Seminars in Neurology最新文献

Vasculitic neuropathies are a diverse group of inflammatory polyneuropathies that result from systemic vasculitis (e.g., polyarteritis nodosa, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, microscopic polyangiitis), vasculitis resulting from rheumatological disorders (e.g., rheumatoid arthritis and Sjögren's syndrome), paraneoplastic conditions, viruses, and medications. Occasionally, vasculitis is restricted to the peripheral nerves and termed nonsystemic vasculitic neuropathy. Presenting with an acute or subacute onset of painful sensory and motor deficits, ischemia to individual peripheral nerves results in the classic "mononeuritis multiplex" pattern. Over time, overlapping mononeuropathies will result in a symmetrical or asymmetrical sensorimotor axonal polyneuropathy. The diagnosis of vasculitic neuropathies relies on extensive laboratory testing, electrodiagnostic testing, and nerve and/or other tissue biopsy. Treatment consists primarily of immunosuppressant medications such as corticosteroids, cyclophosphamide, rituximab, methotrexate, or azathioprine, in addition to neuropathic pain treatments. Frequently, other specialists such as rheumatologists, pulmonologists, and nephrologists will comanage these complex patients with systemic vasculitis. Prompt recognition of these conditions is imperative, as delays in treatment may result in permanent deficits and even death.

Disorders of the somatosensory nervous system that cause neuropathic pain are treated in a variety of ways. Herein, we introduce a stepwise approach to treating neuropathic pain. We then summarize the available data and guidelines for treating neuropathic pain, both with pharmacologic and nonpharmacologic methods, and provide a synthesized algorithm highlighting the similarities and differences between recent guidelines on the management of neuropathic pain. Pharmacologic treatments are primarily antiseizure medications (e.g., gabapentinoids, sodium channel blockers) and antidepressant medications (e.g., tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors), though other medications and interventional pharmacologic therapies can also be considered. There are a wide variety of nonpharmacologic treatments for neuropathic pain including neuromodulation, nerve stimulation, physiotherapy, movement therapies, lifestyle modification, nutritional supplements, acupuncture, and mind-body techniques.

The classification of peripheral neuropathies has traditionally been based on etiology, electrodiagnostic findings, or histopathologic features. With the advent of modern imaging, they now can also be characterized based on their varied distribution of imaging findings. We describe the major morphologic patterns of these changes, which include homogeneous enlargement; homogeneous thinning; focal, multifocal, and segmental enlargement; and focal thinning and beading (multifocal thinning). Representative disorders in each of these categories are discussed, along with examples of the more complex imaging manifestations of neuralgic amyotrophy, nerve transection, and hereditary amyloidosis. An appreciation of the diverse morphologic manifestations of neuropathy can help neuromuscular clinicians conduct appropriate imaging studies with ultrasound and, when needed, order suitable investigations with magnetic resonance neurography.

Patients undergoing solid-organ transplantation (SOT) face a tumultuous journey. Prior to transplant, their medical course is characterized by organ dysfunction, diminished quality of life, and reliance on organ support, all of which are endured in hopes of reaching the haven of organ transplantation. Peritransplant altered mental status may indicate neurologic insults acquired during transplant and may have long-lasting consequences. Even years after transplant, these patients are at heightened risk for neurologic dysfunction from a myriad of metabolic, toxic, and infectious causes. This review provides a comprehensive examination of causes, diagnostic approaches, neuroimaging findings, and management strategies for altered mental status in SOT recipients. Given their complexity and the numerous etiologies for neurologic dysfunction, liver transplant patients are a chief focus in this review; however, we also review lesser-known contributors to neurological injury across various transplant types. From hepatic encephalopathy to cerebral edema, seizures, and infections, this review highlights the importance of recognizing and managing pre- and posttransplant neurological complications to optimize patient outcomes.

