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Introduction: The course of double-seronegative myasthenia gravis (DSNMG) during and after pregnancy has not been well described., Objective: To assess the course of DSNMG during pregnancy and within 6 months postpartum., Methods: A retrospective cohort study of women with DSNMG seen in the Duke Myasthenia gravis (MG) Clinic after 2003., Results: Review of the Duke MG Clinic Registry and electronic medical record identified 8 patients who became pregnant after MG onset; the mean age at disease onset was 17.6 (SD = 10.0) years. Increased MG symptoms were observed in the first and third trimester and, most commonly, postpartum in 6 of 18 pregnancies. Except for 1 infant who developed respiratory distress that required neonatal intensive care admission, all the newborns were healthy at birth., Conclusions: As in seropositive MG, increased MG symptoms during pregnancy and within 6 months postpartum is also seen in women with DSNMG., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction/aims: Myasthenia gravis (MG) with muscle-specific tyrosine kinase (MuSK) antibodies (MMG) is predominantly seen in women of childbearing age. Our objective in this study was to describe the course of MMG during pregnancy and within 6 months postpartum, and to document any effect on fetal health., Methods: A retrospective review was performed of medical records of patients with MMG seen in the Duke Myasthenia Gravis Clinic from 2003 to 2022. MMG patients with onset of MMG symptoms before or during pregnancy as well as within 6 months postpartum were reviewed., Results: A total of 14 pregnancies in 10 patients were included in our study cohort. Initial MG symptoms developed during pregnancy or within 6 months postpartum in six patients. Four patients had two pregnancies, three of whom developed MG during their first pregnancy. In the patients diagnosed before pregnancy, MG symptoms increased in five of eight patients during pregnancy or postpartum. Four patients required rescue therapy with plasma exchange or intravenous immunoglobulin during pregnancy or postpartum. One patient had a cesarean section after prolonged labor due to failure of progression. There were no other complications of pregnancy or delivery, and all infants were healthy at delivery., Discussion: As in non-MuSK MG, women with MMG may also have worsening or may develop initial MG symptoms during pregnancy or within 6 months postpartum. More aggressive medical therapy may be required for pregnant patients with MMG. Further study is needed to identify the mechanism and risk of worsening of MMG during pregnancy or postpartum., (© 2023 Wiley Periodicals LLC.)

Introduction/aims: The Duke Myasthenia Gravis (MG) Clinic Registry contains comprehensive physician-derived data on patients with MG seen in the Duke MG Clinic since 1980. The aim of this study was to report outcomes in patients seen in the clinic and treated according to the International Consensus Guidance statements., Methods: This is a retrospective cohort study of patients initially seen after 2000 and followed for at least 2 years in the clinic. Treatment goal (TG) was defined as achieving MGFA post-intervention status of "minimal manifestations" or better; PIS was determined by the treating neurologist. Time-to-event analysis, including Cox proportional hazards modeling, was performed to assess the effect of sex, acetylcholine receptor antibody (AChR-Ab) status, age at disease onset, distribution (ocular vs generalized), thymectomy, and thymoma on the time to achieve TG., Results: Among the 367 cohort patients, 72% achieved TG (median time less than 2 years). A greater proportion of patients with AChR-Abs and thymectomy achieved TG and they did so sooner than patients without these antibodies or thymectomy. Otherwise, there were no significant differences in these findings within the tested subgroups. The disease duration at the first Duke Clinic visit was shorter in patients who achieved TG than in those who did not., Discussion: These results demonstrate outcomes that can be achieved in patients with MG treated according to the current Consensus Guidance statements. Among other things, they can be used to determine the added value and potential role of new treatment modalities developed since 2018., (© 2023 Wiley Periodicals LLC.)

Purpose of Review: This article provides an overview of neuromuscular disorders in pregnancy, with a focus on diagnosis and management., Recent Findings: Neuromuscular disorders with issues that occur in pregnancy include conditions that are acquired (including autoimmune) or genetic; each requires a unique approach to management and treatment prepartum, peripartum, and postpartum. Guidance in the literature regarding management and treatment options is predominantly from case series and retrospective reviews. Treatment can be complex, particularly in autoimmune neuromuscular diseases, because of the risks of side effects of the treatments that may affect the patient and fetus., Summary: This article summarizes expectations, diagnosis, and management for a wide range of neuromuscular disorders in pregnancy., (Copyright © 2022 American Academy of Neurology.)

We consider epidemiological modeling for the design of COVID-19 interventions in university populations, which have seen significant outbreaks during the pandemic. A central challenge is sensitivity of predictions to input parameters coupled with uncertainty about these parameters. Nearly 2 y into the pandemic, parameter uncertainty remains because of changes in vaccination efficacy, viral variants, and mask mandates, and because universities' unique characteristics hinder translation from the general population: a high fraction of young people, who have higher rates of asymptomatic infection and social contact, as well as an enhanced ability to implement behavioral and testing interventions. We describe an epidemiological model that formed the basis for Cornell University's decision to reopen for in-person instruction in fall 2020 and supported the design of an asymptomatic screening program instituted concurrently to prevent viral spread. We demonstrate how the structure of these decisions allowed risk to be minimized despite parameter uncertainty leading to an inability to make accurate point estimates and how this generalizes to other university settings. We find that once-per-week asymptomatic screening of vaccinated undergraduate students provides substantial value against the Delta variant, even if all students are vaccinated, and that more targeted testing of the most social vaccinated students provides further value., Competing Interests: The authors declare no competing interest., (Copyright © 2021 the Author(s). Published by PNAS.)

