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Background Environmental exposures are implicated in the etiology of amyotrophic lateral sclerosis (ALS). Application of insecticides, herbicides, and fungicides with neurotoxic properties to crops is permitted in the U.S., however reporting of the quantities is government mandated. Objective To identify pesticides that may be associated with ALS etiology for future study. Methods We geospatially estimated exposure to crop-applied pesticides as risk factors for ALS in a large de-identified medical claims database, the SYMPHONY Integrated Dataverse®. We extracted residence at diagnosis of ∼26,000 nationally distributed ALS patients, and matched non-ALS controls. We mapped county-level U.S. Geological Survey data on applications of 423 pesticides to estimate local residential exposure. We randomly broke the SYMPHONY dataset into two groups to form independent discovery and validation cohorts, then confirmed top hits using residential history information from a study of NH, VT, and OH. Results Pesticides with the largest positive statistically significant associations in both the discovery and the validation studies and evidence of neurotoxicity in the literature were the herbicides 2,4-D (OR 1.25 95 % CI 1.17–1.34) and glyphosate (OR 1.29 95 %CI 1.19–1.39), and the insecticides carbaryl (OR 1.32 95 %CI 1.23–1.42) and chlorpyrifos (OR 1.25 95 %CI 1.17–1.33). Significance Our geospatial analysis results support potential neurotoxic pesticide exposures as risk factors for sporadic ALS. Focused studies to assess these identified potential relationships are warranted.

A recent population-based analysis demonstrated lower risk of the lethal degenerative neuromuscular disease, amyotrophic lateral sclerosis (ALS) associated with history of the use of 'antineoplastic agents' and 'immunosuppressants'. To see if this finding was generalizable to other ALS cohorts, we examined associations between use of these agents and ALS risk in an independent case-control study of n = 414 ALS patients and n = 361 controls in an Eastern US population. Controls were sampled from the general population and among non-neurodegenerative disease patients. A history of chemotherapy treatment was significantly associated with a decreased ALS risk (OR 0.46, 95% CI 0.22-0.89, P = 0.026). We did not observe an association between risk of ALS and immunosuppressant therapy use (OR 0.78, 95% CI 0.50-1.02, P = 0.23). Analyses were adjusted for age, gender, and smoking. Our results support the prior report for chemotherapy treatment and lead to further discussion of the underlying mechanism.

Recently, it has been shown that proinflammatory cytokines play a complex and important role in the pathogenesis of many neurological disorders, including amyotrophic lateral sclerosis (ALS). To help facilitate future discoveries and more effective treatment strategies, we highlight the role that both innate and adaptive immune systems play in ALS and summarize the main observations that relate to cytokine expression levels in this disease. Furthermore, we propose a mechanism by which a known neurotoxin, β-N-methylamino-l-alanine (BMAA), may trigger this cytokine expression profile through motor neuron protein misfolding and subsequent NLRP3 (nucleotide-binding domain (NOD)-like receptor protein 3) inflammasome activation.

Objective – The aim of this study was to screen for and quantify the neurotoxic amino acid β-N-methylamino-l-alanine (BMAA) in a cohort of autopsy specimens taken from Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), Huntington’s disease (HD), and non-neurological controls. BMAA is produced by cyanobacteria found in a variety of freshwater, marine, and terrestrial habitats. The possibility of geographically broad human exposure to BMAA had been suggested by the discovery of BMAA in brain tissues of Chamorro patients with ALS/Parkinsonism dementia complex from Guam and more recently in AD patients from North America. These observations warranted an independent study of possible BMAA exposures outside of the Guam ecosystem. Methods – Postmortem brain specimens were taken from neuropathologically confirmed cases of 13 ALS, 12 AD, 8 HD patients, and 12 age-matched non-neurological controls. BMAA was quantified using a validated fluorescent HPLC method previously used to detect BMAA in patients from Guam. Tandem mass spectrometric (MS) analysis was carried out to confirm the identification of BMAA in neurological specimens. Results – We detected and quantified BMAA in neuroproteins from postmortem brain tissue of patients from the United States who died with sporadic AD and ALS but not HD. Incidental detections observed in two out of the 24 regions were analyzed from the controls. The concentrations of BMAA were below what had been reported previously in Chamarro ALS/ Parkinsonism dementia complex patients, but demonstrated a twofold range across disease and regional brain area comparisons. The presence of BMAA in these patients was confirmed by triple quadrupole liquid chromatography/mass spectrometry/mass spectrometry. Conclusions – The occurrence of BMAA in North American ALS and AD patients suggests the possibility of a gene/environment interaction, with BMAA triggering neurodegeneration in vulnerable individuals.