Delirium and dementia are common causes of cognitive impairment in older adults. They are distinct but interrelated. Delirium, an acute confusional state, has been linked to the chronic and progressive loss of cognitive ability seen in dementia. Individuals with dementia are at higher risk for delirium, and delirium itself is a risk factor for incident dementia. Additionally, delirium in individuals with dementia can hasten underlying cognitive decline. In this review, we summarize recent literature linking these conditions, including epidemiological, clinicopathological, neuroimaging, biomarker, and experimental evidence supporting the intersection between these conditions. Strategies for evaluation and diagnosis that focus on distinguishing delirium from dementia in clinical settings and recommendations for delirium prevention interventions for patients with dementia are presented. We also discuss studies that provide evidence that delirium may be a modifiable risk factor for dementia and consider the impact of delirium prevention interventions on long-term outcomes.

Mental status is the collection of an individual's consciousness, perception, emotion, memory, and cognition at a particular point in time, which is inferred by the clinician through careful observation and interaction. The pediatric mental status assessment must be approached with an understanding of cognitive, language, and psychosocial development. Alterations must then be comprehensively and clearly described. Delirium is a phenotypic diagnosis with a specific set of criteria in the DSM and is a serious neurocognitive disorder caused by physiologic changes due to illness, injury, toxins, medications, and/or substances. Recognition of delirium in children is improved by monitoring of predisposing risks and precipitating factors, as well as the regular use of validated pediatric screening tools. Management of delirium is focused on treatment of the underlying etiology, prevention of iatrogenic deliriogenic factors, and patient safety.

Acute encephalopathy is a common presenting symptom in the emergency room and complicates many hospital and intensive care unit admissions. The evaluation of patients with encephalopathy poses several challenges: limited history and examination due to the patient's mental status, broad differential diagnosis of systemic and neurologic etiologies, low yield of neurodiagnostic testing due to the high base rate of systemic causes, and the importance of identifying less common neurologic causes of encephalopathy that can be life-threatening if not identified and treated. This article discusses the differential diagnosis of acute encephalopathy, presents an approach to the history and examination in a patient with encephalopathy, reviews the literature on the yield of neurodiagnostic testing in this population, and provides a diagnostic framework for the evaluation of patients with altered mental status.

Consultation liaison psychiatrists are frequently asked to evaluate patients with altered mental status (AMS). Psychiatrists have unique perspectives and approaches to care for confused patients, particularly optimizing facilitation of care and maintaining vigilance for diagnostic overshadowing. Psychiatrists also offer expertise in primary psychiatric illnesses that can overlap with AMS, and the most common etiology of AMS is delirium. In this article, we provide a consultation liaison psychiatrist perspective on AMS and related psychiatric conditions in addition to delirium. Manic and psychotic episodes have primary and secondary etiologies, with some symptoms that can overlap with delirium. Catatonia, neuroleptic malignant syndrome, and serotonin syndrome are potentially fatal emergencies, and require prompt index of suspicion to optimize clinical outcomes. Trauma sequelae, functional neurologic disorders, and dissociative disorders can present as puzzling cases that require psychiatric facilitation of care. Additionally, AMS is sometimes due to substance intoxication and withdrawal in the hospital. A nonstigmatizing approach to evaluation and management of delirium and AMS can ensure optimal patient care experiences and outcomes.

Altered mental status (AMS) is a syndrome posing substantial burden to patients in the intensive care unit (ICU) in both prevalence and intensity. Unfortunately, ICU patients are often diagnosed merely with syndromic labels, particularly the duo of toxic-metabolic encephalopathy (TME) and delirium. Before applying a nonspecific diagnostic label, every patient with AMS should be evaluated for specific, treatable diseases affecting the central nervous system. This review offers a structured approach to increase the probability of identifying specific causal etiologies of AMS in the critically ill. We provide tips for bedside assessment in the challenging ICU environment and review the role and yield of common neurodiagnostic procedures, including specialized bedside modalities of diagnostic utility in unstable patients. We briefly review two common etiologies of TME (uremic and septic encephalopathies), and then review a selection of high-yield toxicologic, neurologic, and infectious causes of AMS in the ICU, with an emphasis on those that require deliberate consideration as they elude routine screening. The final section lays out an approach to the various etiologies of AMS in the critically ill.