Muscle Biopsy and Electromyography Correlation

Introduction: In myopathies, the correlation of individual electromyographic and histopathologic findings remains poorly explored, as most previous studies have focused on the ability of muscle biopsy and electromyography to distinguish the neuropathic vs. myopathic nature of the underlying neuromuscular disease.Methods: We identified 100 patients who had a muscle biopsy and electromyography performed on identical muscles. We used a detailed grading system ranging from 0- normal to 4- severe; and graded 16 histopathologic findings in each biopsy. Electromyography findings were also graded from 0 to 4 according to the standard protocol in our EMG laboratory. We used Kendall's tau for non-parametric ordinal correlation analysis.Results: Fibrillation potentials correlated with atrophic, necrotic, and regenerating fibers, fibers harboring vacuoles, fiber splitting, fibers reacting for non-specific esterase, fibers with congophilic inclusions, inflammation (endoymysial and perimysial), and increased endomysial connective tissue. Short-duration motor unit potentials correlated with atrophic, necrotic, and regenerating fibers, increased endomysial connective tissue, and perimysial inflammation. Long-duration motor unit potentials correlated with fiber-type grouping. Increased phases of motor unit potentials correlated with atrophic fibers, increased endomysial connective tissue, and fibers reacting for non-specific esterase; while increased turns correlated with atrophic and regenerating fibers, increased endomysial connective tissue and target formations. Rapid recruitment correlated with regenerating fibers, perimysial inflammation, and increased endomysial connective tissue.Discussion: By demonstrating a clear correlation of various electromyographic and histopathologic findings, this study improves interpreting electrodiagnostic testing in myopathies, and serves as the basis to further assess the correlation between clinical, electromyographic, and histopathologic findings

Current status of clinical outcome measures in inclusion body myositis: a systematised review

OBJECTIVES: Sporadic inclusion body myositis (IBM) is a debilitating idiopathic inflammatory myopathy (IIM) which affects hand function, ambulation, and swallowing. There is no approved pharmacological therapy for IBM, and there is a lack of suitable outcome measure to assess the effect of an intervention. The IBM scientific interest group under IMACS reviewed the previously used outcome measures in IBM clinical studies to lay the path for developing a core set of outcome measures in IBM. METHODS: In this systematised review, we have extracted all outcome measures reported in IBM clinical studies to determine what measures were being used and to assess the need for optimising outcome measures in IBM. RESULTS: We found 13 observational studies, 17 open-label clinical trials, and 15 randomised control trials (RCTs) in IBM. Six-minute walk distance, IBM-functional rating scale (IBM-FRS), quantitative muscle testing, manual muscle testing, maximal voluntary isometric contraction testing, and thigh muscle volume measured by MRI were used as primary outcome measures. Twelve different outcome measures of motor function were used in IBM clinical trials. IBM-FRS was the most used measure of functionality. Swallowing function was reported as a secondary outcome measure in only 3 RCTs. CONCLUSIONS: There are inconsistencies in using outcome measures in clinical studies in IBM. The core set measures developed by the IMACS group for other IIMs are not directly applicable to IBM. As a result, there is an unmet need for an IBM-specific core set of measures to facilitate the evaluation of new potential therapeutics for IBM

Supplemental table e2_treatment details

Treatment detail

Supplemental table e1_ laboratory results

Laboratory result

Data from: Sporadic late-onset nemaline myopathy: clinical spectrum, survival and treatment outcomes

OBJECTIVES: To describe the clinical phenotype, long-term treatment outcome and overall survival of sporadic late onset nemaline myopathy (SLONM) with or without a monoclonal protein (MP). METHODS: we conducted a retrospective chart review of patients seen between September 2000 and June 2017 and collected clinical, laboratory and survival data. Treatment response was classified as mild, moderate, or marked as adjudged by predefined criteria. RESULTS: We identified 28 patients with SLONM, 17 (61%) had an associated MP. Median age at symptom onset was 62 years. Diagnosis was often delayed by a median of 35 months from symptom onset. There was no difference in clinical or laboratory features between patients with or without MP. Although the majority of patients had proximal or axial weakness at onset, about 18% of patients had atypical presentations. 7/9 (78%) patients receiving intravenous immunoglobulin (IVIG), 6/8 (75%) receiving hematologic therapy as either autologous stem cell transplant (ASCT), or chemotherapy and 1/8 (13%) receiving immunosuppressive therapies responded to treatment (p=0.001). All 3 patients with marked response were treated with IVIG, 2 of them had a MP. The 5-year and 10-year overall survivals from symptom onset were 92% and 68% respectively, with no difference between patients with or without MP. CONCLUSIONS: SLONM has a wide spectrum of clinical presentations. In this contemporary case series, overall survival of patients did not seem to be affected by the presence of a MP. Initial treatment with IVIG is reasonable in all patients, followed by ASCT or chemotherapy as second-line therapy in patients with an associated MP

Chronic inflammatory demyelinating polyradiculoneuropathy—Diagnostic pitfalls and treatment approach

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is characterized by progressive weakness and sensory loss, often affecting patientsʼ ability to walk and perform activities of daily living independently. With the lack of a diagnostic biomarker, the diagnosis relies on clinical suspicion, clinical findings, and the demonstration of demyelinating changes on electrodiagnostic (EDx) testing and nerve pathology. As a result, patients can often be misdiagnosed with CIDP and unnecessarily treated with immunotherapy. Interpreting the EDx testing and cerebrospinal fluid findings in light of the clinical phenotype, recognizing atypical forms of CIDP, and screening for CIDP mimickers are the mainstays of the approach to patients suspected of having CIDP, and are detailed in this review. We also review the currently available treatment options, including intravenous immunoglobulin (IVIg), corticosteroids (CCS), and plasma exchange (PE), and discuss how to approach treatment‐refractory cases. Finally, we emphasize the need to adopt objective outcome measures to monitor treatment response.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/166169/1/mus27046.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/166169/2/mus27046_am.pd