplitude after the sixth wave., Conclusions: Both groups of patients are able to show a decreasing amplitude of low-frequency stimulation RNS, but the recovery trend after the sixth wave has significant variation. It implies the different pathogenesis of NMJ dysfunction of these 2 diseases.

Background: Myasthenia gravis (MG) is an autoimmune disease. Dysarthria, dysphagia, and difficulty swallowing as exclusive initial and primary complaints in MG (laryngeal MG) are rare and seldom reported., Methods: Here we review and analyze the largest series of laryngeal MG patients., Results: A total of 30 patients with laryngeal MG as primary manifestation were found in 20 case reports/series. Dysarthria was the most frequent primary symptom (14/30), followed by dysphagia (11/30), slurred speech (4/30) and dysphonia (1/30). Sixty-three percent visited the otolaryngology department first. Only 23.33% of patients were diagnosed with MG at the first clinic visit. Forty-five percent laryngeal MG patients were acetylcholine receptor (AChR) antibody positive, 52.9% showed decremental response in the repetitive nerve stimulation (RNS) test, and 92.6% were positive in the neostigmine/edrophonium test. Fluctuating weakness was examined in 16 of 30 patients and observed in 14/16 patients., Conclusion: Laryngeal MG is a rare and possibly under-diagnosed condition. The patients can present with dysarthria, dysphagia, or difficulty swallowing. Fluctuation in severity of disease by neostigmine/edrophonium test is a typical feature for MG patients. AChR antibody and RNS tests should be included to evaluate the pathologic changes in the neuromuscular junction., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objectives: Myasthenia gravis (MG) is an autoimmune disease associated with antibodies against the nicotinic muscle acetylcholine receptor (AChR) at the neuromuscular junction. Dysautonomia has been previously described in MG. Electrochemical skin conductance (ESC), assessed by Sudoscan ® , is a non-invasive method that allows evaluation of sudomotor function. Since sweat glands are innervated by sudomotor, postganglionic, cholinergic sympathetic C-fibers, we hypothesized that ESC could be a reliable method for assessing autonomic dysfunction in MG., Methods: ESC measurements were prospectively assessed in patients with generalized MG and in healthy controls. Patients with diabetes mellitus, anticholinergic medication or electrophysiological findings of peripheral neuropathy were excluded. Data regarding demographic and disease features were collected. Presence of autonomic symptoms in patients with MG was assessed by Compass-31. For statistical analysis we performed student t-test and Chi 2 test for comparison between both groups., Results: We included 24 patients (mean age of 46.4±10.6, 75% women, mean disease duration 12.5 years, 62.5% positive for AChR antibodies) and 37 controls. We found no difference in either foot (P=0.13) or hand (P=0.83) ESC measurements between patients and controls, even after correcting for age., Conclusion: We could not prove the presence of autonomic sympathetic dysfunction in our cohort of MG patients when assessed by Sudoscan ® . In addition, Compass-31 was not a useful questionnaire in this clinical context., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Introduction: We sought to evaluate the test-retest reliability and construct validity of the 6- and 2-minute walk tests (6mWT and 2mWT, respectively) in patients with myasthenia gravis (MG)., Methods: Thirty-one patients with generalized MG were enrolled in this study. The 6mWT, 2mWT, MG-specific quality of life questionnaire Turkish version (MG-QoL15T), quantitative myasthenia gravis test (QMG), and pulmonary function tests were administered., Results: The intraclass correlation coefficients of 2mWT and 6mWT were 0.894 and 0.932, respectively. The 6mWT and 2mWT had moderate correlations with forced vital capacity, maximal inspiratory pressure, QMG score, and MG-QoL15T score (ρ for 6mWT: 0.579, 0.539, -0.572, and -0.474; ρ for 2mWT: 0.460, 0.446, -0.532, -0.457). Both tests had similar performances for predicting disease severity (area under the curve = 0.761 for 6mWT and 0.759 for 2mWT)., Discussion: The 6mWT and 2mWT have excellent test-retest reliability as well as moderate construct validity for the evaluation of functional exercise capacity patients with MG. Muscle Nerve 59:208-212, 2019., (© 2018 Wiley Periodicals, Inc.)

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disease in which antibodies against the post-nicotinic acetylcholine receptor at the neuromuscular junction develop. Although the exact cause of MG remains unknown, the thymus is a common factor in many cases. Patients with underlying junctional disease, such as MG, have greater anesthesia-related risks because of their known predisposition toward prolonged muscle weakness. Medications given in the perioperative period, such as anesthetic agents, antibiotics, cardiovascular drugs, and corticosteroids, affect neuromuscular transmission that contributes to muscle weakness. Judicious use of neuromuscular blocking agents for patients with MG must be considered. This patient population is at high risk for respiratory failure, and therefore must be carefully assessed throughout the perioperative period to ensure that a regular spontaneous respiratory pattern is sufficient to provide adequate oxygenation. Perianesthesia providers must consider anesthetic, ventilatory, and pharmacologic implications when proposing, providing, and recovering anesthesia for the patient with MG., (Copyright © 2018 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.)

