Diagnostic modelling and therapeutic monitoring of immune-mediated necrotizing myopathy: role of electrical myotonia.

Delayed diagnosis of immunemediated necrotizing myopathy leads to increased morbidity. Patients with the chronic course without 3-hydroxy-3-methylglutaryl-coenzyme-A reductase-IgG or signal recognition particle-IgG are often challenging to diagnose. Immunotherapy response can also be difficult to assess.

Two Years of Improved Neurological Function With Nusinersen in a 48-Year-Old Patient With Spinal Muscular Atrophy Type 3.

Introduction: Nusinersen antisense oligonucleotide infusions have been shown to be effective in the treatment spinal muscular atrophy. The majority of the evidence has been collected in young type 1 and type 2 patients, and evidence of efficacy in adult patients is limited.

Case Report: A 48-year-old woman with spinal muscular atrophy type 3 who has received the loading dose and 8 maintenance infusions over an 8-month period.

A systematic review of Gamma-aminobutyric Acid Receptor Type B autoimmunity.

Objective: To review the available research to describe the clinical characteristics and neoplastic associations of patients with gamma-aminobutyric acid receptor type B (GABAB-R) autoantibodies.

Methods: Literature was reviewed on PubMed, Mendeley literature search, and the American Academy of Neurology database for articles published from June 2008 to October of 2018 using a variety of key words. These key words include: "gamma-aminobutyric acid seizures," "gamma-aminobutyric acid limbic encephalitis", "GABA(B) receptor antibodies," "autoimmune encephalitis," "autoimmune epilepsy," "GABA(B) encephalitis, " and "GABA paraneoplastic.

Needle electromyography and histopathologic correlation in myopathies.

Introduction: Needle electromyography (EMG) findings help confirm myopathy and may indicate specific pathologic changes on muscle biopsy.

Methods: We conducted a retrospective chart review of 218 consecutive patients referred for muscle biopsy. Presence of specific needle EMG findings was correlated with pathologic findings of inflammation, necrosis, splitting, and vacuolar changes.

Needle EMG of Thenar Muscles in Less Severe Carpal Tunnel Syndrome.

Introduction: The value of needle electromyography (EMG) in thenar muscles in patients with less severe carpal tunnel syndrome is controversial.

Methods: Patients referred for electrodiagnostic testing for carpal tunnel syndrome, in which nerve conduction study demonstrated median sensory nerve conduction study abnormalities and either normal median motor nerve conduction study or only prolonged median motor distal latencies (DLs) (with normal amplitudes) were prospectively studied. Patients with low-median compound muscle action potential amplitudes or any other EMG abnormality were excluded.

Rheumatology and Neurology.

Purpose Of Review: This article reviews the various rheumatologic disorders that have neurologic complications and manifestations.

Recent Findings: Recent advances have improved the understanding of the true epidemiology of many rheumatologic diseases and their complications. Many years of observation have clarified findings even in rarer disorders.

Whole exome sequencing of a patient with suspected mitochondrial myopathy reveals novel compound heterozygous variants in .

Background: Pathogenic variants in ryanodine receptor 1 ( MIM# 180901) are the cause of congenital myopathy with fiber-type disproportion, malignant hyperthermia susceptibility type 1, central core disease of muscle, multiminicore disease and other congenital myopathies.

Methods: We present a patient with global developmental delay, hypotonia, myopathy, joint hypermobility, and multiple other systemic complaints that were noted early in life. Later she was found to have multiple bone deformities involving her spine, with severe scoliosis that was corrected surgically.

Eosinophilic fasciitis with subjacent myositis.

Introduction: Eosinophilic fasciitis (EF) is a rare disorder that can present with muscle symptoms that mimic other neuromuscular diseases.

Methods: We report the case of a 43-year-old woman with chronic muscle aches, tightness, and stiffness with hypertrophied, well-defined muscles despite physical inactivity, and thickened skin with reduced elasticity and discoloration.

Results: Except for mild peripheral eosinophilia, laboratory studies, including blood count, electrolytes, paraneoplastic panel, muscle enzymes, thyroid function, and serum protein electrophoresis, were normal.

Whole Exome Sequencing Leading to the Diagnosis of Dysferlinopathy with a Novel Missense Mutation (c.959G>C).

Dysferlinopathy is an uncommon, progressive muscular dystrophy that has a wide phenotypic variability and primarily supportive management (Nguyen et al., 2007; Narayanaswami et al., 2014).

Early Absent Pupillary Light Reflexes After Cardiac Arrest in Patients Treated with Therapeutic Hypothermia.

