Of All the Nerve (and Anterior Horn Cell and Neuromuscular Junction)

Peripheral Nervous System Disorders p. 1183-1184 October 2014, Vol.20, No.5 doi: 10.1212/01.CON.0000455887.21922.2e
Editor’s Preface
BROWSE ARTICLES

My sincerest thanks to Drs Mauermann and Burns for so successfully taking on the task of covering the entire peripheral nervous system fromthe nerve cell body to the neuromuscular junction.

It took some nerve for me to ask Drs Michelle L. Mauermann and Ted M. Burns to guest edit a single issue that tackles just about every disorder that can affect the peripheral nervous system anywhere along its course from the nerve cell body (anterior horn cell/dorsal root ganglion) to the neuromuscular junction. (The only elements that they were off the hook for were muscle diseases, which were so thoroughly covered in a very recent issue within our current 3-year curriculum, and structural radiculopathies, which will be covered in another issue within the curriculum). Lucky for all of us, they accepted the challenge and succeeded in creating a unique and remarkable volume that will be of tremendous benefit to each of us as we diagnose and manage the multitude of disorders that can affect the peripheral nervous system from the anterior horn cell and dorsal root ganglion to the neuromuscular junction.

This issue begins at the anterior horn cell, with an article by Drs Ezgi Tiryaki and Holli A. Horak thoroughly covering not only the diagnosis and management of ALS (a disease that can affect both the lower and upper motor neurons) but also the many other disorders that can affect the lower motor neuron throughout the lifespan. Next come a variety of articles covering the many etiologies and pathophysiologic causes of peripheral neuropathy. The first article in this series is by Dr Mario A. Saporta, who provides a clear and very effective review of the clinical presentations, classification, diagnosis, and management of Charcot-Marie-Tooth disease and other inherited causes of peripheral neuropathies, including the familial amyloid polyneuropathies. Next, Drs James W. Russell and Lindsay A. Zilliox provide a very up-to-date review of the diagnosis and management of the very common, and remarkably multifaceted, peripheral neuropathic manifestations and presentations of diabetes mellitus.

Drs Mazen M. Dimachkie and David S. Saperstein next lend their expertise in thoroughly reviewing the clinical diagnosis and management of the acute, subacute, and chronic acquired immune demyelinating neuropathies—and their variants—that may present to us in the emergency department or the outpatient setting. Continuing on a similar theme, Drs Vera Bril and Hans D. Katzberg carefully review the acquired axonal neuropathies that have an immune-mediated pathogenesis, including the vasculitic neuropathies and acute motor axonal neuropathy.

Drs Michael K. Hehir II and Eric L. Logigian provide an encyclopedic review of the many peripheral nerve disorders caused by infection by microorganisms or exposure to their toxins; recognition of these potentially treatable and, in some cases, preventable infectious-disease-associated neuropathies are extremely relevant to each of us wherever we practice in the world. Drs Nathan P. Staff and Anthony J. Windebank next contribute an equally encyclopedic review of the diagnosis and management of the multitude of peripheral nerve (and neuron) disorders that can occur as a consequence of vitamin or mineral deficiencies or from exposure to various toxins or medications. Co-guest editor Dr Michelle L. Mauermann then provides her extensive review of the neuropathies that occur as a consequence of, or coincident with, disorders characterized by the presence of a serum paraprotein—disorders that are important to recognize whether the paraproteinemia is part of a benign or malignant systemic syndrome.

In case you feel you’ve gotten enough nerve by this point of the issue, the issue veers proximally for two articles to cover the plexi. This discussion of the plexi starts with a review of the brachial plexopathies by Dr Mark A. Ferrante, who offers a remarkably clear framework for understanding the anatomy of the brachial plexus (something I finally comprehend based on his exposition!), providing the underpinning for his discussion of many of the important disorders that can affect nerves at this location. Moving inferiorly, the clinical presentation and diagnosis of the various disorders that can affect the lumbosacral plexus are reviewed in detail by Drs P. James B. Dyck and Pariwat Thaisetthawatkul, including their suggestions about management.