Background: The cannabinoid system may be involved in the humoral mechanisms at the neuromuscular junction. Ultramicronized-palmitoylethanolamide (μm-PEA) has recently been shown to reduce the desensitization of Acetylcholine (ACh)-evoked currents in denervated patients modifying the stability of ACh receptor (AChR) function., Objective: To analyze the possible beneficial effects of μm-PEA in patients with myasthenia gravis (MG) on muscular fatigue and neurophysiological changes., Method: The duration of this open pilot study, which included an intra-individual control, was three weeks. Each patient was assigned to a 1-week treatment period with μm-PEA 600 mg twice a day. A neurophysiological examination based on repetitive nerve stimulation (RNS) of the masseteric and the axillary nerves was performed, and the quantitative MG (QMG) score was calculated in 22 MG patients every week in a three-week follow-up period. AChR antibody titer was investigated to analyze a possible immunomodulatory effect of PEA in MG patients., Results: PEA had a significant effect on the QMG score (p=0.03418) and on RNS of the masseteric nerve (p=0.01763), thus indicating that PEA reduces the level of disability and decremental muscle response. Antibody titers did not change significantly after treatment., Conclusion: According to our observations, μm-PEA as an add-on therapy could improve muscular response to fatigue in MG. The possible modulation of AChR currents as a means of eliciting a direct effect from PEA on the conformation of ACh receptors should be investigated. The co-role of cytokines also warrants an analysis. Given the rapidity and reversibility of the response, we suppose that PEA acts directly on AChR, though further studies are needed to confirm this hypothesis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Notwithstanding the amount of deliberate exercise, the daily patterns of active versus sedentary behavior have a major influence on health outcomes [1]. Patterns of habitual active and sedentary behavior in Myasthenia Gravis (MG) patients, as well as their possible relations to disease activity, are not known., Objective: To evaluate baseline patterns of physical and sedentary behavior in MG patients., Methods: Activity patterns of twenty-seven MG patients were assessed by a Dynaport MoveMonitor (McRoberts) accelerometer, worn for seven consecutive days. The amount of time spent in moderate and vigorous intensity activities, physical activity level (PAL), number of steps/day and sedentary time were assessed and correlations to disease severity were analyzed. The results were compared to general recommendations and published data of healthy individuals and to data of patients with the chronic disorders chronic obstructive pulmonary disease (COPD) and mitochondrial myopathy., Results: MG patients had sedentary behavior during 78±7% of the day. There was neither a correlation between disease severity and number of steps/day (R = -0.15; p = 0.56) nor between disease severity and PAL (R = 0.33; p = 0.26). Nevertheless, the MG patients met the recommendations of daily deliberate exercise (181±158 MET min/day). PAL was lower in MG patients (1.5±0.138) than in healthy individuals (1.67±0.145, p < 0.00001)., Conclusion: Although a majority of MG patients meet the recommendations of deliberate exercise, their baseline physical activity levels are dominated by sedentary behavior. In comparison with a healthy population, MG patients are less physically active, but the reason for this remains unclear with no correlations between disease severity and physical activity patterns.

Background and Purpose: Approximately, 50% of myasthenia gravis (MG) patients initially present with purely ocular symptoms. Of these, about 60% will develop secondary generalized MG, typically within 2 years. Risk factors for secondary generalization are still controversial. In this study, we reviewed clinical parameters, thymic pathologies and medical treatments of MG patients with purely ocular symptoms at onset to investigate risk factors for secondary generalization., Methods: In this monocentric retrospective study, we reviewed consecutive patients who underwent robotic thymectomy between January 2003 and October 2017 in Charite Universitaetsmedizin Berlin. We used univariate and multivariate Cox proportional hazards regression models to identify factors associated with secondary generalization. Survival curves were plotted using Kaplan-Meier method and log-rank tests were performed to analyze the association between corticosteroids use and secondary generalization in subgroups defined by anti-AChR antibody status and thymic pathology., Results: One hundred and eighty of 572 MG patients who underwent robotic thymectomy were eligible for inclusion, of whom 110 (61.1%) developed a secondary generalized MG over a mean follow-up time of 23.6 months. The presence of a thymoma (HR 1.659, 95% CI (1.52-2.617), P = 0.029) was the only risk factor for secondary generalization in our series. Treating with corticosteroids was associated with a lower conversion rate in ocular myasthenia patients with thymic hyperplasia (n = 55, P = 0.028), but not with other thymic pathologies including thymoma and normal or atrophic thymus., Conclusions: The conversion rate in ocular myasthenia was high in our series, predicted by the presence of a thymoma. Our findings suggest that corticosteroids can prevent secondary generalization in ocular myasthenia patients with thymic hyperplasia, which requires further research.

