Mild motor impairment as prodromal state in amyotrophic lateral sclerosis:A new diagnostic entity

Amyotrophic lateral sclerosis, when viewed as a biological entity rather than a clinical syndrome, probably evolves along a continuum, with the initial clinically silent phase eventually evolving into clinically manifest amyotrophic lateral sclerosis. Since motor neuron degeneration is incremental and cumulative over time, it stands to reason that the clinical syndrome of amyotrophic lateral sclerosis is probably preceded by a prodromal state characterized by minor motor abnormalities that are initially insufficient to permit a diagnosis of amyotrophic lateral sclerosis. This prodromal period, however, is usually missed, given the invariably long delays between symptom onset and diagnostic evaluation. The Pre-Symptomatic Familial ALS Study, a cohort study of pre-symptomatic gene mutation carriers, offers a unique opportunity to observe what is typically unseen. Here we describe the clinical characterization of 20 pre-symptomatic mutation carriers (in SOD1, FUS and C9orf72) whose phenoconversion to clinically manifest disease has been prospectively studied. In so doing, we observed a prodromal phase of mild motor impairment in 11 of 20 phenoconverters. Among the n = 12 SOD1 A4V mutation carriers, phenoconversion was characterized by abrupt onset of weakness, with a short (1–3.5 months) prodromal period observable in a small minority (n = 3); the observable prodrome invariably involved the lower motor neuron axis. By contrast, in all n = 3 SOD1 I113T mutation carriers, diffuse lower motor neuron and upper motor neuron signs evolved insidiously during a prodromal period that extended over a period of many years; prodromal manifestations eventually coalesced into a clinical syndrome that is recognizable as amyotrophic lateral sclerosis. Similarly, in all n = 3 C9orf72 hexanucleotide repeat expansion mutation carriers, focal or multifocal manifestations of disease evolved gradually over a prodromal period of 1–2 years. Clinically manifest ALS also emerged following a prodromal period of mild motor impairment, lasting >4 years and ∼9 months, respectively, in n = 2 with other gene mutations (SOD1 L106V and FUS c.521del6). On the basis of this empirical evidence, we conclude that mild motor impairment is an observable state that precedes clinically manifest disease in three of the most common genetic forms of amyotrophic lateral sclerosis (SOD1, FUS, C9orf72), and perhaps in all genetic amyotrophic lateral sclerosis; we also propose that this might be true of non-genetic amyotrophic lateral sclerosis. As a diagnostic label, mild motor impairment provides the language to describe the indeterminate (and sometimes intermediate) transition between the unaffected state and clinically manifest amyotrophic lateral sclerosis. Recognizing mild motor impairment as a distinct clinical entity should generate fresh urgency for developing biomarkers reflecting the earliest events in the degenerative cascade, with potential to reduce the diagnostic delay and to permit earlier therapeutic intervention

The Inverse Lhermitte Phenomenon Suggests Nitrous Oxide-Induced Myelopathy: Case Report and Review of the Literature

Nitrous oxide-induced myelopathy is a relatively well-known clinical entity. Less well-known, however, is the rare inverse Lhermitte phenomenon, where neck flexion elicits an ascending, rather than descending, electric shock-like sensation. This is a characteristic symptom and sign that may occur in nitrous oxide toxicity. In this article, we present the case of a patient who was admitted to our hospital with suspected Guillain-Barré syndrome due to her ascending numbness and unsteady gait. We describe her examination and laboratory features leading to the correct diagnosis, along with a historical review of the various subtypes of the Lhermitte phenomenon and the pathophysiology of nitrous oxide-induced myelopathy

Addressing Outcome Measure Variability in Myasthenia Gravis Clinical Trials

An increasing number of clinical trials are enrolling patients with myasthenia gravis (MG). A lack of standardization in the performance of outcome measures leads to confusion among site research teams and is a source of variability in clinical trial data. MGNet, the NIH-supported Rare Disease Clinical Research Network for MG, views standardization of MG outcome measures as a critical need. To address this issue, a group of experts summarized key outcome measures used in MG clinical trials and a symposium was convened to address issues contributing to outcome measure variability. Consensus recommendations resulted in changes to outcome measure instructions and, in some cases, modifications to specific instruments. Recommended changes were posted for public commentary before finalization. Changes to the MG-Activities of Daily Living, MG-Quality of Life-15r, and MG-Impairment Index were limited to adding details to the administration instructions. Recommendations for proper positioning of participants and how to score items that could not be performed because of non-MG reasons were provided for the MG Composite. The Quantitative MG (QMG) score required the most attention, and changes were made both to the instructions and the performance of certain items resulting in the QMG-Revised. The Postintervention Status was believed to have a limited role in clinical trials, except for the concept of minimal manifestation status. As a next step, training materials and revised source documents, which will be freely available to study teams, will be created and posted on the MGNet website. Further studies are needed to validate changes made to the QMG-Revised

Addressing Outcome Measure Variability in Myasthenia Gravis Clinical Trials.