Moving back to the peripheral nerve, Drs Srikanth Muppidi and Steven Vernino next thoroughly discuss the clinical presentation, diagnosis, and management of the many kinds of peripheral neuropathic presentations that can occur as a paraneoplastic phenomenon and, like other paraneoplastic syndromes, may even herald the diagnosis of a systemic neoplasm. Drs Valeria Iodice and Paola Sandroni next review the many etiologies of neuropathies that include significant autonomic peripheral nervous system dysfunction, whether as a primary (eg, autoimmune) autonomic neuropathic disorder or secondary to a systemic illness.

Dr Christopher H. Gibbons then presents a thorough and up-to-date review of the current state of knowledge about the pathophysiology of the small fiber neuropathies, their clinical diagnosis and evolving diagnostic tools, and management, including a discussion of the syndrome of treatment-induced neuropathy of diabetes mellitus (formerly sometimes called insulin neuritis). The final (“distal”) review article of this issue is devoted to the neuromuscular junction, in which Drs Donald B. Sanders and Jeffrey T. Guptill share their vast experience in the management of patients with autoimmune neuromuscular junction disorders and provide a very practical and clinically relevant review of the current state-of-the-art in diagnosis and management of myasthenia gravis and Lambert-Eaton myasthenic syndrome.

In this issue’s Ethical Perspectives section, CONTINUUM Associate Editor of Ethics Dr Daniel G. Larriviere, dissects both the ethical issues and the intertwining complicated legal issues involved in the recommendation (or lack thereof) for medical marijuana for a patient with a painful HIV-associated sensory neuropathy. In this issue’s Practice section, Dr A. Gordon Smith asks, carefully analyzes, and even has the courage to answer the provocative question, “Do all neuropathy patients need an EMG at least once?” Finally, Dr Lyell K. Jones Jr presents an illustrative representative and unfolding patient case as a springboard to discuss the special considerations involved in coding for patients with peripheral neuropathy.

As with every CONTINUUM issue, a number of opportunities exist for CME. If you need to earn credits specifically approved by the American Board of Psychiatry and Neurology (ABPN) for self-assessment, submit your answers to the multiple-choice questions in the Self-Assessment Pretest that were crafted by Drs Adam G. Kelly and Joseph E. Safdieh before you read the issue; review your results to better tailor your learning needs; and then complete the Postreading CME Test after reading the issue. By doing so you may earn up to 12 AMA PRA Category 1 CME CreditsTM toward self-assessment. Alternatively, you may wish to receive credits toward CME only, in which case, reading the issue and submitting the Postreading CME Test will allow you to earn up to 10 AMA PRA Category 1 CME Credits. The Patient Management Problem, crafted by Dr Kenneth C. Gorson, involves the management of a 65-year-old man presenting to the emergency department with a rapidly progressive neurologic syndrome heralded by back pain and lower extremity sensory and motor symptoms. By following this instructive case and answering multiple-choice questions corresponding to important diagnostic and therapeutic decision points along his course, you will have the opportunity to earn up to 2 AMA PRA Category 1 CME Credits.

My sincerest thanks to Drs Mauermann and Burns for so successfully taking on the task of covering the entire peripheral nervous system from the nerve cell body to the neuromuscular junction. Their indefatigability, hard work, content expertise, and editing skills, superimposed on the outstanding contributions of each of their expert contributing authors, has created a remarkable, thorough, up-to-date, and most importantly, highly clinically useful compendium of the peripheral nervous system that will be invaluable to us in our daily evaluation and management of patients with disorders involving dysfunction of the peripheral nerve anywhere from the nerve cell body to the neuromuscular junction.

—Steven L. Lewis, MD, FAAN

Editor-in-Chief

© 2014 American Academy of Neurology