Objectives: To investigate if monopolar (MN) and concentric (CN) electrodes are equivalent for volitional contraction jitter estimation in orbicularis oculi (OO), and to study the effect of selecting a specific high-pass filter., Methods: We studied neuromuscular jitter in OO on both sides in 100 consecutive patients with a clinical diagnosis of ocular myasthenia gravis (MG). We used either MN (50 patients) or CN (50 patients) electrodes in individual patients, according to a randomised protocol, with a 1kH high pass filter on one side and a 3kH filter on the other. Ten or more potential pairs were studied on each side., Results: 48 patients had a definite clinical diagnosis of ocular MG, and 52 of mimicking-disorders, who were analysed as controls. In controls, jitter (MCD) showed a normal distribution independent of the electrode type or filter settings. The mean jitter value and the number of abnormal pairs (>10%) was similar in MN and CN recordings, with both 1 kHz and 3 kHz filters. Sensitivity was 73% for mean jitter and 94% for number of abnormal pairs. Specificity was 100%., Conclusions: The jitter in OO using MN or CN was similar in controls and the diagnostic sensitivity was similar using either electrode in patients with ocular MG. The use of high-pass filters of 1 or 3 kHz did not influence these results., Significance: MN and CN are both suitable for determining volitional jitter in OO., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Purpose: As most of patients with Myasthenia Gravis have limitations in their physical functioning, many experience changes in psychological states and often have depression. The objective of the current study was to examine the roles of communication with medical professionals, patients' loneliness, and patients' depression, in relation to their effects on the patients' quality of life., Methods: For 120 patients with MG of 18 years and older, demographic variables, along with communication with medical professionals, loneliness, depression, and quality of life were measured., Results: As a result, people suffering from MG experienced lower quality of life when their career has changed due to the illness. At the same time, depression was a significant predictor of their quality of life, both in physical and mental domains., Conclusions: The implications for clinical settings and the suggestions for future research are discussed., Competing Interests: The authors have declared that no competing interests exist.

Background: Dislocation following total hip arthroplasty is mainly caused by malposition. However, the coexistence of neuromuscular disorders is also considered a risk for dislocation due to excessive hip joint laxity. To minimize risk of dislocation, preoperative planning using combined anteversion has been widely used. The recommended combined anteversion angle (the total of cup and stem anteversion angles) is 50 ± 10°., Case Presentation: A 33-year-old Japanese woman underwent elective total hip arthroplasty due to osteonecrosis of the femoral head associated with corticosteroid pulse therapy for myasthenia gravis. Intraoperatively, no tendency of dislocation was found when simulating an evoking position under general anesthesia. In postoperative X-ray and computed tomography scans, cup inclination, cup anteversion, and stem anteversion angles were 37°, 13°, and 35° respectively. The resulting combined anteversion was 48°, which was set as the target along with accurate placement. Her postoperative course was normal and she was discharged without adverse events. Three months postoperatively, due to worsening of myasthenic weakness in her lower extremities while resting, she tended to raise her left limb up using both hands for sitting up. An anterior dislocation occurred when her legs were in a figure-of-four position. She was brought to an emergency department, and reduction of dislocation was performed. It was inferred that myasthenic crisis in the affected limb enabled excessive passive motion due to joint hyperlaxity. At the end of 2016, elective total hip arthroplasty on the contralateral side was performed. Cup anteversion, stem anteversion, and the combined anteversion angles were 27°, 24°, and 51° respectively. We instructed her to exercise care during passive leg movement, which may worsen her myasthenic condition. She returned to a normal life and was able to walk long distances without a cane. No recurrence of dislocation was seen at final follow-up., Conclusions: Even if accurate component orientation is attained in total hip arthroplasty, patients with neuromuscular disorders such as myasthenia gravis have a potential risk of muscle weakness in the affected limb. Therefore, physicians' instructions and patients' careful attention are required to prevent dislocation due to excessive hip joint laxity under conditions of motor weakness.

Introduction: Clinical and electrophysiological studies to measures disease activity in juvenile myasthenia gravis (JMG) are limited., Methods: Retrospective review of the clinical profile, Myasthenia Gravis Foundation of America (MGFA) scores, serial stimulated jitter analysis (Stim-JA) of the orbicularis oculi muscle, grip strength, and spirometry of patients with JMG who were followed in a multidisciplinary clinic was performed., Results: Thirteen patients with JMG (9 females) with mean age of 13.2 ± 4.8 years and follow-up duration of 25.3 ± 8.3 months (range, 6-39) with ≥ 2 Stim-JA recordings were included. The mean jitter, mean percentage of apparent single-fiber action potentials (%ASFAP) with increased jitter, and mean %ASFAP with blocking at baseline values (77.3 ± 54.7 µs, 64.3% ± 35.8%, 39% ± 38.6%, respectively) and at follow-up (53 ± 45.4 µs, 51.2% ± 34.5%, 17% ± 29.4%, respectively) were abnormal; however, no statistically significant interval difference was noted. The electrophysiological data correlated significantly with Myasthenia Gravis Foundation of America (MGFA) class. Grip strength and spirometry did not correlate with MGFA class., Discussion: Stimulated jitter values are sensitive biomarkers in JMG. Muscle Nerve 58: 729-732, 2018., (© 2018 Wiley Periodicals, Inc.)