To evaluate the effect of SMN2 copy number on disease severity in spinal muscular atrophy (SMA), we stratified 45 adult SMA patients based on SMN2 copy number (3 vs. 4 copies). Patients with 3 copies had an earlier age of onset and lower spinal muscular atrophy functional rating scale (SMAFRS) scores and were more likely to be non-ambulatory. There was, however, no difference between the groups in quantitative muscle strength or pulmonary function testing. Functional scale may be a more discriminating outcome measure for SMA clinical trials.

Although the cyanobacteria/BMAA hypothesis of the cause of ALS and other age-related neurodegenerative diseases remains to be proven, it is not too early to ask whether treatment would be possible if the hypothesis were correct. This paper reviews the possible ways that chronic BMAA neurotoxicity could be prevented or treated.

We report the establishment of an in vivo model using the fruit fly Drosophila melanogaster to investigate the toxic effects of L-BMAA. We found that dietary intake of BMAA reduced the lifespan as well as the neurological functions of flies. Furthermore, we have developed an HPLC method to reliably detect both free and protein-bound BMAA in fly tissue extracts.

Veterans of the 1990-1991 Gulf War have been reported to have an increased incidence of amyotrophic lateral sclerosis (ALS) compared to personnel who were not deployed. An excess of ALS cases was diagnosed in Gulf War veterans younger than 45 years of age. Increased ALS among Gulf War veterans appears to be an outbreak time-limited to the decade following the Gulf War. Seeking to identify biologically plausible environmental exposures, we have focused on inhalation of cyanobacteria and cyanotoxins carried by dust in the Gulf region, particularly Qatar. Cyanobacterial crusts and mats are widespread in the deserts of Qatar, occupying up to 56% of the available area in some microhabitats. These cyanobacterial crusts, which help bind the desert sands, are dormant throughout most of the year, but during brief spring rains actively photosynthesize. When disturbed by vehicular traffic or other military activities, the dried crusts and mats can produce significant dust. Using HPLC/FD, an amino acid analyzer, UPLC/MS, and triple quadrupole LC/MS/MS we find that the dried crusts and mats contain neurotoxic cyanobacterial toxins, including beta-N-methylamino-L-alanine (BMAA) and 2,4 diaminobutyric acid (DAB). If dust containing cyanobacteria is inhaled, significant exposure to BMAA and other cyanotoxins may occur. We suggest that inhalation of BMAA, DAB, and other aerosolized cyanotoxins may constitute a significant risk factor for the development of ALS and other neurodegenerative diseases.

Background: TCH346 exerts antiapoptotic effects by binding to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and blocking the apoptotic pathway in which GAPDH is involved. Apoptosis is considered to be a key pathogenic mechanism in neurodegenerative diseases including ALS. Methods: Patients were randomly assigned in a double-blind fashion to receive either placebo or one of four doses of TCH346 (1.0, 2.5, 7.5, or 15 mg/day) administered orally once daily for at least 24 weeks. The primary outcome measure was the rate of change in the revised ALS functional rating scale (ALSFRS-R). The trial design included a 16-week lead-in phase to determine each patient9s rate of disease progression. The between treatment comparison was adjusted for the individual pretreatment rates of progression. The study was powered to detect a 25% reduction in the rate of decline of the ALSFRS-R as compared with placebo. Secondary outcome measures included survival, pulmonary function, and manual muscle testing (MMT). Results: Five hundred ninety-one patients were enrolled at 42 sites in Europe and North America. There were no differences in baseline variables. There were no significant differences between placebo and active treatment groups in the mean rate of decline of the ALSFRS-R or in the secondary outcome measures (survival, pulmonary function, and MMT). Conclusion: The trial revealed no evidence of a beneficial effect of TCH346 on disease progression in patients with ALS.

Cognitive impairment in patients with amyotrophic lateral sclerosis (ALS) is well documented, but behavioral abnormalities are not well defined. The Frontal Systems Behavior Scale (FrSBe) was used to assess changes in apathy, disinhibition, and executive dysfunction in 45 patients with ALS. Results suggest a high incidence of behavioral change, most notably in apathy associated with the onset of the disease and independent of mood. Apathy and verbal fluency were correlated, lending further support to the hypothesis that an underlying continuum exists between ALS and frontotemporal dementia (FTD), which is characterized predominantly by behavioral disturbance. The FrsBe is useful for detecting behavioral change and abnormalities in patients with ALS.

