Defining SOD1 ALS natural history to guide therapeutic clinical trial design.

IMPORTANCE: Understanding the natural history of familial amyotrophic lateral sclerosis (ALS) caused by SOD1 mutations (ALSSOD1) will provide key information for optimising clinical trials in this patient population. OBJECTIVE: To establish an updated natural history of ALSSOD1. DESIGN, SETTING AND PARTICIPANTS: Retrospective cohort study from 15 medical centres in North America evaluated records from 175 patients with ALS with genetically confirmed SOD1 mutations, cared for after the year 2000. MAIN OUTCOMES AND MEASURES: Age of onset, survival, ALS Functional Rating Scale (ALS-FRS) scores and respiratory function were analysed. Patients with the A4V (Ala-Val) SOD1 mutation (SOD1A4V), the largest mutation population in North America with an aggressive disease progression, were distinguished from other SOD1 mutation patients (SOD1non-A4V) for analysis. RESULTS: Mean age of disease onset was 49.7±12.3 years (mean±SD) for all SOD1 patients, with no statistical significance between SOD1A4V and SOD1non-A4V (p=0.72, Kruskal-Wallis). Total SOD1 patient median survival was 2.7 years. Mean disease duration for all SOD1 was 4.6±6.0 and 1.4±0.7 years for SOD1A4V. SOD1A4V survival probability (median survival 1.2 years) was significantly decreased compared with SOD1non-A4V (median survival 6.8 years; p<0.0001, log-rank). A statistically significant increase in ALS-FRS decline in SOD1A4V compared with SOD1non-A4V participants (p=0.02) was observed, as well as a statistically significant increase in ALS-forced vital capacity decline in SOD1A4V compared with SOD1non-A4V (p=0.02). CONCLUSIONS AND RELEVANCE: SOD1A4V is an aggressive, but relatively homogeneous form of ALS. These SOD1-specific ALS natural history data will be important for the design and implementation of clinical trials in the ALSSOD1 patient population.

Satisfactory Response With Achieving Maintenance Low-Dose Prednisone in Generalized Myasthenia Gravis.

OBJECTIVES: To estimate the satisfactory response rate (SR%) with achieving maintenance, low-dose prednisone in acetylcholine receptor antibody-positive generalized myasthenia gravis. METHODS: In this retrospective study, we estimate the SR% as defined by (remission/minimal manifestations status for at least 6 months using 7.5 mg or less of prednisone daily, for maintenance treatment at 2, 4, and 6 years after symptoms onset) for patients who were not taking steroid-sparing immunosuppressant (SSI) as a primary outcome and for patients taking an SSI as a secondary outcome. RESULTS: Forty-five patients were not taking an SSI at 2 years, 34 patients at 4 years, and 17 patients at 6 years; SR% was 44.4%, 64.7%, and 58.8%, respectively. Thirty-six patients were taking an SSI at 2 years, 22 patients at 4 years, and 15 patients at 6 years; the SR% was 50.0%, 45.4%, and 66.7%, respectively. CONCLUSIONS: Nearly half of the generalized myasthenia gravis patients who were not taking an SSI achieved an SR.

Less is More in Diabetic Neuropathy Diagnosis: Comparison of Quantitative Sudomotor Axon Reflex and Skin Biopsy.

OBJECTIVES: To compare the frequency of abnormalities in epidermal nerve fiber density (ENFD) and quantitative sudomotor axon reflex (QSART) in patients with diabetic distal symmetric polyneuropathy (DSPN). METHODS: Nerve conduction studies, ENFD, and QSART data were obtained pre- and postexercise, in patients enrolled in a prospective diabetic neuropathy study. McNemar's test was applied to compare the yield of ENFD and QSART. RESULTS: Eighteen patients (58 ± 4 years) were enrolled, with 36 data collection points. In diabetic DSPN and diabetic large fiber DSPN (DSPN-L), abnormal ENFD (77% and 100% respectively) is more frequent than abnormal QSART (39% and 35%, respectively) (P value = 0.001 in diabetic DSPN and P value = 0.0002 in diabetic DSPN-L), whereas in diabetic small fiber DSPN (DSPN-S), both tests have similar yields (47%). CONCLUSIONS: ENFD has a high diagnostic yield in diabetic DSPN and DSPN-L. Including QSART data adds little to the sensitivity of EFND in DSPN-S.

Primary Lateral Sclerosis and Early Upper Motor Neuron Disease: Characteristics of a Cross-Sectional Population.