Background: Myasthenia gravis (MG) is characterized by reduced muscle endurance and often leads to respiratory complications., Objective: A long-term respiratory muscle endurance training (RMET) based on normocapnic hyperpnea was introduced for the first time in MG patients. We investigated RMET effects on respiratory endurance (RE), MG symptoms, lung function and physical fitness and compared the results with a control group (CG)., Methods: The training period consisted of four weeks intensive training (IT; five 30-min training sessions per week) followed by twelve months maintenance training (MT; five 30-min training sessions over two weeks). Eighteen patients with mild to moderate MG participated as the training group (TG), six patients served as CG. RE, lung function, MG score and physical fitness were tested before and after IT and after three to twelve months of MT., Results: Only 12 TG patients completed the entire training period. Thirteen months of training significantly increased RE measured as time until exhaustion (T lim ) to 412% of baseline (P < 0.001). The MG score improved from 0.67±0.09 to 0.41 ± 0.1 (p = 0.004), and the number of squats per minute as a measure of physical fitness increased in the TG to 160% of baseline (p = 0.015). While lung function did not change during the training period, we observed a modulation in the breathing pattern at rest with prolonged expiration (122% of baseline, p = 0.028). In addition, TG reported subjective improvements in MG symptoms, respiratory symptoms and physical fitness by 49%, 58% and 64%, respectively (P < 0.001). No significant changes were observed in the CG., Conclusion and Significance: This is the first controlled long-term RMET study in MG patients. The results demonstrated that this normocapnic hyperpnea training is feasible and beneficial for patients with mild to moderate MG and is a valuable supplement to conventional drug treatment., (Copyright © 2018. Published by Elsevier Ltd.)

Introduction: Although immunotherapies such as prednisone are effective in treating myasthenic muscle weakness, their effect on resolution of myasthenic-induced persistent ophthalmoparesis is unknown., Methods: We observed patients with myasthenia gravis during their first year of immunotherapy, documenting ophthalmoplegia scores and drug doses., Results: Seventy-six of 87 cases had persistent ophthalmoparesis. With immunotherapy, the median time to resolution of ophthalmoparesis was 7 months, and 37% of cases resolved within 3 months. Patients starting therapy within 12 months of symptom onset were twice as likely to have resolution in the first year (P = 0.028). Resolution of ophthalmoparesis within 3 months, compared with later resolution, was associated with higher initial prednisone doses (mean 0.5 vs. 0.3 mg/kg/day; P = 0.014). However, 25% of the higher dose group also received intravenous immunoglobulin/plasma exchange; after their exclusion, the finding was not significant., Discussion: One-third of cases with myasthenic ophthalmoparesis resolved within 3 months of immunotherapy, particularly in response to more aggressive immunotherapy. Muscle Nerve 58: 542-549, 2018., (© 2018 Wiley Periodicals, Inc.)

Background and Purpose: Diagnosis of pharyngeal dysphagia caused by myasthenia gravis (MG) based on clinical examination alone is often challenging. Flexible endoscopic evaluation of swallowing (FEES) combined with Tensilon (edrophonium) application, referred to as the FEES-Tensilon test, was developed to improve diagnostic accuracy and to detect the main symptoms of pharyngeal dysphagia in MG. Here we investigated inter- and intra-rater reliability of the FEES-Tensilon test and analyzed the main endoscopic findings., Methods: Four experienced raters reviewed a total of 20 FEES-Tensilon test videos in randomized order. Residue severity was graded at four different pharyngeal spaces before and after Tensilon administration. All interpretations were performed twice per rater, 4 weeks apart (a total of 160 scorings). Intra-rater test-retest reliability and inter-rater reliability levels were calculated., Results: The most frequent FEES findings in patients with MG before Tensilon application were prominent residues of semi-solids spread all over the hypopharynx in varying locations. The reliability level of the interpretation of the FEES-Tensilon test was excellent regardless of the rater's profession or years of experience with FEES. All four raters showed high inter- and intra-reliability levels in interpreting the FEES-Tensilon test based on residue clearance (kappa = 0.922, 0.981). The degree of residue normalization in the vallecular space after Tensilon application showed the highest inter- and intra-rater reliability level (kappa = 0.863, 0.957) followed by the epiglottis (kappa = 0.813, 0.946) and pyriform sinuses (kappa = 0.836, 0.929)., Conclusion: Interpretation of the FEES-Tensilon test based on residue severity and degree of Tensilon clearance, especially in the vallecular space, is consistent and reliable., (© 2018 EAN.)

Background: Isolated ocular myasthenia gravis (MG) is sparingly common in children relative to adults, ranging from 71% to 93% of all children with MG., Purpose: We aimed to characterize the ocular manifestations and outcomes in children with isolated ocular MG., Methods: Medical records of consecutive 62 subjects less than 15 years of age with ocular MG, were retrospectively reviewed. Demographic data, presenting ocular features, types and variabilities of duction limitation, MG confirmatory tests, types of and responses to treatment, and generalized MG conversion were reviewed., Results: Mean age at onset and follow-up time were 49 months (range, one to 173 months) and 95 months (range, six to 226 months), respectively. Female-to-male ratio was 1.5:1. Initially, ptosis was found in 60 subjects (96.8%), while duction limitation was observed in 28 subjects (45.2%). Total ophthalmoparesis was the most common type of duction limitation. Variability of duction limitation was found in 68% of subjects during the follow-up. Pyridostigmine alone was the most common medication used (48.4%); ptosis was more responsive to therapy than duction limitation. Conversion to generalized MG occurred in 19.4% of subjects, with a mean interval to conversion of nine months after symptom onset. Most conversions (91.7%) occurred in the first two years., Conclusions: Ptosis was more responsive to treatment than duction limitation. Thus other treatment modalities, as well as strabismic amblyopia screening, should be considered in children with prolonged duction limitation that is refractory to medication. In contrast with adults, a much lower proportion of children converted to generalized MG. This may explain the higher prevalence of isolated ocular MG among the juvenile population., (Copyright © 2018. Published by Elsevier Inc.)