The chronic autoimmune neuropathies are a diverse group of disorders, whose diagnosis and classification is based on the clinical presentations and results of ancillary tests. In chronic inflammatory demyelinating polyneuropathy, controlled therapeutic trials demonstrated efficacy for intravenous gamma-globulins, corticosteroids, and plasmaphereis. In multifocal motor neuropathy, intravenous gamma-globulins have been shown to be effective. In the other immune-mediated neuropathies, there are no reported controlled therapeutic trials, but efficacy has been reported for some treatments in non-controlled trials on case studies. Choice of therapy in individual cases is based on reported efficacy, as well as severity, progression, coexisting illness, predisposition to developing complications, and potential drug interactions.

Despite numerous reports demonstrating mitochondrial abnormalities associated with amyotrophic lateral sclerosis (ALS), the role of mitochondrial dysfunction in the disease onset and progression remains unknown. The intrinsic mitochondrial apoptotic program is activated in the central nervous system of mouse models of ALS harboring mutant superoxide dismutase 1 protein. This is associated with the release of cytochrome-c from the mitochondrial intermembrane space and mitochondrial swelling. However, it is unclear if the observed mitochondrial changes are caused by the decreasing cellular viability or if these changes precede and actually trigger apoptosis. This article discusses the current evidence for mitochondrial involvement in familial and sporadic ALS and concludes that mitochondria is likely to be both a trigger and a target in ALS and that their demise is a critical step in the motor neuron death.

The time is now ripe for the ALS community in the United States to set up a national ALS Study Group. NIH and other granting agencies should fund a program to set up and run the ALS Study Group for five years renewable. This program should result in a competitive request for applications. The benefits likely to derive from a national ALS Study Group would include cheaper and more cost-effective clinical therapeutic trials, the development of better techniques for pilot trials, an increased number of potential new drugs brought from bench to bedside for ALS trials, increased research on biological and surrogate markers of disease, and increased physician-initiated research.

To test potentially beneficial drugs to amyotrophic lateral sclerosis (ALS), we created an ALS mouse model with a permeable blood-brain barrier, by crossing the G93A-SOD1 transgenic mouse with a multiple drug resistance type 1a/b (mdr1a/b) gene knockout mouse. To validate the model, we administered cyclosporine A intraperitoneally to the mice. Cyclosporine A accumulated in the brain and spinal cord of this mouse model, whereas it was unable to penetrate the CNS of mdr1a/b wild-type animals. Systemic administration of cyclosporine A extended the life of the double-mutant male mice by approximately 12%. Surprisingly, the effect was more robust in male mice and only marginal in female mice. These results demonstrate the usefulness of this combined mouse model for the testing of potentially therapeutic drugs and support the role of mitochondrial-mediated apoptosis in the pathway to motor neuron death in SOD1-associated ALS.

Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive and fatal motor neuron disease. We carried out two randomized, double-blind, placebo-controlled, multi-centre, multi-national studies with xaliproden (a drug with neurotrophic effect) to assess drug efficacy and safety at two doses. Patients with clinically probable or definite ALS of more than 6 months and less than 5 years duration were randomly assigned to placebo, 1 mg or 2 mg xaliproden orally once daily as monotherapy in Study 1 (n=867); or to the same regimen with addition of riluzole 50 mg bid background therapy in Study 2 (n=1210 patients). The two primary endpoints were defined as: 1. Time to death, tracheostomy, or permanent assisted ventilation (DTP), and 2. Time to vital capacity (VC)50% or DTP before (log-rank test) and after adjustment using a Cox proportional hazard model for prespecified prognostic factors. Secondary endpoints were rates of change of various functional measures. In Study 1, primary outcome measures did not reach statistical significance. For the 2 mg group, for time to VC50% analysis (without DTP) a significant 30% RRR was obtained (95% confidence interval [CI]: 8.46, P=0.009). In Study 2, no significant results were obtained. However, there was a trend in favour of add-on 1 mg dose xaliproden vs. placebo (RRR 15% [-6.31, ns] for time to VC50%; RRR 12% [CI: -6.27, ns] for time to VC50% or DTP). Adjusted RR ratios were consistently more favourable for the xaliproden groups. Tolerability was good, and dose-dependent side effects were largely associated with the serotonergic properties of xaliproden. An effect of xaliproden on functional parameters, especially VC, was noted. Although this effect did not reach statistical significance, xaliproden had a small effect on clinically noteworthy aspects of disease progression in ALS.