Lymphatic dysfunction is associated with the progression of several vascular disorders, though currently, there are limited strategies to promote new lymphatic vasculature (i.e., lymphangiogenesis) to restore lost lymphatic function. One promising approach to stimulate lymphangiogenesis involves delivering endothelial progenitor cells (EPCs), which are naturally involved in de novo blood vessel formation and have recently been identified to include a lymphatic subpopulation. However, the contribution of lymphatic EPCs in lymphangiogenesis is not clear and challenges with maintaining the activity of transplanted EPCs remain. Thus, the objective of this study was to isolate lymphatic EPCs from human umbilical cord blood and characterize their role in the initial stages of blood or lymphatic vasculature formation. Furthermore, this study also tested the applicability of alginate hydrogels to deliver lymphatic EPCs for a possible therapeutic application. We postulated and confirmed that blood and lymphatic EPC colonies could be isolated from human umbilical cord blood. Additionally, EPC populations responded to either angiogenic or lymphangiogenic growth factors and could stimulate their respective mature endothelial cells in vasculature models in vitro. Finally, lymphatic EPCs maintained their ability to promote lymphatic sprouts after prolonged interactions with the alginate hydrogel microenvironment. These results suggest EPCs have both a blood and a lymphatic population that have specific roles in promoting revascularization and highlight the potential of alginate hydrogels for the delivery of lymphatic EPCs. STATEMENT OF SIGNIFICANCE: Despite the potential therapeutic benefit of promoting lymphatic vasculature, lymphangiogenesis remains understudied. One appealing strategy for promoting lymphangiogenesis involves delivering lymphatic endothelial progenitor cells (EPCs), which are a subpopulation of EPCs involved in de novo vessel formation. Here, we investigate the role of isolated blood and lymphatic EPC subpopulations in promoting the early stages of vascularization and the utility of alginate hydrogels to deliver lymphatic EPCs. We determined that EPCs had two populations that expressed either blood or lymphatic markers, could stimulate their respective mature vasculature in tissue constructs and that alginate hydrogels maintained the therapeutic potential of lymphatic EPCs. We anticipate this work could support promising biomaterial applications of EPCs to promote revascularization, which could have many therapeutic applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: The immunopathology of autoimmune seronegative myasthenia gravis (SN MG) is poorly understood. Our objective was to determine immune profiles associated with a diagnosis of SN MG., Methods: We performed high-dimensional flow cytometry on blood samples from SN MG patients (N = 68), healthy controls (N = 46), and acetylcholine receptor antibody (AChR+) MG patients (N = 27). We compared 12 immune cell subsets in SN MG to controls using logistic modeling via a discovery-replication design. An exploratory analysis fit a multinomial model comparing AChR+ MG and controls to SN MG., Results: An increase in CD19 + CD20 - CD38 hi plasmablast frequencies was associated with lower odds of being a SN MG case in both the discovery and replication analyses (discovery P-value = .0003, replication P-value = .0021). Interleukin (IL) -21 producing helper T cell frequencies were associated with a diagnosis of AChR+ MG (P = .004)., Conclusions: Reduced plasmablast frequencies are strongly associated with a SN MG diagnosis and may be a useful diagnostic biomarker in the future., (© 2020 Wiley Periodicals LLC.)

Background: Patients with myasthenia gravis (MG) may be particularly vulnerable during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic due to risk of worsening disease during infection, potential adverse impacts of coronavirus disease 2019 (COVID-19) treatments on neuromuscular transmission, and a limited ability to fight off infection related to immunosuppressive treatments. Our goal is to understand how patients are experiencing the COVID-19 pandemic, including where they receive relevant information, how it has affected medical care, and what measures they use to protect themselves., Methods: This is a prospective online survey study at large academic practice. All patients with a neuromuscular junction disorder diagnosis code in the Duke Health System were invited to participate., Results: One thousand eight hundred and forty eight patients were approached to participate and 75 completed the survey between 16 April 2020 and 28 May 2020. The most frequently used information sources were non-presidential federal government (75%), state government (57%), local healthcare provider (37%), and television news (36%). Non-presidential federal government (80%), local healthcare providers (55%), state government (33%), and patient support organizations (29%) were considered the most trusted information sources. Thirty-three (44%) of survey responders had attended a telemedicine visit. Patients were taking recommended precautions during the pandemic and remained very concerned (69%) about COVID-19. Generalized Anxiety Disorder-7 scores were moderate-severe in 20% of responders., Conclusions: Healthcare providers, the government, and patient organizations play a critical role in communicating with the MG patient community. Use of targeted messaging strategies by these groups to convey accurate information may increase effectiveness and lead to more informed patients with reduced anxiety., (© 2020 Wiley Periodicals LLC.)