Introduction: The aim of this study was to define the diagnostic accuracy of concentric needle (CN)-jitter in newly diagnosed myasthenia gravis (MG) patients and to compare CN-jitter with repetitive nerve stimulation., Methods: In 30 MG patients, repetitive nerve stimulation in 4 muscles (orbicularis oculi, nasalis, trapezius and abductor digiti minimi) and CN-jitter of extensor digitorum (ED) and frontalis muscles were evaluated., Results: Twenty-eight of 30 patients (93%) had high jitter in at least one muscle. Repetitive nerve stimulation was abnormal in 23 of the patients (77%). Eighty-six percent of the patients in whom repetitive nerve stimulation test was negative could be diagnosed with CN-jitter. The most frequent muscle showing abnormal decrement was orbicularis oculi. The results of CN-jitter were similar between patients with different serological groups. Of 13 patients with generalized weakness, all had high jitter in both muscles studied whereas of 17 patients only with ocular weakness, 15 had high jitter in at least one muscle studied., Conclusion: Abnormal RNS was present in 77% of newly diagnosed MG patients, being less than CN-jitter (93%) but more than antibody positivity (73.3%)., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Competing Interests: Competing interests: None declared.

Purpose: To evaluate the response to corticosteroid therapy as a primary treatment for ocular myasthenia gravis., Methods: Patients diagnosed as having ocular myasthenia gravis by an acetylcholine receptor binding antibody test between January 2011 and September 2015 were included in the study and started receiving treatment with a corticosteroid. Patients with a blowout fracture, hyperthyroidism, diabetes mellitus, hypertension, cardiovascular disease, or history of strabismus surgery were excluded. Disappearance of diplopia and ptosis were considered a response to treatment., Results: Methylprednisolone therapy was administered to 29 patients (19 men and 10 women; average age: 49 ± 16.5 years) as an initial treatment. A total of 6 patients were lost to follow-up. Twenty-three of 29 patients (82.6%) were regarded as having presented a response to treatment. The average treatment duration was 3 weeks for patients responding to primary treatment. Eight patients complained of adverse effects from steroid therapy such as heartburn, insomnia, weight gain, and myalgia., Conclusions: A corticosteroid could be considered as an initial treatment for patients diagnosed as having ocular myasthenia gravis by an acetylcholine receptor binding antibody test. [J Pediatr Ophthalmol Strabismus. 2018;55(5):339-342.]., (Copyright 2018, SLACK Incorporated.)

Background: The cardinal symptoms of auto-immune myasthenia gravis are fatigue and weakness. Endurance events such as marathon running would seem incompatible with this chronic disease. Many patients stop sport altogether. There is limited literature of patients with auto-immune myasthenia gravis undergoing regular endurance exercise., Case Presentation: We report the case of a 36-year-old female who began long-distance running whilst experiencing initial symptoms of myasthenia gravis. She was diagnosed with auto-immune myasthenia gravis and whilst advised to stop all sport, her way of fighting and living with this chronic and unpredictable disease was to continue running to maintain a healthy body and mind. Despite suffering from ocular, bulbar and localized limb fatigability, she managed to complete multiple marathons and achieve disease stability with cholinesterase inhibitors., Conclusions: Marathon and half-marathon running lead to distinct changes in mediators of inflammation in an exercise-dose-dependent manner. Despite symptoms of weakness and fatigue in certain muscles in myasthenia gravis, physical exertion remains possible and may not worsen symptoms as demonstrated in this case and recent studies. The immunomodulatory role of exercise could be considered in this case however this hypothesis remains to be confirmed in future studies with quantitative data.

Background: We present a patient fulfilling the electrophysiological criteria for definite chronic inflammatory demyelinating polyneuropathy (CIDP), antibody-positive myasthenia gravis (MG), and membranous glomerulonephritis (MGN) confirmed by biopsy. To our knowledge, this is the first case of the concomitant appearance of these three autoimmune diseases in a single patient., Case Representation: A 42-year-old Caucasian male presented with rapidly progressive gait disturbance, distal weakness of the lower extremities, ascending hypoesthesia, impaired fine motor skills, and beginning cranial nerve palsy showing dysarthrophonia, facial paralysis, and eye movement abnormalities and was diagnosed as rapid onset (atypical) CIDP. After 3 months, the patient complained of increasing physical exhaustion, reduction of his walking distance, worsening of the residual dysphagia, and dysarthria with an inability to swallow. AChR antibodies (17.0 nmol/L, RF < 0.4) and titin antibodies were positive and repetitive nerve stimulation showed an abnormal decrement matching the criteria of myasthenia gravis. Over time the patient developed severe acute-on-chronic renal failure with high-grade proteinuria resulting in generalized edema followed by secondary hyperparathyroidism and dialysis-dependent renal failure. Renal biopsy confirmed beginning anti-phospholipase A2 receptor antibody membranous nephropathy., Conclusion: All three diseases are of autoimmune origin with distinctive immunopathogenetic mechanisms. The present case of CIDP, MG, and MGN occurring in one patient indicates a common underlying immune mechanism in these distinct conditions, including the involvement of autoantibodies and T cells.

