Interstitial amyloidosis in sporadic inclusion body myositis.

INTRODUCTION/AIMS: Intracellular congophilic inclusions within muscle fibers, although nonspecific, are one of the pathological hallmarks of sporadic inclusion body myositis (sIBM). Extracellular amyloid deposits in muscle, on the other hand, are the canonical findings of amyloid myopathies, which occur with or without systemic amyloidosis. METHODS: We reviewed the muscle biopsy database (1998-2020) to identify sIBM patients with extracellular amyloid deposits. Clinical and laboratory data were reviewed. RESULTS: We identified five sIBM patients (three clinicopathologically defined and two clinically defined) with extracellular amyloid deposits in muscle. Mean age at diagnosis was 74.8 y (range, 68-84 y). All patients had a typical sIBM pattern of weakness without associated sensory or autonomic symptoms. None had electrophysiological evidence of peripheral neuropathy. Only one patient had a monoclonal gammopathy (immunoglobulin M-lambda, IgM-λ) with normal bone marrow biopsy. This patient with monoclonal gammopathy and three other patients underwent abdominal fat pad aspirate and were negative for amyloid. Cardiac evaluation was unrevealing in the four patients tested. Three patients without monoclonal gammopathy had normal transthyretin gene sequencing and inconclusive mass spectrometry-based analysis. The patient with monoclonal gammopathy died of pneumosepsis 5 y after diagnosis and autopsy revealed multi-organ transthyretin amyloidosis. DISCUSSION: Detection of extracellular amyloid deposition in muscle should trigger an aggressive search for systemic amyloidosis independently from other associated myopathological abnormalities. Amyloid subtyping is crucial for early therapy and mortality prevention. An isolated monoclonal gammopathy should not halt a search for non-hematological causes of systemic amyloidosis.

Assessment in Neurologic Education.

Neurology trainee assessment is a required component of the education feedback loop, allowing programs and trainees to measure their progress toward established educational goals. In the era of competency-based medical education, assessment systems should be designed to inform decisions about each trainee's acquisition of the many competencies required for independent clinical neurology practice. In addition to the need to inform trainees and programs regarding trainee performance, assessment systems must be equipped to satisfy requirements established by accrediting bodies. Educational goals should be thoughtfully established prior to assessment system design to ensure that assessment priorities align with the overall goal of equipping graduates to deliver high-quality neurologic care. This article provides an overview of modern principles of medical education as they can be applied to neurologic education, complemented by practical recommendations for neurologic educators to develop or improve assessment systems within their own training programs.

The value transformation of health care: Impact on neuromuscular and electrodiagnostic medicine.

Beginning in 2017, most physicians who participate in Medicare are subject to the Medicare Access and CHIP Reauthorization Act (MACRA), the milestone legislation that signals the US health care system's transition from volume-based to value-based care. Here we review emerging trends in development of value-based healthcare systems in the US. MACRA and the resulting Quality Payment Program create 2 participation pathways, the Merit-based Incentive Payment System (MIPS) and the Advanced Alternative Payment Model (AAPM) pathway. Although there are several program incentives for AAPM participation, to date there have been few AAPM options for specialists. MIPS and its widening bonus and penalty window will likely be the primary participation pathway in the early years of the program. Value-based payment has the potential to reshape health care delivery in the United States, with implications for neuromuscular and electrodiagnostic (EDX) specialists. Meaningful quality measures are required for neuromuscular and EDX specialists. Muscle Nerve 56: 679-683, 2017.

Clinical spectrum of valosin containing protein (VCP)-opathy.

INTRODUCTION: Valosin containing protein (VCP) mutations cause a rare disorder characterized by hereditary inclusion body myopathy, Paget disease of bone (PDB), and frontotemporal dementia (FTD) with variable penetrance. VCP mutations have also been linked to amyotrophic lateral sclerosis and Charcot-Marie-Tooth disease type 2. METHODS: Review of clinical, serological, electrophysiological, and myopathological findings of 6 VCP-opathy patients from 4 unrelated families. RESULTS: Patients manifested muscle weakness between ages 40 and 53 years and developed predominant asymmetric limb girdle weakness. One patient had distal weakness at onset and co-existing peripheral neuropathy. Another patient had PDB, 1 had mild cognitive deficits, and 1 had FTD. All patients had myopathic and neurogenic electromyographic findings with predominant neurogenic changes in 2. Rimmed vacuoles were infrequent, while neurogenic changes were prominent in muscle biopsies. CONCLUSIONS: VCP-opathy is a multifaceted disorder in which myopathy and peripheral neuropathy can coexist. The electrophysiological and pathological neurogenic changes raise the possibility of coexisting motor neuron involvement. Muscle Nerve, 2015 Muscle Nerve 54: 94-99, 2016 Muscle Nerve 54: 94-99, 2016.