Introduction: The Duke Myasthenia Gravis (MG) Clinic Registry is a disease-specific database containing physician-derived data from patients seen in the Duke MG Clinic since 1980., Methods: Data from 1060 MG patients initially seen between 1980 and 2008 were reviewed., Results: Fifty-four percent were male. Symptoms began after age 50 in 66% of males and 42% of females. Peak onset age in males was in their 60's; females had no predominant onset age. Onset age for both sexes increased from 1980 to 2008. Thymoma was present in 8.5%. Weakness was limited to ocular muscles for at least 2 y in 22% and became generalized later in 8.3% of these. Acetylcholine receptor antibodies were present in 78% overall, 82% with generalized MG and 52% with ocular MG (OMG). The distribution of MG disease class was similar in males and females, except that a greater proportion of women experienced myasthenic crisis and men were more likely to have OMG., Discussion: Data in the Registry permit comprehensive and longitudinal analysis of a validated MG population. Analysis of Registry data shows that the frequency of AChR antibody negative MG, ocular MG, and thymoma are similar to other reports, but the onset age and proportion of males have progressively increased compared to studies published more than 20 y ago. These observations demonstrate the value of collecting comprehensive clinical information and comparing historic and contemporary populations. Other potential uses of Registry data include comparison of outcome measures in different disease subgroups and the response to specific treatments., (© 2020 Wiley Periodicals LLC.)

Objectives: To approximate the rate of familial myasthenia gravis and the coexistence of other autoimmune disorders in the patients and their families., Design: Retrospective cohort study., Setting: Clinics across North America., Participants: The study included 1032 patients diagnosed with acetylcholine receptor antibody (AChR)-positive myasthenia gravis., Methods: Phenotype information of 1032 patients diagnosed with AChR-positive myasthenia gravis was obtained from clinics at 14 centres across North America between January 2010 and January 2011. A critical review of the epidemiological literature on the familial rate of myasthenia gravis was also performed., Results: Among 1032 patients, 58 (5.6%) reported a family history of myasthenia gravis. A history of autoimmune diseases was present in 26.6% of patients and in 28.4% of their family members., Discussion: The familial rate of myasthenia gravis was higher than would be expected for a sporadic disease. Furthermore, a high proportion of patients had a personal or family history of autoimmune disease. Taken together, these findings suggest a genetic contribution to the pathogenesis of myasthenia gravis., Competing Interests: Competing interests: RJB served as a consultant for NuFactor and Momenta Pharmaceutical and receives research support from PTC Therapeutics, Ra Pharma, Orphazyme, Sanofi Genzyme, FDA OOPD, NIH and PCORI. MB reports grant support from Muscular Dystrophy Association, ALS Association, ALS Recovery Fund, Kimmelman Estate, Target ALS, Eli Lilly & Company and the National Institutes of Health (NIH) during the conduct of the study. He also reports grant support from FDA, CDC and DOD; research support from Alexion Pharmaceuticals, UCB, Cytokinetics, Neuraltus, Biogen and Orphazyme A/S; and personal fees from NMD Pharma, Ra Pharmaceuticals, Mitsubishi-Tanabe, Avexis, UCB and Denali outside the submitted work. VC served as a consultant for review and expert testimony for the Department of Health and Human Services and the Department of Justice under the Vaccine Injury and Compensation Program. Dr Chaudhry has received royalty for total neuropathy score (TNS) patented (through Johns Hopkins University) for license of TNS use from AstraZeneca, Genentech, Seattle Genetics, Calithera Biosciences, Merrimack Pharmaceuticals, Levicept, and Acetylon Pharmaceuticals. MMD serves or recently served as a consultant for ArgenX, Catalyst, CSL-Behring, Kezar, Momenta, NuFactor, RMS Medical, Sanofi Genzyme, Shire Takeda, and Spark Therapeutics. Dr Dimachkie received grants from Alexion, Alnylam Pharmaceuticals, Amicus, Biomarin, Bristol-Myers Squibb, Catalyst, CSL-Behring, FDA/OOPD, GlaxoSmithKline, Genentech, Grifols, Mitsubishi Tanabe Pharma, MDA, NIH, Novartis, Sanofi Genzyme, Octapharma, Orphazyme, Sarepta Therapeutics, Shire Takeda, Spark, UCB Biopharma, Viromed & TMA. AE was a member of the advisory board for Alexion, a scientific award jury member for Grifols and safety data monitor for UCB. MF has received honoraria for serving on advisory boards for ARGNX pharma, Alexion. MF also has research support from Catalyst, Ra pharma, Amicus, Orphazyme, Alexion, Momenta and Alnylam. JFH reports research support and grants from Alexion Pharmaceuticals, argenx BVBA, Centers for Disease Control and Prevention, Muscular Dystrophy Association, NIH (including the National Institute of Neurologic Disorders and Stroke and the National Institute of Arthritis and Musculoskeletal and Skin Disease), PCORI (Patient-Centered Outcomes Research Institute) and Ra Pharmaceuticals; and nonfinancial support from Alexion Pharmaceuticals, argenx BVBA, Ra Pharmaceuticals and Toleranzia. HJK is funded by the Muscular Dystrophy Association (508240) and by NIH grant U54NS115054; is a consultant for Alnylam Pharmaceuticals, Ra Pharmaceuticals, and UCB Pharmaceuticals; and is CEO of ARC Biotechnology, LLC, which receives support from the NIH (R41NS110331). He serves on the Editorial Board of Experimental Neurology. MMe has received honoraria as a speaker and/or moderator from Alnylam, Akcea, Pfizer and CSL Behring. She has served on Advisory Boards for Pfizer, Alnylam and Akcea. She serves as an investigator for clinical trials with Alnylam and Biogen. SM has served on advisory board meetings for Alexion and argenx. MP served on advisory board for CSL Behring, Alexion pharmaceuticals, Argenx Pharmaceuticals and has been consultant for Momenta Pharmaceuticals. DPR receives research funding from a Sponsored Research Agreement from Cabaletta Bioscience. BJT holds an American and European Union patent on the clinical testing and therapeutic intervention for the hexanucleotide repeat expansion of C9orf72, and has received research grants from The Myasthenia Gravis Foundation, the Robert Packard Center for ALS Research, the ALS Association (ALSA), the Italian Football Federation (FIGC), the Center for Disease Control and Prevention (CDC), the Muscular Dystrophy Association (MDA), Merck and Microsoft Research. BJT receives funding through the Intramural Research Program at the National Institutes of Health., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