OBJECTIVES: The goals of this study were to characterize clinical and electrophysiologic findings of subjects with upper motor neuron disease and to explore feasibility of clinical trials in this population. METHODS: Twenty northeast amyotrophic lateral sclerosis consortium (northeast amyotrophic lateral sclerosis) sites performed chart reviews to identify active clinical pure upper motor neuron disease patients. Patients with hereditary spastic paraplegia or meeting revised El Escorial electrodiagnostic criteria for amyotrophic lateral sclerosis were excluded. Patients were classified into 2 groups according to the presence or absence of minor electromyography (EMG) abnormalities. RESULTS: Two hundred thirty-three subjects with upper motor neuron disease were identified; 217 had available EMG data. Normal EMGs were seen in 140 subjects, and 77 had minor denervation. Mean disease duration was 84 (±80) months for the entire cohort with no difference seen between the 2 groups. No difference was seen in clinical symptoms, disability, or outcome measures between the 2 groups after correcting for multiple comparisons. CONCLUSIONS: Minor EMG abnormalities were not associated with phenotypic differences in a clinical upper motor neuron disease population. These findings suggest that subtle EMG abnormalities can not necessarily be used as a prognostic tool in patients with clinical upper motor neuron disease. This study also demonstrates the availability of a large number of patients with upper motor neuron diseases within the northeast amyotrophic lateral sclerosis network and suggests feasibility for conducting clinical trials in this population.

Targeting protein homeostasis in sporadic inclusion body myositis.

Sporadic inclusion body myositis (sIBM) is the commonest severe myopathy in patients more than 50 years of age. Previous therapeutic trials have targeted the inflammatory features of sIBM but all have failed. Because protein dyshomeostasis may also play a role in sIBM, we tested the effects of targeting this feature of the disease. Using rat myoblast cultures, we found that up-regulation of the heat shock response with arimoclomol reduced key pathological markers of sIBM in vitro. Furthermore, in mutant valosin-containing protein (VCP) mice, which develop an inclusion body myopathy, treatment with arimoclomol ameliorated disease pathology and improved muscle function. We therefore evaluated arimoclomol in an investigator-led, randomized, double-blind, placebo-controlled, proof-of-concept trial in sIBM patients and showed that arimoclomol was safe and well tolerated. Although arimoclomol improved some IBM-like pathology in the mutant VCP mouse, we did not see statistically significant evidence of efficacy in the proof-of-concept patient trial.

Patterns of Weakness, Classification of Motor Neuron Disease, and Clinical Diagnosis of Sporadic Amyotrophic Lateral Sclerosis.

When approaching a patient with suspected motor neuron disease (MND), the pattern of weakness on examination helps distinguish MND from other diseases of peripheral nerves, the neuromuscular junction, or muscle. MND is a clinical diagnosis supported by findings on electrodiagnostic testing. MNDs exist on a spectrum, from a pure lower motor neuron to mixed upper and lower motor neuron to a pure upper motor neuron variant. Amyotrophic lateral sclerosis (ALS) is a progressive mixed upper and lower motor neuron disorder, most commonly sporadic, which is invariably fatal. This article describes a pattern approach to identifying MND and clinical features of sporadic ALS.

Symptom Management and End-of-Life Care in Amyotrophic Lateral Sclerosis.

The number of available symptomatic treatments has markedly enhanced the care of patients with amyotrophic lateral sclerosis (ALS). Once thought to be untreatable, patients with ALS today clearly benefit from multidisciplinary care. The impact of such care on the disease course, including rate of progression and mortality, has surpassed the treatment effects commonly sought in clinical drug trials. Unfortunately, there are few randomized controlled trials of medications or interventions addressing symptom management. In this review, the authors provide the level of evidence, when available, for each intervention that is currently considered standard of care by consensus opinion.

Disease course and therapeutic approach in dermatomyositis: A four-center retrospective study of 100 patients.

Dermatomyositis is a life-altering inflammatory disorder of skin and muscle. Details regarding the natural course of this disorder, the effects of specific therapies on its progression, and the optimal therapeutic dosage and duration of prednisone are limited. We performed a retrospective medical record review of dermatomyositis patients at four medical centers. All patients were over the age of 21 and had a clinical diagnosis of dermatomyositis with pathological confirmation. We reviewed average muscle strength, corticosteroid use, creatine kinase levels, and supplemental immunosuppressant use during the 36-month period following each patient's initial assessment. One hundred patients participated with an average age of 50.1 years. Average muscle strength improved and prednisone requirements lessened six months after initial assessment. There was no difference in the mean change in muscle strength or cumulative corticosteroid use over 36 months among those initially treated with methotrexate, mycophenolate mofetil, pulse IVIG, or azathioprine. There was a 5% mortality rate in dermatomyositis patients due to infections. Treated dermatomyositis patients demonstrate the most significant improvement in strength during the first six-to-twelve months following their initial clinical assessment. Additional prospective studies are needed to determine the relative benefit of select immunosuppressant agents in preserving strength and reducing corticosteroid use in dermatomyositis.

Pompe disease: literature review and case series.