An increasing number of clinical trials are enrolling patients with myasthenia gravis (MG). A lack of standardization in the performance of outcome measures leads to confusion among site research teams and is a source of variability in clinical trial data. MGNet, the NIH-supported Rare Disease Clinical Research Network for MG, views standardization of MG outcome measures as a critical need. To address this issue, a group of experts summarized key outcome measures used in MG clinical trials and a symposium was convened to address issues contributing to outcome measure variability. Consensus recommendations resulted in changes to outcome measure instructions and, in some cases, modifications to specific instruments. Recommended changes were posted for public commentary before finalization. Changes to the MG-Activities of Daily Living, MG-Quality of Life-15r, and MG-Impairment Index were limited to adding details to the administration instructions. Recommendations for proper positioning of participants and how to score items that could not be performed because of non-MG reasons were provided for the MG Composite. The Quantitative MG (QMG) score required the most attention, and changes were made both to the instructions and the performance of certain items resulting in the QMG-Revised. The Postintervention Status was believed to have a limited role in clinical trials, except for the concept of minimal manifestation status. As a next step, training materials and revised source documents, which will be freely available to study teams, will be created and posted on the MGNet website. Further studies are needed to validate changes made to the QMG-Revised

Harnessing the power of the electronic health record for ALS research and quality improvement: CReATe CAPTURE‐ALS and the ALS Toolkit

The electronic health record (EHR) is designed principally to support the provision and documentation of clinical care, as well as billing and insurance claims. Broad implementation of the EHR, however, also yields an opportunity to use EHR data for other purposes, including research and quality improvement. Indeed, effective use of clinical data for research purposes has been a longstanding goal of physicians who provide care for patients with ALS, but the quality and completeness of clinical data, as well as the burden of double data entry into the EHR and into a research database, have been persistent barriers. These factors provided motivation for the development of the ALS Toolkit, a set of interactive digital forms within the EHR that enable easy, consistent, and structured capture of information relevant to ALS patient care (as well as research and quality improvement) during clinical encounters. Routine use of the ALS Toolkit within the context of the CReATe Consortium’s IRB-approved Clinical Procedures to Support Research in ALS (CAPTURE-ALS) study protocol, permits aggregation of structured ALS patient data, with the goals of empowering research and driving quality improvement. Widespread use of the ALS Toolkit through the CAPTURE-ALS protocol will help to ensure that ALS clinics become a driving force for collecting and aggregating clinical data in a way that reflects the true diversity of the populations affected by this disease, rather than the restricted subset of patients that currently participate in dedicated research studies

Addressing Outcome Measure Variability in Myasthenia Gravis Clinical Trials

An increasing number of clinical trials are enrolling patients with myasthenia gravis (MG). A lack of standardization in the performance of outcome measures leads to confusion among site research teams and is a source of variability in clinical trial data. MGNet, the NIH-supported Rare Disease Clinical Research Network for MG, views standardization of MG outcome measures as a critical need. To address this issue, a group of experts summarized key outcome measures used in MG clinical trials and a symposium was convened to address issues contributing to outcome measure variability. Consensus recommendations resulted in changes to outcome measure instructions and, in some cases, modifications to specific instruments. Recommended changes were posted for public commentary before finalization. Changes to the MG-Activities of Daily Living, MG-Quality of Life-15r, and MG-Impairment Index were limited to adding details to the administration instructions. Recommendations for proper positioning of participants and how to score items that could not be performed because of non-MG reasons were provided for the MG Composite. The Quantitative MG (QMG) score required the most attention, and changes were made both to the instructions and the performance of certain items resulting in the QMG-Revised. The Postintervention Status was believed to have a limited role in clinical trials, except for the concept of minimal manifestation status. As a next step, training materials and revised source documents, which will be freely available to study teams, will be created and posted on the MGNet website. Further studies are needed to validate changes made to the QMG-Revised

Addressing Outcome Measure Variability in Myasthenia Gravis Clinical Trials

An increasing number of clinical trials are enrolling patients with myasthenia gravis (MG). A lack of standardization in the performance of outcome measures leads to confusion amongst site research teams and is a source of variability in clinical trial data. MGNet, the NIH-supported Rare Disease Clinical Research Network for MG, views standardization of MG outcome measures as a critical need. To address this issue, a group of experts summarized key outcome measures used in MG clinical trials and a symposium was convened to address issues contributing to outcome measure variability. Consensus recommendations resulted in changes to outcome measure instructions, and in some cases, modifications to specific instruments. Recommended changes were posted for public commentary prior to finalization. Changes to the MG-Activities of Daily Living, MG-Quality of Life-15r, and MG-Impairment Index were limited to adding details to the administration instructions. Recommendations for proper positioning of subjects and how to score items that could not be performed due to non-MG reasons were provided for the MG Composite. The Quantitative MG (QMG) Score required the most attention, and changes were made both to the instructions and the performance of certain items resulting in the QMG-Revised (QMG-R). The Post-Intervention Status was felt to have a limited role in clinical trials, except for the concept of minimal manifestation status. As a next step training materials and revised source documents, which will be freely available to study teams, will be created and posted on the MGNet website. Further studies are needed to validate changes made to the QMG-R