A detailed understanding of the role of Tfh cells in MuSK-antibody positive myasthenia gravis (MuSK-MG) is lacking. We characterized phenotype and function of Tfh cells in MuSK-MG patients and controls. We found similar overall Tfh and follicular regulatory (Tfr) T cell frequencies in MuSK-MG and healthy controls, but MuSK-MG patients exhibited higher frequencies of Tfh17 cells and a higher ratio of Tfh:Tfr cells. These results suggest imbalanced Tfh cell regulation, further supported by increased frequencies of CD4 T cells co-producing IL-21/IL-17 and IL-17/IFN-γ, and increased Tfh-supported IgG production. These results support a role for Tfh cell dysregulation in MuSK-MG immunopathology., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: To examine whether sustained minimal manifestation status (MMS) with complete withdrawal of prednisone is better achieved in thymectomized patients with myasthenia gravis (MG)., Methods: This study is a post hoc analysis of data from a randomized trial of thymectomy in MG (Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone Therapy [MGTX]). MGTX was a multicenter, randomized, rater-blinded 3-year trial that was followed by a voluntary 2-year extension for patients with acetylcholine receptor (AChR) antibody-positive MG without thymoma. Patients were randomized 1:1 to thymectomy plus prednisone vs prednisone alone. Participants were age 18-65 years at enrollment with disease duration less than 5 years. All patients received oral prednisone titrated up to 100 mg on alternate days until they achieved MMS, which prompted a standardized prednisone taper as long as MMS was maintained. The achievement rate of sustained MMS (no symptoms of MG for 6 months) with complete withdrawal of prednisone was compared between the thymectomy plus prednisone and prednisone alone groups., Results: Patients with MG in the thymectomy plus prednisone group achieved sustained MMS with complete withdrawal of prednisone more frequently (64% vs 38%) and quickly compared to the prednisone alone group (median time 30 months vs no median time achieved, p < 0.001) over the 5-year study period. Prednisone-associated adverse symptoms were more frequent in the prednisone alone group and distress level increased with higher doses of prednisone., Conclusions: Thymectomy benefits patients with MG by increasing the likelihood of achieving sustained MMS with complete withdrawal of prednisone., Clinicaltrialsgov Identifier: NCT00294658., Classification of Evidence: This study provides Class II evidence that for patients with generalized MG with AChR antibody, those receiving thymectomy plus prednisone are more likely to attain sustained MMS and complete prednisone withdrawal than those on prednisone alone., (© 2020 American Academy of Neurology.)

We describe a neonate with an unusual vascular ring formed by a right-sided aortic arch with associated coarctation and distal hypoplasia in the presence of an aberrant left subclavian artery. The descending aorta traveled behind the esophagus to descend on the left side of the spine. A left ductus arteriosus connected to the descending aorta completing the vascular ring, with notable esophageal compression. Surgical correction was accomplished through median sternotomy, resection of the hypoplastic circumflex arch, aortic arch advancement, and end-to-side anastomosis.