Clinical, electrophysiologic, and imaging features of zoster-associated limb paresis.

INTRODUCTION: Paresis is a long-recognized complication of herpes zoster, but there has been comparatively little study of zoster-associated limb paresis (ZALP). METHODS: In this study we reviewed 49 Mayo Clinic patients with ZALP. RESULTS: The mean age of onset was 71 years, 67% were men, and the lower limb was affected in 55%. The mean weakness score was 2.0 (0 = normal strength, 4 = plegia). Most patients developed postherpetic neuralgia (PHN, 92% at 1 month and 65% at 3 months), and the average minimum duration of weakness was 193 days. ZALP was caused by radiculopathy (37%), plexopathy (41%), mononeuropathy (14%), and radiculoplexus neuropathy (8%). MRI demonstrated nerve enlargement, T2 signal prolongation, or enhancement in a majority (64%) of affected plexi and peripheral nerves. CONCLUSIONS: ZALP is associated with considerable weakness. It typically lasts at least several months, localizes to plexus or peripheral nerve in 63%, and is associated with high rates of PHN.

Cramp-fasciculation syndrome in patients with and without neural autoantibodies.

INTRODUCTION: We investigated the clinical, electrophysiological and neural autoantibody characteristics in cramp-fasciculation syndrome (CFS) patients. METHODS: We reviewed Mayo Clinic records from 2000 to 2011 to identify clinically defined CFS patients who underwent neural autoantibody testing. Stored sera of patients who tested positive for antibodies to voltage-gated potassium channel complex (VGKC complex) were analyzed further for leucine-rich glioma-inactivated 1 (LGI1) or contactin-associated protein-2 immunoglobulin G (CASPR2-IgG) antibodies. RESULTS: Thirty-seven patients were identified. Twelve were seropositive for neural autoantibodies. Clinical manifestations were similar in seropositive and seronegative patients, although central and autonomic neuronal hyperexcitability symptoms were more common in seropositive cases. No patients had a malignancy. Repetitive tibial nerve stimulation at 10 Hz revealed longer afterdischarges in seropositive patients. Two of 7 patients with VGKC-complex autoimmunity demonstrated LGI1 or CASPR2-IgG antibodies. Only 2 of 12 seropositive patients required immunotherapy. CONCLUSIONS: VGKC-complex autoimmunity occurs in a minority of CFS patients. Antibody positivity was associated with extramuscular manifestations, typically without malignancy. Target antigens within the VGKC complex remain unknown in most patients.

Implications of Large Language Models for Quality and Efficiency of Neurologic Care: Emerging Issues in Neurology.

Large language models (LLMs) are advanced artificial intelligence (AI) systems that excel in recognizing and generating human-like language, possibly serving as valuable tools for neurology-related information tasks. Although LLMs have shown remarkable potential in various areas, their performance in the dynamic environment of daily clinical practice remains uncertain. This article outlines multiple limitations and challenges of using LLMs in clinical settings that need to be addressed, including limited clinical reasoning, variable reliability and accuracy, reproducibility bias, self-serving bias, sponsorship bias, and potential for exacerbating health care disparities. These challenges are further compounded by practical business considerations and infrastructure requirements, including associated costs. To overcome these hurdles and harness the potential of LLMs effectively, this article includes considerations for health care organizations, researchers, and neurologists contemplating the use of LLMs in clinical practice. It is essential for health care organizations to cultivate a culture that welcomes AI solutions and aligns them seamlessly with health care operations. Clear objectives and business plans should guide the selection of AI solutions, ensuring they meet organizational needs and budget considerations. Engaging both clinical and nonclinical stakeholders can help secure necessary resources, foster trust, and ensure the long-term sustainability of AI implementations. Testing, validation, training, and ongoing monitoring are pivotal for successful integration. For neurologists, safeguarding patient data privacy is paramount. Seeking guidance from institutional information technology resources for informed, compliant decisions, and remaining vigilant against biases in LLM outputs are essential practices in responsible and unbiased utilization of AI tools. In research, obtaining institutional review board approval is crucial when dealing with patient data, even if deidentified, to ensure ethical use. Compliance with established guidelines like SPIRIT-AI, MI-CLAIM, and CONSORT-AI is necessary to maintain consistency and mitigate biases in AI research. In summary, the integration of LLMs into clinical neurology offers immense promise while presenting formidable challenges. Awareness of these considerations is vital for harnessing the potential of AI in neurologic care effectively and enhancing patient care quality and safety. The article serves as a guide for health care organizations, researchers, and neurologists navigating this transformative landscape.