Loss of pupillary light reactivity is one recognized indicator of poor prognosis after cardiopulmonary resuscitation (CPR). However, drug overdose, low cardiac output, and/or resuscitation drugs can lead to impaired pupillary light reflex. To investigate pupillary light reflex status before therapeutic hypothermia (TH) in relation to neurological outcome, we retrospectively reviewed the data of a prospectively implemented TH protocol in patients with cardiac arrest (CA) at Mayo Clinic in Jacksonville, Florida (January 2006-January 2012), and Mayo Clinic in Scottsdale, Arizona (August 2010-March 2014).

Milestone-compatible neurology resident assessments: A role for observable practice activities.

Objective: Beginning in 2014, US neurology residency programs were required to report each trainee's educational progression within 29 neurology Milestone competency domains. Trainee assessment systems will need to be adapted to inform these requirements. The primary aims of this study were to validate neurology resident assessment content using observable practice activities (OPAs) and to develop assessment formats easily translated to the Neurology Milestones.

Improving referring physicians' understanding of electromyography reports when qualifying radiculopathies: a need for standardized terminology.

Electromyographic (EMG) reporting of radiculopathies is not standardized, and the terminology used in reports can be misinterpreted by referring physicians. Physicians who refer patients for EMG studies at the Mayo Clinic were surveyed about their understanding of 6 different EMG interpretations of an S1 radiculopathy. Of 45 responders, the terms “acute, active,” “chronic, inactive,” and “old” were interpreted consistently by 95%, 98%, and 84% of responders, respectively.

Popliteus muscle hemorrhage as a rare cause of a proximal tibial neuropathy.

Proximal tibial neuropathy is an uncommon focal mononeuropathy that is most often caused by trauma, ischemia, or neoplastic infiltration or compression of the tibial nerve. We report a patient who presented with a tibial neuropathy following a leg injury, which initially mimicked a lumbosacral radiculopathy but which was the result of a proximal tibial neuropathy. Electrophysiologic studies confirmed a proximal tibial neuropathy and MRI revealed a popliteus muscle hemorrhage with mass effect on the tibial nerve.

Colchicine-induced myoneuropathy mimicking polyradiculoneuropathy.

We report a patient with colchicine-induced myoneuropathy. Myoneuropathy is an under-recognized complication of colchicine. The weakness seen in our patient improved fairly rapidly after discontinuation of colchicine.

Utility of minimum F-wave latencies compared with F-estimates and absolute reference values in S1 radiculopathies: are they still needed?

Introduction: The utility of F-waves in assessing radiculopathies is debated. The aim of this study is to determine the frequency of abnormal minimum tibial F-wave latencies compared to an F-estimate and an absolute reference value in patients with electromyography (EMG) confirmed S1 radiculopathies.

Methods: A retrospective review of F-waves in patients with an EMG-confirmed isolated S1 radiculopathy was performed.

Electrodiagnostic evaluation of ulnar neuropathy and other upper extremity mononeuropathies.

Upper extremity mononeuropathies are some of the common disorders seen in neurophysiology laboratories. Electrophysiologic studies rely on accurate localization based on knowledge of applicable anatomy and features of history and physical examination. Careful electrodiagnostic studies provide an accurate diagnosis, help localize the lesion site, exclude alternate diagnoses, reveal unsuspected diagnoses, determine pathophysiology of lesions, and assess severity, timeframe, and prognosis of lesions.

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)-like phenotype: an expanded clinical spectrum of POLG1 mutations.

The aim of the study was to determine the prevalence of MNGIE-like phenotype in patients with recessive POLG1 mutations. Mutations in the POLG1 gene, which encodes for the catalytic subunit of the mitochondrial DNA polymerase gamma essential for mitochondrial DNA replication, cause a wide spectrum of mitochondrial disorders. Common phenotypes associated with POLG1 mutations include Alpers syndrome, ataxia-neuropathy syndrome, and progressive external ophthalmoplegia (PEO).

The effect of paired stimuli on blink reflex latencies in normal subjects.

Introduction: In this study we assessed the effect of paired stimuli on the latencies and amplitudes of the blink reflex.

Methods: Blink reflexes were performed with single and paired (5-ms interstimulus interval) stimuli in 47 patients. The changes in latencies between paired and single stimuli were calculated.

The office evaluation of weakness.

The office evaluation of weakness can be a daunting task. Many different disorders affecting many different parts of the nervous system can manifest with "weakness," and several nonneurologic conditions may present with complaints of weakness. It is the job of the neurologist to determine whether a patient has neurologic weakness or suffers simply from fatigue.

Dystrophinopathy presenting with arrhythmia in an asymptomatic 34-year-old man: a case report.

Introduction: Important clues in the recognition of individuals with dystrophin gene mutations are illuminated in this case report. In particular, this report seeks to broaden the perspective of early signs and symptoms of a potentially life-limiting genetic disorder. This group of disorders is generally considered to be a pediatric muscular dystrophy when in actual fact, this case report may represent a spectrum of subclinically affected adults.