IL-17 producing CD4 T cells (Th17) cells increase significantly with disease severity in myasthenia gravis (MG) patients. To suppress the generation of Th17 cells, we examined the effect of inhibiting retinoic acid receptor-related-orphan-receptor-C (RORγ), a Th17-specific transcription factor critical for differentiation. RORγ inhibition profoundly reduced Th17 cell frequencies, including IFN-γ and IL-17 co-producing pathogenic Th17 cells. Other T helper subsets were not affected. In parallel, CD8 T cell subsets producing IL-17 and IL-17/IFN-γ were increased in MG patients and inhibited by the RORγ inhibitor. These findings provide rationale for exploration of targeted Th17 therapies, including ROR-γ inhibitors, to treat MG patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest., (Copyright © 2019 Elsevier Inc. All rights reserved.)

While signs and symptoms of peripheral neuropathy may appear to be similar among all patients, further evaluation both at the bedside and beyond demonstrate distinct differences in the pattern of certain neuropathies. A working knowledge of these differences and of the available tools to distinguish them is quite useful to the clinician. This chapter provides an overview of the distinction among various neuropathy profiles. Focal neuropathies may occur from compression or from entrapment. Neurologic examination aids in anatomic localization, which further refines and directs electrodiagnostic and ultrasound testing. Subsequent therapeutic approaches vary depending on the location of the focal neuropathy. Focal neuropathy may occur outside of pregnancy but the outcome is more predictable in this situation., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Our objective is to report longitudinal results of the MG-ADL, MG-Composite, MG-MMT, and MG-QoL15 in an open-label trial of therapeutic plasma exchange in myasthenia gravis. Ten MG patients experiencing exacerbation had assessments prior to, immediately following, and at selected time points post-TPE. Changes from baseline to 2 weeks post-TPE were: MG-ADL median -5.0, P < 0.0033, MG-QoL15 median -13.0, P < 0.001, MG-MMT median -10.0, P < 0.0001, and MG-Composite median -10.0, P < 0.005. TPE produced a rapid, clinically significant change in all instruments, indicating these outcome measures are robust endpoints for clinical trials of rapidly efficacious MG therapies., (© 2019 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.)

Background: The Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone (MGTX) showed that thymectomy combined with prednisone was superior to prednisone alone in improving clinical status as measured by the Quantitative Myasthenia Gravis (QMG) score in patients with generalised non-thymomatous myasthenia gravis at 3 years. We investigated the long-term effects of thymectomy up to 5 years on clinical status, medication requirements, and adverse events., Methods: We did a rater-blinded 2-year extension study at 36 centres in 15 countries for all patients who completed the randomised controlled MGTX and were willing to participate. MGTX patients were aged 18 to 65 years at enrolment, had generalised non-thymomatous myasthenia gravis of less than 5 years' duration, had acetylcholine receptor antibody titres of 1·00 nmol/L or higher (or concentrations of 0·50-0·99 nmol/L if diagnosis was confirmed by positive edrophonium or abnormal repetitive nerve stimulation, or abnormal single fibre electromyography), had Myasthenia Gravis Foundation of America Clinical Classification Class II-IV disease, and were on optimal anticholinesterase therapy with or without oral corticosteroids. In MGTX, patients were randomly assigned (1:1) to either thymectomy plus prednisone or prednisone alone. All patients in both groups received oral prednisone at doses titrated up to 100 mg on alternate days until they achieved minimal manifestation status. The primary endpoints of the extension phase were the time-weighted means of the QMG score and alternate-day prednisone dose from month 0 to month 60. Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00294658. It is closed to new participants, with follow-up completed., Findings: Of the 111 patients who completed the 3-year MGTX, 68 (61%) entered the extension study between Sept 1, 2009, and Aug 26, 2015 (33 in the prednisone alone group and 35 in the prednisone plus thymectomy group). 50 (74%) patients completed the 60-month assessment, 24 in the prednisone alone group and 26 in the prednisone plus thymectomy group. At 5 years, patients in the thymectomy plus prednisone group had significantly lower time-weighted mean QMG scores (5·47 [SD 3·87] vs 9·34 [5·08]; p=0·0007) and mean alternate-day prednisone doses (24 mg [SD 21] vs 48 mg [29]; p=0·0002) than did those in the prednisone alone group. 14 (42%) of 33 patients in the prednisone group, and 12 (34%) of 35 in the thymectomy plus prednisone group, had at least one adverse event by month 60. No treatment-related deaths were reported during the extension phase., Interpretation: At 5 years, thymectomy plus prednisone continues to confer benefits in patients with generalised non-thymomatous myasthenia gravis compared with prednisone alone. Although caution is appropriate when generalising our findings because of the small sample size of our study, they nevertheless provide further support for the benefits of thymectomy in patients with generalised non-thymomatous myasthenia gravis., Funding: National Institutes of Health, National Institute of Neurological Disorders and Stroke., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Muscle specific tyrosine kinase antibody positive myasthenia gravis (MuSK- MG) is characterized by autoantibodies against the MuSK protein of the neuromuscular junction resulting in weakness of bulbar and proximal muscles. We previously demonstrated that patients with MuSK-MG have increased pro-inflammatory Th1 and Th17 responses. Tacrolimus, an immunosuppressant used in AChR-MG and transplantation patients, inhibits T cell responses through interference with IL-2 transcription. The therapeutic efficacy and immunological effect of tacrolimus in MuSK-MG is unclear. In the current study we examined the proliferation, phenotype and cytokine production of CD4+ and CD8+ T cells in peripheral blood mononuclear cells of MuSK-MG following a 3-day in vitro culture with or without tacrolimus. We determined that tacrolimus profoundly suppressed CD4 and CD8 T cell proliferation and significantly suppressed Th1 and Th17 responses, as demonstrated by a reduced frequency of IFN-γ, IL-2, and IL-17 producing CD4 T cells and reduced frequencies of IFN-γ and IL-2 producing CD8 T cells. Tacrolimus also inhibits pathogenic Th17 cells coproducing IL-17 and IFN-γ. In addition, tacrolimus suppressed follicular T helper cell (Tfh) and regulatory T helper cell (Treg) subsets. These findings provide preliminary support for tacrolimus as a potential alternative immunosuppressive therapy for MuSK-MG., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Muscle-specific tyrosine kinase antibody positive myasthenia gravis (MuSK+ MG) is an immunological subtype with distinctive pathogenic mechanisms and clinical features. The aim of this study was to analyze the circulating plasma microRNA profile of patients with MuSK+ MG. From the discovery cohort miR-210-3p, miR-324-3p and miR-328-3p were further analyzed in the validation cohort. We found a distinct plasma profile of miR-210-3p and miR-324-3p that were significantly decreased in MuSK+ MG patients compared to healthy controls (4.1 ± 1.4 vs 5.1 ± 1.4, p = .006 and 4.7 ± 1.0 vs 5.4 ± 1.3, p = .02). These findings reveal a distinct plasma miRNA profile in MuSK+ MG., (Copyright © 2018 Elsevier B.V. All rights reserved.)