(2003). Psychosocial factors and cognition in amyotrophic lateral sclerosis. Amyotrophic Lateral Sclerosis and Other Motor Neuron Disorders: Vol. 4, No. 4, pp. 217-224.

The Wobbler mouse is recognized as an animal model for motoneuron disease that exhibits motoneuron pathology. We have recently demonstrated the occurrence of mitochondrial dysfunction in the Wobbler mouse brain. The aim of the present study was to evaluate whether mitochondrial dysfunction occurred at an early age at the time where disease symptoms appear, and whether it was more pronounced in the motor cortex or in the spinal cord. We report here a significant decrease in mitochondrial state 3 and 4 respiration rates at an early age in the Wobbler spinal cord. In addition, there was a pronounced decrease in oxidative phosphorylation in mitochondria isolated from both spinal cord and motor cortex in both age groups. This mitochondrial dysfunction was accompanied by impairment of complex I activity in mitochondria isolated from spinal cord at an early age. Decreases in complex III and IV activities were observed only in mitochondria isolated from the motor cortex at an early age, but impairment of complex III activity prevailed until later in the disease. We conclude that mitochondrial dysfunction ensues at an early stage of the disease and is more pronounced in the spinal cord, which correlates with previous studies that reported degeneration of spinal cord motorneurons.

We tested whether a regular exercise regimen was associated with a change in the life span of G93A-SOD1 transgenic mice, a model of familial ALS. Regular treadmill running for 10 weeks led to a significant increase in the life span of G93A-SOD1 mice. The effect was stronger in male mice, whereas there was only a trend between exercised and sedentary female G93A-SOD1 mice. The data suggest that regular exercise has a beneficial effect on the progression of ALS.

Cyanobacteria produce the neurotoxic amino acid β-N-methylamino-l-alanine (BMAA), which in contaminated marine waters has been found to accumulate in shellfish. Exposure to BMAA has been associated with an increased risk of neurodegenerative disease. Analysis of blinded samples found BMAA to be present in neuroproteins of individuals who died from ALS and ALS/PDC, but generally not in the brains of patients who died of causes unrelated to neurodegeneration or Huntington's disease, an autosomal dominant neurodegenerative disease. We here report support for a link between a patient with ALS and chronic exposure to the cyanobacterial neurotoxin BMAA via shellfish consumption. The patient had frequently eaten lobsters collected in Florida Bay for approximately 30 years. LC-MS/MS analysis of two lobsters which this ALS patient had placed in his freezer revealed BMAA at concentrations of 27 and 4 μg/g, respectively, as well as the presence of 2,4-diaminobutyric acid (DAB), a BMAA isomer. Two additional lobsters recently collected from Florida Bay also contained the neurotoxins BMAA and DAB. These data suggest that invertebrates collected in water where cyanobacterial blooms are present, if consumed, may result in direct human exposure to these neurotoxic amino acids. The data support the assertion that prolonged exposure to BMAA may have played a role in the etiology of ALS in this patient.

There is an imperative need for the early diagnosis of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND) in the current era of emerging treatments. When evaluating the patient with ALS/MND, the neurologist must consider a number of other motor neuron disorders and related motor syndromes that may have clinical features resembling ALS/MND. The revised Airlie House-El Escorial diagnostic criteria have been established through the consensus of experts meeting at workshops. However, by definition, using these criteria a patient is likely to have fairly advanced disease at the time of a definitive ALS/MND diagnosis. The reasons for the difficulty in making an early ALS/MND diagnosis are several. No surrogate diagnostic marker currently exists for ALS/MND. ALS/MND at its onset is heterogeneous in clinical presentation, its clinical course is variable, and several clinical variants are recognized. In addition, certain motor syndromes, such as monomelic amyotrophy, postpolio muscular atrophy, and multifocal motor neuropathy, can clinically mimic ALS/MND. Therefore, not only may the diagnosis of ALS/MND be clinically missed in the early stages, but worse, the patient may be wrongly labeled as having ALS/MND. The diagnosis of ALS/MND requires a combination of upper motor neuron (UMN) and lower motor neuron (LMN) involvement. Motor syndromes in which the deficit is restricted to the UMN or LMN through the entire course of the disease are described as atypical MND in this review. Approximately 5% of patients with ALS/MND have overt dementia with a characteristic frontal affect. ALS/MND with parkinsonism and dementia is rare outside the western Pacific region. The clinical course of motor disorder in these overlap syndromes does not differ from that in typical ALS/MND.

