This issue of Continuum is devoted to the diagnosis and management of our patients with disorders that involve the autonomic nervous system. It has been more than 12 years since the last issue devoted to this important but often poorly understood topic. I am therefore so pleased that Dr Eduardo E. Benarroch accepted my invitation to be the guest editor of this issue, and I extend my sincere thanks to him for inviting such an outstanding team of renowned experts to contribute to this much-needed issue in the Continuum curriculum.
I would like to thank Dr Benarroch for enlisting such expert neurologic colleagues in the autonomic field to give us a “heads-up” of what we need to know as we diagnose (even with just the standard bedside tools we all have) and manage the patients who present with autonomic dysfunction…
The issue starts with the article by Dr Benarroch, who provides his overview of the physiology and pathophysiology of the autonomic nervous system, laying the groundwork for understanding the pathophysiologic issues that underlie the specific disorders that are discussed in the articles that follow. In the next article, Dr William P. Cheshire Jr extends this introduction to the rest of the issue by providing his practical approach to the autonomic history, examination, and laboratory evaluation of patients with possible autonomic nervous system disorders. Even those (many) neurologists without access to formal autonomic testing will gain so much by understanding the theory behind this testing and recognizing how much information can be gained by a careful and honed history, a penlight for the pupils, and a stethoscope to personally check for orthostatic hypotension in the clinic.
Dr Steven Vernino discusses the clinical features, diagnosis, and management of autoimmune autonomic disorders, including autoimmune autonomic ganglionopathy and the autonomic syndromes that may occur in association with other autoimmune disorders. Dr Roy Freeman then discusses the diagnosis and management of the autonomic peripheral neuropathies, including those associated with diabetes mellitus, the amyloid polyneuropathies, the inherited autonomic neuropathies, and toxic autonomic neuropathies.
In the next article, Drs Elizabeth A. Coon and Wolfgang Singer review the α-synucleinopathies, including pure autonomic failure, multiple system atrophy, dementia with Lewy bodies, and Parkinson disease, degenerative conditions that include varying degrees and manifestations of autonomic dysfunction that may be presenting features of the diseases. Dr Jeremy K. Cutsforth-Gregory then reviews the definitions, clinical features, diagnostic investigation, and management of disorders of orthostatic intolerance, including postural tachycardia syndrome and neurally mediated syncope.
Drs Coon and Cheshire review the clinical phenomenology and management of disorders of sweating, both hyperhidrosis and hypohidrosis, conditions that may be less familiar to many neurologists but can be distressing or embarrassing to patients and may be clues to significant underlying neurologic disorders. Dr Alejandro A. Rabinstein next provides an overview of the syndromes of autonomic hyperactivity, such as paroxysmal sympathetic hyperactivity and autonomic dysreflexia, that can occur as a consequence of traumatic brain injury and spinal cord injury, respectively, and the dysautonomia that can occur with peripheral nerve dysfunction, such as in Guillain-Barré syndrome.
Drs Jose-Alberto Palma and Horacio Kaufmann provide their review of the management of patients with orthostatic hypotension, emphasizing the importance of nonpharmacologic measures, including lifestyle modifications, while delineating the role and indications for the various pharmacologic options. Drs Jalesh N. Panicker and Ryuji Sakakibara then review the pathophysiology and management of lower urinary tract and bowel dysfunction in neurologic disease, symptoms that complicate the daily lives of so many of our patients with neurologic disorders and for which the neurologist can play an important role, including in collaboration with urologists or gastroenterologists. In the final review article of the issue, Drs Christopher H. Gibbons, Ningshan Wang, Jee Young Kim, Marta Campagnolo, and Roy Freeman describe the current role of skin biopsy in the evaluation of autonomic disorders and show a glimpse of a possible future role of this minimally invasive technique in the diagnosis of α-synucleinopathies.
After reading the issue and taking the Postreading Self-Assessment and CME Test written by Drs Allison L. Weathers and Allyson R. Zazulia, you may earn up to 20 AMA PRA Category 1 CreditsTM toward self-assessment CME or, for Canadian participants, a maximum of 20 hours toward the Self-Assessment Program (Section 3) of the Maintenance of Certification Program of the Royal College of Physicians and Surgeons of Canada. Additional credit can be obtained by listening to Continuum Audio interviews associated with this and other Continuum issues, available to all subscribers, and completing tests on the Continuum Audio web platform or mobile app. Continuum Audio is also accredited by the Royal College of Physicians and Surgeons of Canada.
I would like to offer my deepest appreciation to Dr Benarroch for his expert guest editorship of this important issue in our curriculum, including his great attention to critical details in each step of planning and producing such an issue. I would also like to thank Dr Benarroch for enlisting such expert neurologic colleagues in the autonomic field to give us a “heads-up” of what we need to know as we diagnose (even with just the standard bedside tools we all have) and manage the patients who present with autonomic dysfunction due to any of the myriad central or peripheral neurologic disorders that can affect the autonomic nervous system.
—STEVEN L. LEWIS, MD, FAAN