Motor unit potential induced repetitive discharges (MIRDs): description of an unusual iterative discharge.

INTRODUCTION: Repetitive discharges may be recorded during nerve conduction studies (NCS) or during needle electromyography in a muscle at rest. Repetitive discharges that occur during voluntary activation and are time-locked to voluntary motor unit potentials (MUP) have not been described. METHODS: Retrospective review of motor unit potential induced repetitive discharges (MIRDs) identified in the EMG laboratory. Characteristics of each MIRD, patient demographics, other EMG findings in the same muscle, and electrophysiological diagnosis were analyzed. RESULTS: MIRDs were observed in 15 patients. The morphology and number of spikes and duration of MIRDs varied. The discharges fired at rates of 50-200 Hz. All but 2 patients had EMG findings of a chronic neurogenic disorder. CONCLUSIONS: MIRDs are rare iterative discharges time-locked to a voluntary MUP. The pathophysiology of MIRDs is unclear, but their presence may indicate a chronic neurogenic process.

Improving Neurology Clinical Care With Natural Language Processing Tools.

The integration of natural language processing (NLP) tools into neurology workflows has the potential to significantly enhance clinical care. However, it is important to address the limitations and risks associated with integrating this new technology. Recent advances in transformer-based NLP algorithms (e.g., GPT, BERT) could augment neurology clinical care by summarizing patient health information, suggesting care options, and assisting research involving large datasets. However, these NLP platforms have potential risks including fabricated facts and data security and substantial barriers for implementation. Although these risks and barriers need to be considered, the benefits for providers, patients, and communities are substantial. With these systems achieving greater functionality and the pace of medical need increasing, integrating these tools into clinical care may prove not only beneficial but necessary. Further investigation is needed to design implementation strategies, mitigate risks, and overcome barriers.

Neurologic Care of Forcibly Displaced Persons: Emerging Issues in Neurology.

There is a growing number of forcibly displaced persons (FDPs) worldwide. With more than 100 million people forcibly displaced today, there is an urgent mandate to understand the neurologic care needs of this population and how neurologists and other health care workers can most effectively provide that care. In this Emerging Issues in Neurology article, we attempt to (1) define the scope of the problem of providing neurologic care to FDPs, (2) highlight commonly encountered clinical challenges related to neurologic care of FDPs, and (3) provide useful clinical information for neurologists and other clinicians who deliver care to FDPs with neurologic needs. We address the terminology of forcible displacement and how terms may differ across a person's migration journey. Common challenges encountered by FDPs with neurologic needs across settings include loss of support systems, loss of personal health information, language barriers and differing expression of symptoms, differing belief systems, epidemiologic patterns of disease unfamiliar to the clinician, and patients' fear and perceived risks of engaging with health systems. Practical approaches are shared for clinicians who encounter an FDP with a neurologic presentation. Finally, the article discusses many unmet neurologic needs of FDPs, which require significant investment. These include addressing lapses in neurologic care during displacement and understanding the effects of forcible displacement on people with chronic neurologic conditions. Future research and educational resources should focus on improving epidemiologic intelligence for neurologic conditions across geographies, developing curricula for optimizing the neurologic care of FDPs, and evaluating the most appropriate and effective uses of health technologies in humanitarian settings.