Myasthenia gravis is one of the most common disorders that affect neuromuscular transmission. It is currently one of the most understood and characterised autoimmune disorders Its typical symptoms are fluctuating weakness and fatigue that affects a combination of ocular muscles, bulbar functions, as well as limb and respiratory muscles, which are due to an immune attack against the postsynaptic membrane of the neuromuscular junction. The diagnosis of myasthenia gravis is based on clinical and serological test. It is a disease that can be effectively controlled with the current therapeutic lines, even achieving a complete remission. An update of this interesting disorder is now presented., (Copyright © 2018 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.)

Myasthenia gravis is a relatively common neuromuscular disorder, with ocular myasthenia gravis being a subset defined as myasthenia gravis limited to the orbicularis, levator, and extraocular muscles. Patients with ocular myasthenia gravis can have disabling diplopia or functional blindness from ptosis and in most cases treatment is required. Like generalized myasthenia gravis, there are a variety of treatments available that include pyridostigmine, immunosuppression, intravenous immunoglobulin, plasmapheresis, thymectomy, lid crutches, ptosis surgery, and extraocular muscle surgery. Unfortunately, there is limited data on the use of individual treatments in ocular myasthenia gravis and no data comparing treatments. Using a combination of available data on treatment of generalized myasthenia gravis, data on treatment of ocular myasthenia gravis, best practices, and clinical experience we will provide a rational framework for treatment of ocular myasthenia gravis., (Copyright 2018 Asia-Pacific Academy of Ophthalmology.)

Introduction: Myasthenia gravis (MG) is an autoimmune neuromuscular disorder with no cure and conventional treatments limited by significant adverse effects and variable benefit. In the last decade, therapeutic development has expanded based on improved understanding of autoimmunity and financial incentives for drug development in rare disease. Clinical subtypes exist based on age, gender, thymic pathology, autoantibody profile, and other poorly defined factors, such as genetics, complicate development of specific therapies. Areas covered: Clinical presentation and pathology vary considerably among patients with some having weakness limited to the ocular muscles and others having profound generalized weakness leading to respiratory insufficiency. MG is an antibody-mediated disorder dependent on autoreactive B cells which require T-cell support. Treatments focus on elimination of circulating autoantibodies or inhibition of effector mechanisms by a broad spectrum of approaches from plasmapheresis to B-cell elimination to complement inhibition. Expert commentary: Standard therapies and those under development are disease modifying and not curative. As a rare disease, clinical trials are challenged in patient recruitment. The great interest in development of treatments specific for MG is welcome, but decisions will need to be made to focus on those that offer significant benefits to patients.

Background: There are limited data on the characteristics, incidence, and mortality of patients with myasthenia gravis (MG) admitted to the ICU., Aims: To study the epidemiology, characteristics and outcome of patients with MG in Australian and New Zealand (ANZ) ICUs over a decade., Methods: We performed a retrospective observational, cross sectional study of data from the Australian and New Zealand Intensive Care Society (ANZICS) Adult Patient Database (APD). We collected data on all adult patients admitted with a primary diagnosis of MG to 159 Australian and 19 New Zealand ICUs between January 1, 2005 and December 31, 2015.We extracted detailed relevant data and performed statistical assessment., Results: We identified 245 patients admitted to ICU with the primary diagnosis of MG, with an incidence increasing from 1 to 2.5 per thousand ICU admissions (P<0.0001) and from 1 to 2.2 per million people (P=0.02). Mean age was 60years with more patients being female (53.7% vs 47.3%) and 91 (37.1%) patients received mechanical ventilation. Hospital mortality occurred in 13 (5.3%) patients with a mortality rate lower than in other ICU patients., Conclusions: In ANZ, the ICU and population incidence of MG has increased over the last decade. However, its mortality rate was low., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To investigate the clinical character, diagnosis and treatment of chronic inflammatory demyelinating polyneuropathy accompanying myasthenia gravis so as to improve the understanding of such diseases., Materials and Methods: A case of chronic inflammatory demyelinating polyneuropathy combined with myasthenia gravis were analyzed retrospectively with review of the literature., Results: This man was presented with chronic progressive sensory symptoms, flaccid tetraparesis, areflexia and protein-cell dissociation of cerebrospinal fluid. Nerve conduction study was indicative of demyelinating neuropathy. He was suspected as chronic inflammatory demyelinating polyneuropathy and treated with high-dose glucocorticoids. However, his condition worsened. Four months later, he was admitted and was diagnosed as combination of chronic inflammatory demyelinating polyneuropathy and myasthenia gravis. Good clinical results were observed after he was treated with pyridostigmine bromide, prednisone and mycophenolate mofetil., Conclusions: This case warns clinicians to be aware of these two diseases presenting in the same patient, and the possible implications on treatment choices. A common immunological abnormality might exist in this rare association, but it still remains unknown.