Mission statement. The Quality Standards Subcommittee (QSS) of the American Academy of Neurology (AAN) is charged with developing practice parameters for physicians. This evidence-based review addresses some of the major management issues in patients with ALS, and highlights the many areas in which more research is needed. ALS is a progressive, degenerative motor neuron disease of unknown cause. Muscle atrophy and spasticity in limb and bulbar muscles result in weakness and loss of ambulation, oropharyngeal dysfunction, weight loss, and ultimately respiratory failure. Although advances in understanding the pathophysiology of ALS have stimulated the development of new drug therapies,1 the mainstay of treatment for ALS patients remains symptomatic management. The practice parameters presented here comprise the first recommendations for the management of ALS based on a prescribed review and analysis of the peer-reviewed literature. These practice parameters were developed to improve the care and the quality of life of people with ALS by providing a rational basis for managing the disease. A multidisciplinary task force, all with extensive ALS experience, included 19 physicians, 3 patients with ALS, 1 gastroenterologist, 1 pulmonologist, 1 occupational therapist whose mother has ALS, and 1 nurse. In addition, consultants with expertise on ethics, practice parameter development, and medical library research participated in the process. The task force agreed to investigate five areas: 1) informing the patient and the family about the diagnosis and prognosis (also called “breaking the news”) of ALS; 2) symptomatic treatment; 3) nutrition, and decisions about percutaneous endoscopic gastroscopy (PEG); 4) respiratory insufficiency and mechanical ventilation; and 5) advance directives and palliative care. To help achieve this goal, they developed several guiding principles or attributes of care: Principles of ALS management

A computer model of denervation and complete reinnervation in skeletal muscle was originally developed for the purpose of furthering an understanding of the underlying mechanisms of motor unit reorganization in neurogenic diseases. We now describe its successor, a computer model for investigating different rates of denervation and reinnervation, as well as incomplete reinnervation. The new model introduces the concept of permanent denervation and features enhanced interactive control over the distribution of motor unit centers and additional measures of dispersion and co-dispersion of muscle fibers. The use of this model for investigating pathophysiologically significant issues in denervating diseases is illustrated pathophysiologically significant issues in denervating diseases is illustrated with five different sets of parameters. These simulate some of the processes that may be operational in chronic spinal muscular atrophy, amyotrophic lateral sclerosis, and progressive postpolio muscular dystrophy. The enhanced model will allow in-depth analysis of the influence of hypothesized pathophysiological processes on clinical, electrophysiological and pathological outcomes in human disease. © 1993 John Wiley & Sons, Inc.

Dr. Theodore Leon Munsat (Ted) died on Friday, November 22, at home in Waltham, Massachusetts, from complications of vasculitis, surrounded by his loving family.

Excitement about neurogenetics in the last two decades has diverted attention from environmental causes of sporadic ALS. Fifty years ago endemic foci of ALS with a frequency one hundred times that in the rest of the world attracted attention since they offered the possibility of finding the cause for non-endemic ALS throughout the world. Research on Guam suggested that ALS, Parkinson's disease and dementia (the ALS/PDC complex) was due to a neurotoxic non-protein amino acid, beta-methylamino-L-alanine (BMAA), in the seeds of the cycad Cycas micronesica. Recent discoveries that found that BMAA is produced by symbiotic cyanobacteria within specialized roots of the cycads; that the concentration of protein-bound BMAA is up to a hundred-fold greater than free BMAA in the seeds and flour; that various animals forage on the seeds (flying foxes, pigs, deer), leading to biomagnification up the food chain in Guam; and that protein-bound BMAA occurs in the brains of Guamanians dying of ALS/PDC (average concentration 627 microg/g, 5 mM) but not in control brains have rekindled interest in BMAA as a possible trigger for Guamanian ALS/PDC. Perhaps most intriguing is the finding that BMAA is present in brain tissues of North American patients who had died of Alzheimer's disease (average concentration 95 microg/g, 0.8mM); this suggests a possible etiological role for BMAA in non-Guamanian neurodegenerative diseases. Cyanobacteria are ubiquitous throughout the world, so it is possible that all humans are exposed to low amounts of cyanobacterial BMAA, that protein-bound BMAA in human brains is a reservoir for chronic neurotoxicity, and that cyanobacterial BMAA is a major cause of progressive neurodegenerative diseases including ALS worldwide. Though Montine et al., using different HPLC method and assay techniques from those used by Cox and colleagues, were unable to reproduce the findings of Murch et al., Mash and colleagues using the original techniques of Murch et al. have recently confirmed the presence of protein-bound BMAA in the brains of North American patients dying with ALS and Alzheimer's disease (concentrations100 microg/g) but not in the brains of non-neurological controls or Huntington's disease. We hypothesize that individuals who develop neurodegenerations may have a genetic susceptibility because of inability to prevent BMAA accumulation in brain proteins and that the particular pattern of neurodegeneration that develops depends on the polygenic background of the individual.

