Effects of mexiletine on hyperexcitability in sporadic amyotrophic lateral sclerosis: Preliminary findings from a small phase II randomized controlled trial.

BACKGROUND: To collect preliminary data on the effects of mexiletine on cortical and axonal hyperexcitability in sporadic amyotrophic lateral sclerosis (ALS) in a phase 2 double-blind randomized controlled trial. METHODS: Twenty ALS subjects were randomized to placebo and mexiletine 300 or 600 mg daily for 4 wk and assessed by transcranial magnetic stimulation and axonal excitability studies. The primary endpoint was change in resting motor threshold (RMT). RESULTS: RMT was unchanged with 4 wk of mexiletine (combined active therapies) as compared to placebo, which showed a significant increase (P = .039). Reductions of motor evoked potential (MEP) amplitude (P = .013) and accommodation half-time (P = .002), secondary outcome measures of cortical and axonal excitability, respectively, were also evident at 4 wk on mexiletine. CONCLUSIONS: The relative stabilization of RMT in the treated subjects was unexpected and could be attributed to unaccounted sources of error or chance. However, a possible alternative cause is neuromodulation preventing an increase. The change in MEP amplitude and accommodation half-time supports the reduction of cortical and axonal hyperexcitability with mexiletine.

Thymectomy may not be associated with clinical improvement in MuSK myasthenia gravis.

INTRODUCTION: A randomized trial demonstrated benefit from thymectomy in nonthymomatous acetylcholine receptor (AChR)-antibody positive myasthenia gravis (MG). Uncontrolled observational and histologic studies suggest thymectomy may not be efficacious in anti-muscle-specific kinase (MuSK)-MG. METHODS: The therapeutic impact of thymectomy was evaluated from data collected for a multicenter, retrospective blinded review of rituximab in MuSK-MG. RESULTS: Baseline characteristics were similar between thymectomy (n = 26) and nonthymectomy (n = 29) groups, including treatment with rituximab (42% vs. 45%). At last visit, 35% of thymectomy subjects reached the primary endpoint, a Myasthenia Gravis Foundation of America (MGFA) post-intervention status (PIS) score of minimal manifestations (MM) or better, compared with 55% of controls (P = 0.17). After controlling for age at onset of MG, rituximab, prednisone, and intravenous immunoglobulin/plasma exchange treatment, thymectomy was not associated with greater likelihood of favorable clinical outcome (odds ratio = 0.43, 95% confidence interval 0.12-1.53, P = 0.19). DISCUSSION: Thymectomy was not associated with additional clinical improvement in this multicenter cohort of MuSK-MG patients. Muscle Nerve 59:404-410, 2019.

Aspiration Screening in Motor Neuron Disease: Preliminary Results From Utilization of the Yale Swallow Protocol.

Purpose Dysphagia is a common symptom experienced by patients with motor neuron disease (MND). The Yale Swallow Protocol (YSP) is a validated screening instrument for identifying patients at risk for aspiration. The purpose of this exploratory cross-sectional, multicenter study was to investigate how the YSP results in identifying aspiration risk in patients with MND in comparison with aspiration observed during a videofluoroscopic swallow study (VFSS). Method Participants referred for VFSS as part of clinical management were recruited from four specialized MND clinics. All participants were administered the YSP immediately prior to the VFSS by a speech-language pathologist, with results recorded as pass or fail. Aspiration on VFSS was determined using the Penetration-Aspiration Scale (scores 6-8). A 2 × 2 contingency table was constructed to compare results of YSP with those on VFSS. Results Thirty-one patients with MND (13 males, 18 females; M age = 64 ± 12 years) referred for VFSS participated in this study. Of the 22 patients who failed the YSP, interrupted drinking was the most frequent reason (65%). Compared to the VFSS, the YSP yielded a sensitivity of 80%, a specificity of 33%, positive predictive value of 36%, and negative predictive value of 78%. Conclusions The YSP is a simple tool and easy to utilize and has a high sensitivity in identifying aspiration risk in amyotrophic lateral sclerosis. A future investigation with a larger sample size is needed to better investigate the utility of YSP as a screening tool for this population.

A Shortage of Neurologists We Must Act Now: A Report From the AAN 2019 Transforming Leaders Program.