African Americans are disproportionately impacted by homicide in the United States. Individuals who have lost a relative to homicide often experience symptoms of complicated grief. The objective of this study was to explore the impact of a culturally tailored psychoeducational pilot intervention whose development was informed by a conceptual model of coping for African American survivors of homicide victims and was designed to (a) educate participants about the manifestation of complicated grief and symptoms and (b) help participants develop ways to cope with their grief. Pre- and post-test results indicate preliminary support for this encouraging intervention in achieving its intended outcomes to help participants identify complicated grief symptoms, supports, and services to help them manage their grief. Implications for posthomicide research and practice are discussed., (© 2018 Springer Publishing Company, LLC.)

Introduction: We report the reliability of a new measure, the triple-timed up-and-go (3TUG) test, for assessing clinical function in patients with Lambert-Eaton myasthenia (LEM)., Methods: Intrarater reproducibility and interrater agreement of the 3TUG test were assessed in 25 control participants, 24 patients with non-LEM neuromuscular disease, and 12 patients with LEM. The coverage probability (CP) method was the primary measure of reproducibility and agreement. The a priori acceptable range was < 20% difference in 3TUG test times and a CP ≥0.90 confirmed agreement., Results: CP values > 0.90 for intrarater and interrater tests confirmed acceptable reproducibility and agreement for all groups., Discussion: The 3TUG test is a quick, noninvasive, and reproducible measure that is easy to perform, measures clinically important weakness in LEM patients, and requires little training. Additional evaluation in a larger number of LEM patients is in progress to validate the 3TUG test as a clinical measure in LEM. Muscle Nerve 57: 136-139, 2017., (© 2017 Wiley Periodicals, Inc.)

Introduction: The objective of this study was to determine if single-fiber electromyography (SFEMG) jitter accurately reflects change in severity in myasthenia gravis (MG)., Methods: We reviewed jitter and outcome data from all MG patients in our clinic who had at least 2 jitter measurements in the extensor digitorum or frontalis muscle., Results: Change in all parameters of jitter measured with SFEMG electrodes predicted clinical change with acceptable accuracy. Absolute and percentage change in mean value of consecutive interval differences were equally accurate in predicting clinical change and were more accurate than change in the proportion of fiber pairs with blocking or normal jitter., Conclusions: Jitter is a sensitive measure of severity in MG and has a potential role as a biomarker in clinical trials and the clinic. Absolute or percentage change in mean jitter is the best jitter parameter to follow. The accuracy of change in jitter measured with other electrodes has yet to be determined. Muscle Nerve 56: 45-50, 2017., (© 2016 Wiley Periodicals, Inc.)