Biological markers play an important role in the development of the understanding of a disease, its diagnosis and treatment. This is particularly true of amyotrophic lateral sclerosis (ALS) at this time. We need better biological markers for the diagnosis, for improved understanding of the underlying pathogenetic mechanisms, and for assistance in new drug development. This review of currently available biological and surrogate markers in ALS discusses novel approaches to the use of such markers, and new drugs for the treatment of ALS.

The lack of effective therapy for many of the chronic neuromuscular diseases such as amyotrophic lateral sclerosis, hereditary motor sensory neuropathy (Charcot-Marie-Tooth disease), spinocerebellar degenerations and idiopathic polyneuropathy has led to a search for substances that may stimulate peripheral nerve regeneration. Two such agents that have been proposed are gangliosides (mixed purified bovine brain gangliosides, Cronassial) and thyrotropin releasing factor (TRH). Studies on both of these agents were initially reported with enthusiasm to be successful, but later double-blind controlled studies have failed to confirm these findings. This review provides critical analysis of the designs of studies of potentially effective agents in chronic neuromuscular diseases, and emphasizes the power of the placebo response, and the importance of designing placebos which are indistinguishable from the trial medication other than in the active effect.

Experienced neurologists caring for patients with amyotrophic lateral sclerosis (ALS) have commented that these patients commonly exhibit similar personality features. Previous research studies on the premorbid personality characteristics of ALS patients have however not clearly substantiated this observation. In the present study, caregivers of newly diagnosed ALS patients provided ratings of patients' premorbid personality traits, and these ratings were compared with those of caregivers of patients newly diagnosed with other chronic, progressive diseases. Results indicated that ALS patients were rated as significantly lower than the other medical patients in the Openness trait on the NEO‐Personality Inventory. This finding is discussed in relation to past research findings, prevailing clinical characterizations of ALS patients, and current research on cognitive and behavioral changes in ALS.

The time is now ripe for the ALS community in the United States to set up a national ALS Study Group. The National Institutes of Health and other granting agencies should fund a program to set up and run the ALS Study Group for 5 years renewable. This program should result in a competitive request for applications. The benefits likely to derive from a national ALS Study Group would include cheaper and more cost-effective clinical therapeutic trials, the development of better techniques for pilot trials, an increased number of potential new drugs brought from bench to bedside for ALS trials, increased research on biological and surrogate markers of disease, and increased physician-initiated research.

In the aftermath of World War II, U.S. Army physicians in Guam found an unusual paralytic disease among the indigenous Chamorro people of Guam and nearby islands in the Pacific Ocean. Some villager...

Dear Sir,We reported the results of a phase I study of hyperbaric oxygen therapy (HBOT) in amyotrophic lateral sclerosis (ALS) in this journal in 2004 [1]. Although that report described a pilot st...

Painful distal sensory polyneuropathy (DSP) is the most common peripheral neuropathy in patients with human immunodeficiency virus-1 (HIV-1) infection. There is no specific therapy for DSP, and nonspecific treatment with pain blockers and narcotic agents generally fails to adequately control the symptoms. We report two patients who had subacute painful neuropathy in the B2 (formerly AIDS-related complex [ARC]) stage of HIV-1 infection. Neurophysiologic studies revealed predominantly axonal sensorimotor neuropathy. Sural nerve biopsy in both cases showed a necrotizing vasculitis. Treatment with corticosteroids resulted in rapid relief of pain, followed by arrest of the neuropathic process. Although not previously emphasized, vasculitic neuropathy must be considered among the treatable causes of painful sensory neuropathy in HIV-1-infected individuals. NEUROLOGY 1996;47: 1446-1451

