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Continuum Postreading Test 28(6) December 2022 (Muscle and Neuromuscular Junction Disorders)

Continuum Postreading Test 28(6) December 2022 (Muscle and Neuromuscular Junction Disorders)

Learning Objectives

Upon completion of this Continuum: Lifelong Learning in Neurology Muscle and Neuromuscular
Junction Disorders issue, participants will be able to:
◆ Describe the symptoms and signs used to direct the diagnostic evaluation of patients presenting with muscle weakness
◆ Describe the clinical features, diagnosis, and management of Lambert-Eaton myasthenic syndrome and botulism, presynaptic disorders of neuromuscular transmission in which rapid diagnosis improves long-term outcome
◆ Describe the current diagnostic and treatment strategies for various subtypes of myasthenia gravis
◆ Describe the key clinical features, diagnostic testing, differential diagnosis, and the approach to treatment of the idiopathic inflammatory myopathies
◆ Discuss the salient clinical features, diagnostic tools, pathogenic mechanisms, and management recommendations of inclusion body myositis
◆ Discuss the epidemiology, genetics, clinical presentation, multidisciplinary management, and therapies for the dystrophinopathies
◆ Discuss the clinical and genetic classification scheme and management of patients with limb-girdle muscular dystrophies
◆ Describe the basic principles of the genetics and pathomechanism of myotonic dystrophy, and recognize, diagnose, monitor, and manage symptoms and signs of both types of myotonic dystrophy
◆ Diagnose and manage patients with facioscapulohumeral muscular dystrophy
◆ Describe the biochemical and clinical features of and treatment options for the more common metabolic myopathies
◆ Describe the clinical presentation, diagnosis, and treatment strategies of muscle channelopathies
◆ Identify ideal gene therapy strategies for specific disease mechanisms in muscular dystrophies and congenital myopathies
◆ List the steps involved in the drug approval process, identify the role of experimental neurotherapeutics in the clinic, and describe how to engage in clinical trials

Core Competencies

This Continuum: Lifelong Learning in Neurology Muscle and Neuromuscular Junction Disorders issue covers the following core competencies:
◆ Patient Care and Procedural Skills
◆ Medical Knowledge
◆ Practice-Based Learning and Improvement
◆ Interpersonal and Communication Skills
◆ Professionalism
◆ Systems-Based Practice

Contributorsa

Michael K. Hehir II, MD, Guest Editor
Associate Professor of Neurological Sciences; Division Chief of Neuromuscular Medicine, University of Vermont Larner College of Medicine and the University of Vermont Medical Center, Burlington, Vermont

Relationship Disclosure: Dr Hehir has received personal compensation in the range of $500 to $4999 for serving as a consultant for Janssen and UCB Pharma; in the range of $5000 to $9999 for serving as a consultant for argenx; and in the range of $10,000 to $49,999 for serving as a consultant for Alexion Pharmaceuticals.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Hehir discusses the unlabeled/investigational use of azathioprine, orticosteroids, cyclophosphamide, cyclosporine, intravenous immunoglobulin, methotrexate, mycophenolate mofetil, plasma exchange, and tacrolimus for the treatment of myasthenia gravis.

Andrew R. Findlay, MD
Assistant Professor of Neurology, Department of Neurology, Neuromuscular Section, Washington University School of Medicine, St. Louis, Missouri

Relationship Disclosure: Dr Findlay has received personal compensation in the range of $500 to $4999 for serving as a consultant for Atheneum, Guidepoint, RiverVest, and Triangle Insights Group. The institution of Dr Findlay has received research support from the American Academy of Neurology, the American Society for Gene and Cell Therapy, The LGMD-1D DNAJB6 Foundation and International Registry, the National Institutes of Health, and the Children's Discovery Institute of Washington University and St. Louis Children's Hospital.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Findlay reports no disclosure.