Pompe disease is a rare multi-systemic metabolic myopathy caused by autosomal recessive mutations in the acidic alpha glucosidase (GAA) gene. Significant progress had been made in the diagnosis and management of patients with Pompe disease. Here, we describe our experience with 12 patients with various forms of Pompe disease including 4 potentially pathogenic, novel GAA variants. We also review the recent the recent advances in the pathogenesis, diagnosis, and treatment of individuals with Pompe disease.

Leg amyotrophic diplegia: prevalence and pattern of weakness at US neuromuscular centers.

OBJECTIVE: To identify the frequency of leg amyotrophic diplegia (LAD) at a US academic center, describe the pattern of weakness, and provide comparative data from 8 additional major US academic institutions. BACKGROUND: LAD is a leg onset variant of progressive muscular atrophy (PMA). LAD weakness is confined to the legs for at least 2 years, and there are no upper motor neuron signs. DESIGN/METHODS: We present a retrospective chart review of 24 patients with the LAD presentation from the University of Kansas Medical Center ( n = 8 cases) and from 8 US academic institutions (n = 16 cases). RESULTS: Of the 318 subjects identified in the University of Kansas Medical Center Neuromuscular Research Database, 82% (260 subjects) had amyotrophic lateral sclerosis (ALS), 1.9% (6) had familial ALS, 6.6% (21) had primary lateral sclerosis, and 9.2% (29) had lower motor neuron (LMN) disease. Of these 29 cases, 16 had PMA, 5 had brachial amyotrophic diplegia, while 8 had LAD. The mean LAD age of onset was 58 years with a male/female ratio of 3/1. Onset was asymmetric in 7/8. We identified a pelviperoneal pattern of weakness (sparing of knee extension and/or ankle plantar flexion) in 4 cases and distal predominant weakness in 3 cases. All patients had electrodiagnostic findings consistent with motor neuron disease confined to the lower extremities. We present LAD disease duration and survival data from 8 major academic neuromuscular centers. At last follow-up, weakness progressed to involve the arms in 6/24 LAD cases and of these 6 cases, 2 patients died from progression to typical ALS. From onset of symptoms, mean survival in LAD is 87 months, with 92% of cases being alive. CONCLUSIONS/RELEVANCE: The natural history of LAD differs from typical forms of ALS and PMA. LAD is a slowly progressive disorder that accounts for a fourth of LMN disease cases. An asymmetric pelviperoneal pattern of weakness should heighten the suspicion for LAD.

Facial onset sensorimotor neuronopathy syndrome: a case series.

OBJECTIVE: Facial onset sensorimotor neuronopathy (FOSMN) is a recently described neurological syndrome characterized by slow onset of facial sensory abnormalities and subsequent development of motor deficits. Except for 1 patient, FOSMN has so far been identified only in men. METHODS: We describe a case series of 3 women with FOSMN. We report their clinical, laboratory, and neurophysiological findings. RESULTS: The age of onset ranged from 39 to 72 years (mean, 60 years) with presentation 4-7 years after symptom onset. The first symptom was slowly progressive facial numbness, which was followed years later by dysphagia and impaired corneal reflexes. Dysarthria occurred in 2 patients, and mild arm weakness was noted in 2. Muscle stretch reflexes were increased in 1 patient, and in another case, arm sensation was reduced. Laboratory studies were unremarkable, and magnetic resonance imaging of the brain in 3 patients and of the cervical spine in 2 patients was normal. Nerve conduction studies showed reduced leg compound muscle action potential amplitudes in 1 patient and asymmetrically reduced arm sensory nerve action potentials in another case. In 2 patients, electromyography showed widespread active denervation in arm muscles in conjunction with the involvement of leg muscles in 1 case and the tongue in the other patient. We identified chronic neurogenic motor unit action potentials in the genioglossus muscle of all 3 cases while facial EMG performed in case 3 showed similar findings. Blink reflexes were abnormal in all patients. We treated 1 patient with high-dose intravenous methylprednisolone followed by intravenous immunoglobulin without any improvement, and she required percutaneous endoscopic gastrostomy (PEG) tube placement. CONCLUSIONS: This is the first case series describing 3 women with the FOSMN syndrome. We expand phenotype of FOSMN to include upper motor neuron signs and normal arm sensory nerve action potentials.

Myasthenia gravis, thymoma, and intestinal pseudo-obstruction: a case report and review.

We report a 28-year-old man who presented with intestinal pseudo-obstruction as the initial manifestation of thymoma, myasthenia gravis, and dysautonomia. The patient's autoantibody profile was characteristic of this constellation of disorders, being positive for both muscle and ganglionic nicotinic acetylcholine receptor antibodies and striational antibody. Inflammatory cell infiltrates were found in the myenteric plexus of the stomach and small intestine. Review of 12 previously reported cases suggests that patients with both myasthenia gravis and dysautonomia in the context of thymoma respond poorly to therapy.