A number of facts about ALS are unquestionable. We need more effective drugs to treat the disease. The disease is remarkably variable in its site of involvement and rate of progression from patienttopatient.Ifadrugarrestedprogressionofthedisease,or even reversed it, we would only need one patient to prove this. Unfortunately, current expectations are for the discovery of drugs that only slow the progression. Until now, clinical trials of a drug that has laboratory features suggesting a likely effect on motor neuron death have proceeded along the classical path: phase 1 clinical trials designed to show that the drug is safe; phase 2 trials in ALS patients who show some possible clinical benefit; and phase 3 double blind, randomized, placebo controlledtrialsthatinvolve300patientspertreatmentarm,oreven more, and cost at least $20 million, the cost depending on the amount ofdata collected.Unfortunately,although todate many trials have been undertaken, only those involving Riluzole have unequivocally proved the positive effect of the drug. 1‐3 There has been much research into ways of speeding the process of identifying new drugs for ALS. Recent work has been devoted to trials in murine models of ALS, and in the rapid screening of potential drugs in motor neuron-like cultures. The question of the use of placebo controlled trials in ALS and in other lethaldiseases continues tobe a topicfordiscussion. From thepatient’spoint ofview, if thereisa drugthatmight producea benefit, he wants it now and does not want a trial involving a placebo. This attitude is counter-intuitive in that an unstudied drug is of untried efficacy, and cannot be classed as a therapy. However, patients with ALS are not interested in scientific proof that a drug works, but rather whether they can live longer. This is as true in ALS as it is for cancer and AIDS. Physicians looking after these dire diseases are among the most caring of our profession, and often have the same psychological drive to treat the patient to the exclusion of finding out if the drug actually helps or even hurts the patient. The latter is always possible. For instance, in the Regeneron high dose CNTF trial, patients treated with theactivedrugdeteriorated fasterthanthosetreated with the placebo. 4 For a number of years after that trial was published, the clamor for avoidance of placebo-controlled trials was muted, though we are now back in an era when ALS patients try to obtain every drug that is even suggested to be worthy of trial. Munsat and colleagues showed that Z-scores of data from a populationofALSpatientsdecreasedlinearly,andthattherewas a similar trend in individual patients.5 The implication of their work was that therapeutic trials in ALS could be designed to compare an active treatment group with a database from patients in an observational, natural history study. This would greatly reduce the cost the trial, and avoid some patients having to take a placebo. Unfortunately, this has not proved to be the case. Comparison of the placebo groups in the various controlled ALS trials in the last decade has shown significant differences, presumably derived from different inclusion and exclusion criteria, and the demographic details of the patients. Alternative trial designs allow the patient to act as his own control.Across-overdesigninALSiscomplicatedbythefactthat the patient is more advanced by the time of the cross-over. This might be avoided by collecting data during a natural history phase preceding an active treatment phase. However, this presupposesthatdiseaseprogressionislinearinbothphases,witha similar slope ofdeterioration on thecriticalmeasure,andso still needs a placebo arm if the placebo response is to be avoided. In this issue of the Journal, Bryan et al. revisit the question of the elimination of a placebo arm in ALS trials. 6 Based on data fromtheplacebogroupinthenegativelowdoseCNTFtrial, 7 the authors compare the rate of deterioration during the 3 month ‘‘lead-in’’ or natural history phase with that during the 6-month treatment phase. The authors report that the rate of decrease in FVC was significantly faster in the placebo phase than in the preceding natural history phase, casting doubt on the underlying theory of this type of study. Moreover, there was no correlation between the two phases of the study for the slopes of the leg and FVC megascores. There was a small but significant correlation between the deterioration in the two phases in the arm scores, indicating a smaller variation in the arm data, a fact previously reported. 8 The authors suggest that comparison with natural history database controls might allow exploratory trials to rule out ineffective treatments. They recommend the use of arm strength measurements in such trials. However, they indicate that double-blind placebo controlled trials are still needed to prove drug efficacy and to study safety of potential drugs for ALS, a point I have previously advocated.9 Until we have more effective drugs for the treatment of ALS, trial design will remain an important area of discussion. 3,10‐11

Previous reports of primary lumbosacral plexopathy (LSP) have stressed the benign nature of the syndrome. No effective treatment is known for the occasional patients who do not recover or who have relapses. We report two patients presenting with a progressive form of idiopathic LSP. Both patients showed remarkable improvement on high-dose intravenous immunoglobulin therapy. We suggest that these patients represent a treatable subgroup of LSP.

A patient with inclusion body myositis (IBM) is presented. Unusual aspects of this case include a myopathy of 36 years duration, severe dysphagia due to cricopharyngeus muscle dysfunction, improvement with cricopharyngeus myotomy, and a diagnostic cricopharyngeus muscle biopsy.