Objective: Myasthenia gravis (MG) is an archetypic disorder of neuromuscular junctions (NMJs) and autoantibody-mediated disease causing fatigable weakness of skeletal muscles with an ocular onset in up to 85%. The aim of this study was to detect extra ocular muscles (EOMs) abnormalities in MG patients using ocular vestibular evoked myogenic potential (oVEMP) n10 response., Methods: The oVEMP was performed on 40 myasthenia gravis patients that were divided into three groups: newly diagnosed (10 patients), uncontrolled on treatment (15 patients) and controlled on treatment (15 patients) groups in addition to a control group of 10 subjects. Also a comparison of oVEMP response was held between patients with generalized and ocular MG., Results: The oVEMP n10 showed significant difference between the 3 study groups and the control. The n10 showed no significant difference between the newly diagnosed group and the other 2 groups. There was also significant difference between uncontrolled and controlled on treatment group and between generalized and ocular types of myasthenic patients., Conclusion: The oVEMP can be usefully used in diagnosis of new MG patients as regard n10 amplitude, threshold and AR except n10 latency with no therapeutic or monitoring value of oVEMP in MG., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objectives: Extended thymectomy is a treatment option for myasthenia gravis (MG), but the surgical indications are controversial. Pathologic features of the thymus can be used to predict surgical outcomes, but there is no reliable method for evaluating these characteristics preoperatively. The purpose of this study was to determine whether anterior mediastinal tissue volume, as measured via 3-dimensional computed tomography (3DCT) volumetry, correlates with serum anti-acetylcholine receptor antibody (AChRAb) levels in patients undergoing thymectomy for myasthenia gravis. Therefore, we investigated the relationships among anterior mediastinal tissue volume determined by 3DCT volumetry and AChRAb levels., Methods: The subjects were 28 patients who underwent extended thymectomy and were enrolled retrospectively. We measured volume of the anterior mediastinum and calculated the volumes of more than -30 Hounsfield units (V -30 ) by using 3DCT volumetry and compared them with perioperative AChRAb levels. The significance of their volumes in MG was examined by comparison with 53 patients without MG., Results: V -30 values were related to age and were significantly greater in patients with MG than in patients without MG (P < .001). V -30 values were correlated positively with preoperative AChRAb levels (ρ = 0.505, P = .006) and inversely with the post/preoperative AChRAb ratio (ρ = -0.453, P = .018). The histologic nonadipose tissue ratio was correlated with the V -30 /volume of the anterior mediastinum (ρ = 0.700, P < .001)., Conclusions: This method for evaluation of the anterior mediastinal tissue volume and AChRAb production may be helpful in establishing a treatment plan for MG., (Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Seronegative myasthenia gravis (MG) is a generalized form of MG that is diagnosed on the basis of clinical symptoms, electrophysiological testing, and pharmacological responses, in the absence of a seropositive status for anti-acetylcholine receptor (AChR) antibodies. Generalized MG that is seronegative for anti-AChR, anti-muscle-specific kinase (MuSK), and anti-low density lipoprotein receptor related protein 4 (Lrp4) antibodies is known as triple-seronegative MG. We here describe a case of triple-seronegative MG in an 8-year-old boy. His first symptom was dysphagia, at 3 years of age, and he subsequently developed ptosis, rhinolalia, and a waddling gait. A genetic analysis was conducted to exclude the possibility of congenital myasthenia syndrome due to the patient's resistance to steroid therapy. His condition was successfully managed with tacrolimus therapy over a 5-year follow-up period. Recently, several studies have reported the therapeutic utility of tacrolimus in juvenile seropositive MG; in contrast, a few reports have described tacrolimus treatment in cases of seronegative MG. Our findings suggest that tacrolimus therapy is a safe and effective option for the treatment of juvenile seronegative MG., Competing Interests: The authors indicated no potential conflict of interest., (Georg Thieme Verlag KG Stuttgart · New York.)

This article discusses antibodies associated with immune-mediated myasthenia gravis and the pathologic action of these antibodies at the neuromuscular junctions of skeletal muscle. To explain how these antibodies act, we consider the physiology of neuromuscular transmission with emphasis on 4 features: the structure of the neuromuscular junction; the roles of postsynaptic acetylcholine receptors and voltage-gated Na + channels and in converting the chemical signal from the nerve terminal into a propagated action potential on the muscle fiber that triggers muscle contraction; the safety factor for neuromuscular transmission; and how the safety factor is reduced in different forms of autoimmune myasthenia gravis., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Myasthenic crisis is the life threatening maximal manifestation of myasthenia gravis. Severe dysphagia and respiratory insufficiency demand admission to an intensive care unit (ICU). At variance, the timely recognition and treatment of myasthenic exacerbation may prevent a manifesting crisis. This reviews deals with red flags that pronounce exacerbation and crisis. Myasthenic crisis is an important differential diagnosis of bulbar symptoms and dysphagia. We elaborate on a structured and comprehensive approach to myasthenic crisis on the ICU. Hallmarks of therapy are symptomatic treatment with acetylcholine esterase inhibitors, plasmapheresis or immunoadsorption, polyvalent immunoglobulins, an early start of steroids and immunosuppressants, namely azathioprine, and a consequent escalation to monoclonal antibody therapy, with rituximab being the first choice. Special demands in ICU treatments are a structured weaning concept, consequent treatment of comorbidities and complications, first and foremost infections, dysphagia management, and comprehensive prevention and treatments of delirium., Competing Interests: HS gibt keine Interessenskonflikte an. MS erhielt persönliche Referentenhonorare von Alexion, Bayer, Biogen, CSL Behring, Grifols, Merck, Miltenyi Biotec, Novartis, Roche, Teva., (© Georg Thieme Verlag KG Stuttgart · New York.)