In nearly every US state today, a large mismatch exists between the need for neurologists and neurological services and the availability of neurologists to provide these services. Patients with neurologic disorders are rising in prevalence and require access to high level care to reduce disability. The current neurology mismatch reduces access to care, worsens patient outcomes, and erodes career satisfaction and quality of life for neurologists as they face increasingly insurmountable demands. As a community, we must address this mismatch in the demand and supply of neurological care in an aggressive and sustained manner to ensure the future health of our patients and our specialty. The American Academy of Neurology has multiple ongoing initiatives to help reduce and resolve the existing mismatch. With the intent of raising awareness and widening the debate nationally, we present a strategic plan that the Academy could implement to coordinate and expand existing efforts. We characterize the suggested strategies as: shaping the demand, enhancing the workforce, and advocating for neurologist value The proposed framework is based on available data and expert opinion when data were lacking. Prioritization of strategies will vary by geography, practice setting, and local resources. We believe the time to act is now, to allow concerted effort and targeted interventions to avert this looming public health crisis.

Rituximab as treatment for anti-MuSK myasthenia gravis: Multicenter blinded prospective review.

OBJECTIVE: To evaluate the efficacy of rituximab in treatment of anti-muscle-specific kinase (MuSK) myasthenia gravis (MG). METHODS: This was a multicenter, blinded, prospective review, comparing anti-MuSK-positive patients with MG treated with rituximab to those not treated with rituximab. The primary clinical endpoint was the Myasthenia Gravis Status and Treatment Intensity (MGSTI), a novel outcome that combines the Myasthenia Gravis Foundation of America (MGFA) postintervention status (PIS) and the number and dosages of other immunosuppressant therapies used. A priori, an MGSTI of level ≤2 was used to define a favorable outcome. Secondary outcomes included modified MGFA PIS of minimal manifestations or better, mean/median prednisone dose, and mean/median doses of other immunosuppressant drugs. RESULTS: Seventy-seven of 119 patients with anti-MuSK MG evaluated between January 1, 2005, and January 1, 2015, at 10 neuromuscular centers were selected for analysis after review of limited clinical data by a blinded expert panel. An additional 22 patients were excluded due to insufficient follow-up. Baseline characteristics were similar between the rituximab-treated patients (n = 24) and the controls (n = 31). Median follow-up duration was >3.5 years. At last visit, 58% (14/24) of rituximab-treated patients reached the primary outcome compared to 16% (5/31) of controls (p = 0.002). Number needed to treat for the primary outcome is 2.4. At last visit, 29% of rituximab-treated patients were taking prednisone (mean dose 4.5 mg/day) compared to 74% of controls (mean dose 13 mg/day) (p = 0.001 and p = 0.005). CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with anti-MuSK MG, rituximab increased the probability of a favorable outcome.

Reversible posterior leukoencephalopathy in connective tissue diseases.

OBJECTIVES: To describe a case of reversible posterior leukoencephalopathy (RPLS) involving a patient with systemic lupus erythematosus (SLE) and to review the medical literature to define the epidemiological, clinical, radiological, and therapeutic aspects of this syndrome in various connective tissue diseases. METHODS: Report of 1 case and review of the English literature using Medline search from 1967 to 2005. RESULTS: Including our reported case, RPLS has been identified in 13 patients with connective tissue disease. In separate case reports, 9 SLE patients, 2 Wegener's granulomatosis (WG) patients, and 1 patient with SLE and systemic sclerosis presented with RPLS. Associated risk factors included malignant hypertension, acute renal failure, and recent treatment with cyclophosphamide, cyclosporine, or methylprednisolone. Patients were treated with blood pressure control, hemodialysis, or withdrawal of the offending drug. In our patient, plasmapheresis and high-dose methylprednisolone resulted in a full recovery. In most cases, complete resolution of neurological symptoms occur within 2 weeks of presentation, along with improvement or resolution of imaging abnormalities. CONCLUSION: RPLS is a clinicoradiological entity, associated with reversible white matter edema involving most commonly the posterior central nervous system circulation. Seizures and altered mental status in patients with SLE or WG can pose difficult diagnostic and therapeutic challenges. The differential diagnosis is broad and includes infection, uremia, hypertension, infarction, thrombosis, demyelinating disorders, and vasculitis. Accurate diagnosis of RPLS and its differentiation from other, more common causes of the central nervous system is essential to ensure the best possible outcome in this rare but life-threatening neurological disorder.

Amyotrophic lateral sclerosis and neurosarcoidosis: a case report.

Amyotrophic lateral sclerosis (ALS) remains a clinical diagnosis without definable biomarkers. The pathomechanism of motor neuron degeneration in ALS has yet to be elucidated. Here we present a case of limb-onset ALS, with autopsy findings of Bunina bodies and skein-like inclusions, as well as sarcoid granulomas predominating among motor neurons. The targeting of the motor neurons by the sarcoid inflammation raises questions regarding the role of cellular immunity in the pathomechanisms for ALS.