Namita A. Goyal, MD, FAAN
Professor of Neurology; Co-Director, MDA ALS and Neuromuscular Center; Director, Neuromuscular Medicine Fellowship; Director, ALS Clinic, University of California, Irvine, Irvine, California

Relationship Disclosure: Dr Goyal has received personal compensation in the range of $500 to $4999 for serving on a scientific advisory or data safety monitoring boards or on a speakers bureau for Abcuro, Alexion Pharmaceuticals, Annexon, argenx, AstraZeneca, CSL Behring, Kezar Life Sciences, Sanofi, and UCB. The institution of Dr Goyal has received research support from Alexion Pharmaceuticals, Amylyx, Anelixis Pharmaceuticals, Annexon, BrainStorm Cell Therapeutics, Cytokinetics, Fulcrum Therapeutics, the HEALEY ALS Platform Trial, Kezar Life Sciences, MediciNova, Mitsubishi Tanabe Pharma, and Transposon Therapeutics. Dr Goyal has received publishing royalties from a publication relating to health care.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Goyal reports no disclosure.

Robert C. Griggs, MD, FAAN
Professor of Neurology, Medicine, Pathology and Laboratory Medicine, Pediatrics, and the Center for Health + Technology, University of Rochester Medical Center, Rochester, New York

Relationship Disclosure: Dr Griggs has received personal compensation in the range of $0 to $499 for serving on a scientific advisory or data safety monitoring board for Santhera Pharmaceuticals; in the range of $500 to $4999 for serving on a scientific advisory or data safety monitoring board for Idera, as an editor, associate editor, or editorial advisory board member for Lippincott, and as a study section member with the National Institutes of Health; in the range of $5000 to $9999 for serving as a consultant for Xeris Pharmaceuticals, Inc and on a data safety monitoring board for Solid Biosciences Inc; and in the range of $10,000 to $49,999 for serving as an editor, associate editor, or editorial advisory board member for Elsevier. Dr Griggs has a noncompensated relationship as a member of the board of directors with the American Brain Foundation. The institution of Dr Griggs has received research support from the National Institutes of Health, PTC Therapeutics, and Sarepta Therapeutics, Inc.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Griggs discusses the unlabeled/investigational use of mexiletine for myotonic dystrophy, ketogenic diet for glycogen storage disease, and the IL-6 cytokine inhibitor tocilizumab and JAK-STAT inhibitor ruxolitinib for the treatment of inflammatory myopathies.

Johanna I. Hamel, MD
Assistant Professor of Neurology, Pathology, and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York

Relationship Disclosure: Dr Hamel has received personal compensation in the range of $500 to $4999 for serving as a consultant for Vertex Pharmaceuticals.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Hamel discusses unlabeled/investigational use of mexiletine for the treatment of myotonia and modafinil for the treatment of daytime sleepiness in myotonic dystrophy.

Nicholas E. Johnson, MD, FAAN
Vice Chair of Research; Associate Professor, Department of Neurology, Virginia Commonwealth University, Richmond, Virginia

Relationship Disclosure: Dr Johnson has received personal compensation in the range of $500 to $4999 for serving as a consultant for Acceleron Pharma, Avidity Biosciences, Dyne Therapeutics, Entrada Therapeutics, Juvena Therapeutics, Sarepta Therapeutics, Triplet Therapeutics, and Vertex Pharmaceuticals and for serving on a scientific advisory or data safety monitoring board for Biogen; in the range of $10,000 to $49,999 for serving as a consultant for Arthex Biotech; and in the range of $50,000 to $99,999 for serving as a consultant for ML Bio Solutions. Dr Johnson holds stock in ML Bio Solutions and has received intellectual property interests from a discovery or technology relating to health care. The institution of Dr Johnson has received research support from AMO Pharma, Dyne Therapeutics, Entrada Therapeutics, Fulcrum Therapeutics, ML Bio Solutions, Novartis Gene Therapies, Sarepta Therapeutics, Triplet Therapeutics, and Vertex Pharmaceuticals.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Johnson reports no disclosure.

Bo Hoon Lee, MD
Assistant Professor of Neurology and Pediatrics, University of Rochester, Rochester, New York

Relationship Disclosure: Dr Lee has received personal compensation in the range of $500 to $4999 for serving on a scientific advisory or data safety monitoring board for AMO Pharma and F. Hoffmann-La Roche AG. The institution of Dr Lee has received research support from AMO Pharma, Novartis, Sanofi, and Sarepta Therapeutics.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Lee discusses the unlabeled/investigational use of allogenic cell therapy, ataluren, follistatin, gene therapy, pamrevlumab, and vamorolone for the treatment of Duchenne muscular dystrophy.