Objective: We aimed to comprehensively evaluate cardiac autonomic function in patients with MG and to investigate the relationship between this disorder and disease duration, thymoma and acetylcholine receptor antibody positivity in cases of cardiac autonomic disorder., Methods: The study included 30 patients with MG and 30 age-matched healthy control subjects. Haemodynamic parameters (heart rate, systolic and diastolic blood pressure) and autonomic parameters (low frequency [LF], high-frequency [HF], sympathovagal balance [LF/HF], baroreceptor reflex sensitivity [BRS]) of the patients were automatically measured at rest and in a tilted position with the Task Force Monitor., Results: The mean systolic and diastolic blood pressure measurements obtained at rest and during the tilt test were higher in patients with MG. Sympathovagal balance has been disturbed in favour of sympathetic tone, and parasympathetic insufficiency has become more prominent. When baroreceptor sensitivity was used as the second parameter to evaluate autonomic heart functions, BRS at rest and during the tilt test was lower in the MG group compared with the control group., Discussion: These results suggest that sympathovagal balance has been disturbed in favour of sympathetic tone and that parasympathetic insufficiency has become more prominent. The current findings support the presence of cardiac autonomic involvement in patients with MG. The determination of cardiac autonomic function via noninvasive methods among patients with MG has high predictive value. The identification of autonomic dysfunction at an early stage and the early treatment of cardiovascular diseases can reduce morbidity and mortality.

Introduction: Ocular myasthenia gravis (OMG) is a common condition of the neuromuscular junction that may convert to generalized myasthenia gravis (GMG). Our aim in this study was to determine the conversion rate and predictive factors for generalization in OMG, in an Asian population., Methods: The investigation consisted of a retrospective study of OMG patients with a minimum 2 years of follow-up., Results: Among 191 patients with OMG, 155 had the minimum 2-year follow-up. The conversion rate at median follow-up (40.8 months) was 10.6% (95% confidence interval 7.9%-13.3%), and at the 2-year follow-up it was 7.7% (95% confidence interval 5.6%-9.8%). At baseline, the predictive factors for generalization were positive acetylcholine receptor antibodies (hazard ratio 3.71, P = 0.024), positive repetitive nerve stimulation (RNS) studies (hazard ratio 4.42, P = 0.003), and presence of radiologically presumed or pathologically confirmed thymoma (hazard ratio 3.10, P = 0.013)., Discussion: The conversion rate of OMG to GMG in Asian patients is low, as predicted by presence of acetylcholine receptor antibodies, presence of thymoma, and positive RNS studies. Muscle Nerve 57: 756-760, 2018., (© 2017 Wiley Periodicals, Inc.)

The non-vitamin K antagonist oral anticoagulant rivaroxaban is indicated in prevention and treatment of venous thromboembolism (VTE). A 60-year-old male patient complained of bilateral ptosis after administration of rivaroxaban for deep vein thrombosis (DVT). Myasthenia gravis (MG) was confirmed by positive serum antiacetylcholine receptor antibody test. No mediastinal thymoma was found. The ocular myasthenia reversed after discontinuing rivaroxaban treatment. Nevertheless, ptosis recurred and chronic oral pyridostigmine bromide treatment was necessary. The mechanism of MG development by rivaroxaban therapy is not completely understood. The development of rivaroxaban-induced autoimmune disease could be based on cross-reactivity between antibodies against rivaroxaban-derived antigens or by T-cell activation. To our knowledge, this report of ocular myasthenia by rivaroxaban administration is the first in the literature. Despite the benefits of rivaroxaban, it is important to recognize unexpected immune-related adverse events., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The neuromuscular junction is the point of contact between motor nerve and skeletal muscle, its vital role in muscle function is reliant on the precise location and function of many proteins. Congenital myasthenic syndromes (CMS) are a heterogeneous group of disorders of neuromuscular transmission with 30 or more implicated proteins. The use of animal models has been instrumental in determining the specific role of many CMS-related proteins. The mouse neuromuscular junction (NMJ) has been extensively studied in animal models of CMS due to its amenability for detailed electrophysiological and histological investigations and relative similarity to human NMJ. As well as their use to determine the precise molecular mechanisms of CMS variants, where an animal model accurately reflects the human phenotype they become useful tools for study of therapeutic interventions. Many of the animal models that have been important in deconvolving the complexities of neuromuscular transmission and revealing the molecular mechanisms of disease are highlighted.