Background: Missing a fracture in a child on skeletal surveys for suspected non-accidental trauma can have devastating results. Double-read has the potential to improve fracture detection. However the yield of double-read is unknown., Objective: To determine the advantage of double-read versus single-read of radiographic skeletal surveys for suspected non-accidental trauma., Materials and Methods: The study was performed in two phases. In the first phase (April 2013 to September 2013), double-read was performed for all skeletal surveys obtained during weekday working hours. Because we had no new double-read findings in studies initially read as negative, we conducted a second phase (January 2014 to March 2014). In the second phase we limited double-reads to skeletal surveys found positive on the first read. At the end of this period, we retrospectively performed double-read for all initially negative skeletal surveys. We excluded follow-up skeletal surveys. The difference in discrepancy (new fracture or false diagnosis of a fracture) ratio between negative and positive skeletal surveys was evaluated using the Fisher exact test, and change in discrepancy ratio between the first and second study phases was evaluated using the stratified Cochran-Mantel-Haenszel test., Results: Overall in the two phases, 178 skeletal surveys were performed in 178 children (67 girls) with mean age of 9 months (range 3 days to 3.7 years). Double-read found 16 discrepancies in 8/178 (4.5%) skeletal surveys. Seven of these studies showed additional fractures (n=15). In one study, an initial read of a skull fracture was read as a variant on the second read. There was a significant (P=0.01) difference between rate of disagreement in negative skeletal surveys (1/104, 1.0%) and positive skeletal surveys (7/74, 9.5%). No significant change in disagreement rate was demonstrated between the two phases of the study (P=0.59)., Conclusion: Double-read of skeletal survey for suspected non-accidental trauma found false-negative fractures in a few cases and rarely found false-positive diagnosis of a fracture. Double-read uncommonly found discrepancies in an initially normal skeletal survey. Limiting double-read to initially positive studies improves the yield of the double-read.

Myasthenia gravis (MG) is a T cell-dependent, B cell-mediated disease. The mechanisms for loss of self-tolerance in this disease are not well understood, and recently described regulatory B cell (Breg) subsets have not been thoroughly investigated. B10 cells are a subset of Bregs identified by the production of the immunosuppressive cytokine, interleukin-10 (IL-10). B10 cells are known to strongly inhibit B- and T-cell inflammatory responses in animal models and are implicated in human autoimmunity. In this study, we examined quantitative and qualitative aspects of B10 cells in acetylcholine receptor autoantibody positive MG (AChR-MG) patients and healthy controls. We observed reduced B10 cell frequencies in AChR-MG patients, which inversely correlated with disease severity. Disease severity also affected the function of B10 cells, as B10 cells in the moderate/severe group of MG patients were less effective in suppressing CD4 T-cell proliferation. These results suggest that B10 cell frequencies may be a useful biomarker of disease severity, and therapeutics designed to restore B10 cell frequencies could hold promise as a treatment for this disease through restoration of self-tolerance.

An integrated understanding of therapeutic plasma exchange (TPE) effects on immunoglobulins, autoantibodies, and natural or acquired (vaccine) protective antibodies in patients with autoimmune myasthenia gravis (MG) is lacking. Prior studies measured TPE effects in healthy volunteers or heterogeneous autoimmune disease populations. We prospectively profiled plasma IgA, IgM, IgG, IgG subclasses (IgG1-4), acetylcholine receptor autoantibodies (AChR+), and protective antibodies in patients with AChR + MG receiving TPE for an exacerbation. TPE was performed according to institutional practice and patients were profiled for up to 12 weeks. Ten patients were enrolled (median age = 72.9 years; baseline MG-Composite = 21; median TPE treatments = 6 during their first course) and all improved. The maximum decrease in all immunoglobulins, including AChR autoantibodies, was achieved on the final day of the first TPE course (∼60-70% reduction). Three weeks post-TPE, mean AChR autoantibody, total IgG, IgG1, and IgG2 titers were below the reference range and had not recovered within 20% of baseline, whereas other measured immunoglobulins approached baseline values. We did not generally observe an "overshoot" of immunoglobulins above pre-TPE levels or accelerated recovery of pathologic AChR autoantibodies. Protective antibody profiles showed similar patterns as other IgGs and were detectable at levels associated with protection from infection. A slow return to baseline for IgGs (except IgG3) was observed, and we did not observe any obvious effect of concomitant medications on this recovery. Collectively, these findings enhance our understanding of the immunological effects of TPE and further support the concept of rapid immunoglobulin depletion for the treatment of patients with MG.

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 consensus guidance statements. Definitions were developed for goals of treatment, minimal manifestations, remission, ocular MG, impending crisis, crisis, and refractory MG. An in-person panel meeting then determined 7 treatment topics to be addressed. Initial guidance statements were developed from literature summaries. Three rounds of anonymous e-mail votes were used to attain consensus on guidance statements modified on the basis of panel input., Results: Guidance statements were developed for symptomatic and immunosuppressive treatments, IV immunoglobulin and plasma exchange, management of impending and manifest myasthenic crisis, thymectomy, juvenile MG, MG associated with antibodies to muscle-specific tyrosine kinase, and MG in pregnancy., Conclusion: This is an international formal consensus of MG experts intended to be a guide for clinicians caring for patients with MG worldwide., (© 2016 American Academy of Neurology.)