Yuebing Li, MD, PhD, FAAN
Professor of Neurology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio

Relationship Disclosure: Dr Li has received personal compensation in the range of $500 to $4999 for serving as a consultant for Catalyst Pharmaceuticals, Immunovant, and UCB Pharma and in the range of $5000 to $9999 for serving as a consultant for argenx. The institution of Dr Li has received research support from argenx.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Li discusses the unlabeled/investigational use of azathioprine, corticosteroids, cyclophosphamide, cyclosporine, intravenous immunoglobulin, methotrexate, mycophenolate mofetil, plasma exchange, and tacrolimus for the treatment of myasthenia gravis.

Georgios Manousakis, MD, FAAN
Clinical Associate Professor of Neurology, Department of Neurology, University of Minnesota, Minneapolis, Minnesota

Relationship Disclosure: Dr Manousakis has received personal compensation in the range of $500 to $4999 for serving on scientific advisory or data safety monitoring boards for Alexion Pharmaceuticals, Inc, argenx, and Stealth BioTherapeutics Inc. The institution of Dr Manousakis has received research support from the Greg Marzolf Jr. Foundation.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Manousakis discusses the unlabeled/investigational use of several immunosuppressive agents for the treatment of immune/inflammatory myopathies.

Karlien Mul, MD, PhD
Staff Clinician, Senior Researcher, Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands

Relationship Disclosure: The institution of Dr Mul has received personal compensation in the range of $500 to $4999 for serving as a consultant for Avidity Biosciences.

Avindra Nath, MD, MBBS, FAAN
Chief, Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland

Relationship Disclosure: Dr Nath has received personal compensation in the range of $10,000 to $49,999 for serving as an editor, associate editor, or editorial advisory board member for Elsevier. Dr Nath is the clinical director at the National institute for Neurological Disorders and Stroke (NINDS) and his research is supported by the ALS Association, NINDS, and the Office of AIDS Research at the National Institutes of Health.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Nath discusses the unlabeled/investigational use of mexiletine for myotonic dystrophy, ketogenic diet for glycogen storage disease, and IL-6 cytokine inhibitor tocilizumab and JAK-STAT inhibitor ruxolitinib for the treatment of inflammatory myopathies.

Shruti M. Raja, MD
Assistant Professor of Neurology, Duke University School of Medicine, Durham, North Carolina

Relationship Disclosure: Dr Raja has received personal compensation in the range of $500 to $4999 for serving as a consultant for Regeneron Pharmaceuticals and Signant Health. The institution of Dr Raja has received research support from the American Brain Foundation/Myasthenia Gravis Foundation of America.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Raja discusses the unlabeled/investigational use of immunomodulatory and immunosuppressant therapies for the treatment of Lambert-Eaton myasthenic syndrome and monoclonal antibodies for the treatment of botulism.

Lauren B. Reoma, MD, FAAN
Director, NINDS Clinical Trials Unit; Staff Clinician, Neurovirology and Neuroimmunology, Clinical Trials Unit Office of the Clinical Director, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland

Relationship Disclosure: Dr Reoma has a noncompensated relationship as a Vice Chair of the American Academy of Neurology’s Experimental Neurotherapeutics Section and is the intramural National Institute of Neurological Disorders and Stroke (NINDS) program director for the NINDS-US Food and Drug Administration (FDA) fellowship in clinical trial methodology and regulatory science.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Reoma discusses the unlabeled/investigational use of mexiletine for myotonic dystrophy, ketogenic diet for glycogen storage disease, and IL-6 cytokine inhibitor tocilizumab and JAK-STAT inhibitor ruxolitinib for the treatment of inflamatory myopathies.

Nicholas J. Silvestri, MD, FAAN
Assistant Dean for Student and Academic Affairs, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York

Relationship Disclosure: Dr Silvestri has received personal compensation in the range of $500 to $4999 for serving on a scientific advisory or data safety monitoring board or on a speakers bureau for Alexion Pharmaceuticals, argenx, Immunovant, Inc., Regeneron Pharmaceuticals, Sarepta Therapeutics, UCB, and Xeris Pharmaceuticals. Dr Silvestri has received publishing royalties from a publication relating to health care.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Silvestri reports no disclosure.