There is growing evidence that idiopathic chronic inflammatory demyelinating polyneuropathy (CIDP) and polyneuropathy in patients with diabetes mellitus (DM) that meets the electrophysiological criteria for CIDP (DM-CIDP) have many similarities.To evaluate whether DM-CIDP responds to intravenous immunoglobulin (IVIG) therapy.Twenty-six patients (mean [SD] age, 64 [8.9] years; age range, 40-80 years) with type 2 DM (n = 25), who met the electrophysiological criteria for CIDP, were given IVIG therapy (400 mg/kg body weight per day for 5 days) in a prospective open-label pilot study. All patients had quantitative evaluation using the Neuropathy Impairment Score at baseline and at the end of 4 weeks from the initiation of IVIG therapy.The mean Neuropathy Impairment Score improved significantly from baseline (mean [SD], 61.5 [26.0] points) to the end of the fourth week (33 [29.6] points; P.00l). This clinically significant improvement occurred in 21 (80.8%) of the 26 patients. Conduction block occurred in 11 (42.3%) of the 26 patients; improvement in the Neuropathy Impairment Score was more frequent in patients who had a conduction block (11 of 11 patients) than in those who did not (10/15 [66.7%]; P =.03). Adverse reactions to IVIG included reversible renal dysfunction in 3 patients, flulike symptoms in 5, headache in 5, and chest pain and shortness of breath in 1.Although IVIG therapy seemed to improve DM-CIDP in this uncontrolled trial, a controlled trial is required for confirmation of our findings.

Background Recent studies have reported that patients with diabetes mellitus (DM) have a predisposition to develop chronic inflammatory demyelinating polyneuropathy (CIDP). Objectives To determine whether patients with DM have a polyneuropathy fulfilling electrophysiologic criteria for CIDP, and whether CIDP is more frequent in patients with type 1 than in patients with type 2 DM. Methods We prospectively studied the frequency of electrophysiologic changes meeting the criteria for CIDP in patients with DM seen in our electrophysiology laboratory during a 51-month period (period 1). To evaluate the relationship between DM and CIDP, we prospectively determined during a 14-month period (period 2) the frequency of DM in patients seen in our electrophysiology laboratory with other neuromuscular diseases, and the frequency of idiopathic CIDP. Results During period 1, 120 patients with DM met the electrophysiologic criteria for CIDP (DM-CIDP). The most frequent clinical features of DM-CIDP were those of a predominantly large-fiber sensorimotor neuropathy, with recent motor deterioration and a moderately increased cerebrospinal fluid protein concentration. Twenty-six of the 120 patients were given intravenous immunoglobulin (400 mg/kg per day for 5 days), and 21 patients (80.8%) had significant improvement in the neurologic deficit at the end of 4 weeks of therapy. The DM-CIDP occurred equally in type 1 and type 2 DM. During period 2, 1127 patients were seen. Of these, 189 (16.8%) had DM with various neurologic disorders, including 32 patients (16.9%) with DM-CIDP. Among the remaining 938 patients without DM, 17 (1.8%) had idiopathic CIDP. The odds of occurrence of DM-CIDP was 11 times higher among diabetic than nondiabetic patients (P Conclusions Demyelinating neuropathy meeting the electrophysiologic criteria for CIDP occurred in both types of DM, and its occurrence was significantly higher in diabetic than in nondiabetic patients.

We examined the immunopathology and the expression of human immunodeficiency virus type 1 (HIV-1) in lumbosacral dorsal root ganglia (DRGs) from 16 patients with acquired immunodeficiency syndrome (AIDS) and 10 HIV-1-seronegative controls. Using in situ hybridization, we detected HIV-1 RNA in a few perivascular cells in DRGs from five of 16 AIDS patients (31%). In addition, using polymerase chain reaction, we detected HIV-1 DNA more frequently in DRGs from four of five AIDS patients (80%) examined. We detected interleukin-6 (IL-6) immunoreactivity in endothelial cells in DRGs from seven of 16 AIDS patients (44%) but from none of 10 HIV-1-seronegative controls (0%). We found more nodules of Nageotte, CD8+ T lymphocytes, and intercellular adhesion molecule-1 (ICAM-1)-positive endothelial cells and mononuclear cells in DRGs from AIDS patients than in DRGs from controls. Increased numbers of nodules of Nageotte in DRGs of AIDS patients were associated with detection of HIV-1 RNA by in situ hybridization and detection of IL-6 by immunohistochemistry. We conclude that low levels of replication of HIV-1, through cytotoxic T lymphocytes or expression of cytokines, may play a role in the subclinical degeneration of sensory neurons frequently observed in DRGs of AIDS patients.