Lambert-Eaton myasthenic syndrome (LEMS) and botulism are acquired presynaptic nerve terminal disorders of the neuromuscular junction. Lambert-Eaton myasthenic syndrome is an idiopathic or paraneoplastic autoimmune syndrome in which autoantibodies of the P/Q-type voltage-gated calcium channel play a role in decreasing the release of acetylcholine, resulting in clinical symptoms of skeletal muscle weakness, diminished reflexes, and autonomic symptoms. Paraneoplastic LEMS is most often associated with small cell lung cancer. Diagnosis is confirmed by positive serologic testing and electrophysiological studies, which display characteristic features of low compound muscle action potentials, a decrement at 3Hz repetitive nerve stimulation, and facilitation with exercise or high-frequency repetitive stimulation. Treatment involves cancer monitoring and treatment, 3,4-diaminopyridine, immunosuppressive medications, and acetylcholinesterase inhibitors. Botulism is another presynaptic disorder of neuromuscular transmission. Clinical features classically involve cranial and bulbar palsies followed by descending weakness of the limbs, respiratory failure, and autonomic dysfunction. Electrodiagnostic testing is important in the evaluation and diagnosis. Treatment is supportive, and administration of antitoxin is beneficial in selected cases., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Importance: Myasthenia gravis is a chronic, autoimmune, neuromuscular disease characterized by fluctuating weakness of voluntary muscle groups. Although genetic factors are known to play a role in this neuroimmunological condition, the genetic etiology underlying myasthenia gravis is not well understood., Objective: To identify genetic variants that alter susceptibility to myasthenia gravis, we performed a genome-wide association study., Design, Setting, and Participants: DNA was obtained from 1032 white individuals from North America diagnosed as having acetylcholine receptor antibody-positive myasthenia gravis and 1998 race/ethnicity-matched control individuals from January 2010 to January 2011. These samples were genotyped on Illumina OmniExpress single-nucleotide polymorphism arrays. An independent cohort of 423 Italian cases and 467 Italian control individuals were used for replication., Main Outcomes and Measures: We calculated P values for association between 8,114,394 genotyped and imputed variants across the genome and risk for developing myasthenia gravis using logistic regression modeling. A threshold P value of 5.0×10(-8) was set for genome-wide significance after Bonferroni correction for multiple testing., Results: In the overall case-control cohort, we identified association signals at CTLA4 (rs231770; P=3.98×10(-8); odds ratio, 1.37; 95% CI, 1.25-1.49), HLA-DQA1 (rs9271871; P=1.08×10(-8); odds ratio, 2.31; 95% CI, 2.02-2.60), and TNFRSF11A (rs4263037; P=1.60×10(-9); odds ratio, 1.41; 95% CI, 1.29-1.53). These findings replicated for CTLA4 and HLA-DQA1 in an independent cohort of Italian cases and control individuals. Further analysis revealed distinct, but overlapping, disease-associated loci for early- and late-onset forms of myasthenia gravis. In the late-onset cases, we identified 2 association peaks: one was located in TNFRSF11A (rs4263037; P=1.32×10(-12); odds ratio, 1.56; 95% CI, 1.44-1.68) and the other was detected in the major histocompatibility complex on chromosome 6p21 (HLA-DQA1; rs9271871; P=7.02×10(-18); odds ratio, 4.27; 95% CI, 3.92-4.62). Association within the major histocompatibility complex region was also observed in early-onset cases (HLA-DQA1; rs601006; P=2.52×10(-11); odds ratio, 4.0; 95% CI, 3.57-4.43), although the set of single-nucleotide polymorphisms was different from that implicated among late-onset cases., Conclusions and Relevance: Our genetic data provide insights into aberrant cellular mechanisms responsible for this prototypical autoimmune disorder. They also suggest that clinical trials of immunomodulatory drugs related to CTLA4 and that are already Food and Drug Administration approved as therapies for other autoimmune diseases could be considered for patients with refractory disease.

Objective: To characterize B-cell subsets in patients with muscle-specific tyrosine kinase (MuSK) myasthenia gravis (MG)., Methods: In accordance with Human Immunology Project Consortium guidelines, we performed polychromatic flow cytometry and ELISA assays in peripheral blood samples from 18 patients with MuSK MG and 9 healthy controls. To complement a B-cell phenotype assay that evaluated maturational subsets, we measured B10 cell percentages, plasma B cell-activating factor (BAFF) levels, and MuSK antibody titers. Immunologic variables were compared with healthy controls and clinical outcome measures., Results: As expected, patients treated with rituximab had high percentages of transitional B cells and plasmablasts and thus were excluded from subsequent analysis. The remaining patients with MuSK MG and controls had similar percentages of total B cells and naïve, memory, isotype-switched, plasmablast, and transitional B-cell subsets. However, patients with MuSK MG had higher BAFF levels and lower percentages of B10 cells. In addition, we observed an increase in MuSK antibody levels with more severe disease., Conclusions: We found prominent B-cell pathology in the distinct form of MG with MuSK autoantibodies. Increased BAFF levels have been described in other autoimmune diseases, including acetylcholine receptor antibody-positive MG. This finding suggests a role for BAFF in the survival of B cells in MuSK MG, which has important therapeutic implications. B10 cells, a recently described rare regulatory B-cell subset that potently blocks Th1 and Th17 responses, were reduced, which suggests a potential mechanism for the breakdown in immune tolerance in patients with MuSK MG.