Jeffrey M. Statland, MD
Professor of Neurology, University of Kansas Medical Center, Kansas City, Kansas

Relationship Disclosure: Dr Statland has received personal compensation in the range of $500 to $4999 for serving as a consultant for Arrowhead Pharmaceuticals, ML Bio Solutions, and Mitsubishi Tanabe Pharma and for serving on a scientific advisory or data safety monitoring board for Avidity Biosciences; in the range of $5000 to $9999 for serving on a scientific advisory or data safety monitoring board for Fulcrum Therapeutics; and in the range of $10,000 to $49,999 for serving on a scientific advisory or data safety monitoring board for Dyne Therapeutics. The institution of Dr Statland has received research support from Friends of FSH Research, FSHD Canada, FSHD Society, the Muscular Dystrophy Association, and the National Institutes of Health.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Statland reports no disclosure.

Mark A. Tarnopolsky, MD, PhD, FRCP
Professor of Pediatrics, McMaster University, McMaster Children's Hospital, Hamilton, Ontario, Canada

Relationship Disclosure: Dr Tarnopolsky has received personal compensation in the range of $500 to $4999 for serving as a consultant for Alexion Pharmaceuticals, for serving on a scientific advisory or data safety monitoring board for Reneo Pharmaceuticals, and for serving on a speakers bureau for Sanofi; in the range of $5000 to $9999 for serving as a consultant for Sanofi ; and in the range of $10,000 to $49,999 for serving as a consultant for Reneo Pharmaceuticals. Dr Tarnopolsky has stock in Synaptive Medical. Dr Tarnopolsky has stock in Cloud DX. The institution of Dr Tarnopolsky has received research support from the Canadian Institutes of Health Research. Dr Tarnopolsky has received intellectual property interests from a discovery or technology relating to health care.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Tarnopolsky reports no disclosure.

Jaya R. Trivedi, MD, FAAN
Professor of Neurology, University of Texas Southwestern Medical Center, Dallas, Texas

Relationship Disclosure: Dr Trivedi has received personal compensation in the range of $500 to $4999 for serving on a scientific advisory or data safety monitoring board for argenx. The institution of Dr Trivedi has received research support from the National Institutes of Health.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Trivedi discusses the unlabeled use of acetazolamide for the treatment of glaucoma; carbamazepine, lacosamide, lamotrigine, phenytoin, and rufinamide for the treatment of epilepsy; eplerenone, hydrochlorothiazide, spironolactone, and triamterene for the treatment of hypertension; flecainide, mexiletine, procainamide, quinine, and tocainide for the treatment of cardiac arrhythmias; ranolazine for the treatment of angina; and quinine for the treatment of malaria.

Conrad C. Weihl, MD, PhD
Professor of Neurology; Chief of Neuromuscular Section, Washington University School of Medicine, St. Louis, Missouri

Relationship Disclosure: Dr Weihl has received personal compensation in the range of $500 to $4999 for serving as a consultant or on a scientific advisory or data safety monitoring board for Abata Therapeutics, Acceleron Pharma, Casma Therapeutics, and Sarepta Therapeutics.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Weihl reports no disclosure.

Self-Assessment and CME Test Writers

James W. M. Owens Jr, MD, PhD
Associate Professor of Neurology; Adjunct Associate Professor of Pediatrics, University of Washington School of Medicine, Seattle, Washington

Relationship Disclosure: Dr Owens has received personal compensation in the range of $500 to $4999 for serving as an Associate Editor for Continuing Medical Education and as a question writer for the American Academy of Neurology. Dr Owens has a noncompensated relationship as a member of the Accreditation Council with the United Council for Neurologic Subspecialties.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Owens reports no disclosure.

Allyson R. Zazulia, MD
Professor of Neurology and Radiology and Associate Dean for Continuing Medical Education, Washington University, St. Louis, Missouri

Relationship Disclosure: Dr Zazulia reports no disclosure.

Unlabeled Use of Products/Investigational Use Disclosure: Dr Zazulia reports no disclosure.

AAll relevant financial relationships have been mitigated.

Accreditation

Accreditation Statement: The American Academy of Neurology Institute is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide CME for physicians. For information on Continuum Audio CME, please visitcontinuum.audio-digest.org.

AMA Credit: The American Academy of Neurology Institute designates this enduring material for a maximum of 20 AMA PRA Category1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

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Continuum: Lifelong Learning in Neurology® is designed to help practicing neurologists stay abreast of advances in the field while simultaneously developing lifelong self-directed learning skills. In Continuum, the process of absorbing, integrating, and applying the material presented is as important as, if not more important than, the material itself.

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