Transglutaminase 6 Antibodies in the Serum of Patients With Amyotrophic Lateral Sclerosis ONLINE FIRST

Importance  Celiac disease is an autoimmune disorder triggered by gluten in genetically predisposed individuals. Gluten sensitivity can cause neurologic manifestations, such as ataxia or neuropathy, with or without gastrointestinal symptoms. Many patients with gluten ataxia produce antibodies toward the newly identified neuronal transglutaminase 6 (TG6). Two case reports described patients initially diagnosed with amyotrophic lateral sclerosis (ALS) and ultimately with celiac disease who improved with a strict gluten-free diet.

Objective  To evaluate the prevalence of celiac disease–related antibodies and HLA antigen alleles, as well as TG6 antibodies, in patients with ALS and healthy individuals serving as controls to determine whether a neurologic presentation of a gluten-related disorder mimicking ALS might occur in some patients.

Design, Setting, and Participants  In a case-control study conducted in an ALS tertiary center, we measured serum levels of total IgA antibodies, IgA antibodies to transglutaminase 2 (TG2) and endomysium, as well as IgA and IgG antibodies to deamidated gliadine peptide and TG6 and performed HLA antigen genotyping in 150 consecutive patients with ALS and 115 healthy volunteers of similar age and sex. Participants did not have any known autoimmune or gastroenterologic disorder and were not receiving any immunomodulatory medications. The study was conducted from July 1, 2010, to December 31, 2012.

Main Outcomes and Measures  Antibody levels and frequency of individuals with abnormal antibody values as well as frequency of HLA antigen alleles were compared between patient and control groups.

Results  All patients and control group participants were seronegative to IgA antibodies to TG2, endomysium, and deamidated gliadine peptide. Twenty-three patients (15.3%) were seropositive to TG6 IgA antibodies as opposed to only 5 controls (4.3%) (P = .004). The patients seropositive for TG6 showed a classic picture of ALS, similar to that of seronegative patients. Fifty patients and 20 controls were tested for celiac disease–specific HLA antigen alleles; 13 of 22 TG6 IgA seropositive individuals (59.1%) were seropositive for celiac disease–related alleles compared with 8 (28.6%) of the 28 seronegative individuals (P = .04). Mean (SD) levels of IgA antibodies to TG2 were 1.78 (0.73) in patients and 1.58 (0.68) in controls (normal, <10). In a subset of study participants, mean levels of deamidated gliadin peptide autoantibodies were 7.46 (6.92) in patients and 6.08 (3.90) in controls (normal, <16). Mean levels of IgA antibodies to TG6 were 29.3 (30.1) in patients and 21.0 (27.4) in controls (P = .02; normal, <26).

Conclusions and Relevance  The data from this study indicate that, in certain cases, an ALS syndrome might be associated with autoimmunity and gluten sensitivity. Although the data are preliminary and need replication, gluten sensitivity is potentially treatable; therefore, this diagnostic challenge should not be overlooked

JAMA Neurology 2015

Bilateral globus pallidus stimulation for severe Tourette's syndrome: a double-blind, randomised crossover trial

Background

Deep brain stimulation (DBS) has been proposed as a treatment option for severe Tourette's syndrome on the basis of findings from open-label series and small double-blind trials. We aimed to further assess the safety and efficacy of bilateral globus pallidus internus (GPi) DBS in patient's with severe Tourette's syndrome.

Methods

In a randomised, double-blind, crossover trial, we recruited eligible patients (severe medically refractory Tourette's syndrome, age ≥20 years) from two clinics for tertiary movement disorders in the UK. Enrolled patients received surgery for GPi DBS and then were randomly assigned in a 1:1 ratio (computer-generated pairwise randomisation according to order of enrolment) to receive either stimulation on-first or stimulation off-first for 3 months, followed by a switch to the opposite condition for a further 3 month period. Patients and rating clinicians were masked to treatment allocation; an unmasked clinician was responsible for programming the stimulation. The primary endpoint was difference in Yale Global Tic Severity Scale (YGTSS) total score between the two blinded conditions, assessed with repeated measures ANOVA, in all patients who completed assessments during both blinded periods. After the end of the blinded crossover phase, all patients were offered continued DBS and continued to have open-label stimulation adjustments and objective assessments of tic severity until database lock 1 month after the final patient's final trial-related visit. This trial is registered with ClinicalTrials.gov, number NCT01647269.

Findings

Between Nov 5, 2009, and Oct 16, 2013, we enrolled 15 patients (11 men, four women; mean age 34·7 years [SD 10·0]). 14 patients were randomly assigned and 13 completed assessments in both blinded periods (seven in the on-first group, six in the off-first group). Mean YGTSS total score in these 13 patients was 87·9 (SD 9·2) at baseline, 80·7 (SD 12·0) for the off-stimulation period, and 68·3 (SD 18·6) for the on-stimulation period. Pairwise comparisons in YGTSS total scores after Bonferroni correction were significantly lower at the end of the on-stimulation period compared with the off-stimulation period, with a mean improvement of 12·4 points (95% CI 0·1–24·7, p=0·048), equivalent to a difference of 15·3% (95% CI 5·3–25·3). All 15 patients received stimulation in the open-label phase. Overall, three serious adverse events occurred (two infections in DBS hardware at 2 and 7 weeks postoperatively, and one episode of deep-brain-stimulation-induced hypomania during the blinded on-stimulation period); all three resolved with treatment.

Interpretation

GPi stimulation led to a significant improvement in tic severity, with an overall acceptable safety profile. Future research should concentrate on identifying the most effective target for DBS to control both tics and associated comorbidities, and further clarify factors that predict individual patient response.

Neurology 2015

Perampanel efficacy and tolerability with enzyme-inducing AEDs in patients with epilepsy

Objective: Evaluate the impact of concomitant enzyme (CYP3A4)-inducer antiepileptic drugs (EIAEDs) on the efficacy and safety of perampanel in patients from the 3 phase-III clinical trials.

Methods: Patients with pharmacoresistant partial-onset seizures in the 3 phase-III clinical studies were aged 12 years and older and receiving 1 to 3 concomitant antiepileptic drugs. Following 6-week baseline, patients were randomized to once-daily, double-blind treatment with placebo or perampanel 8 or 12 mg (studies 304 and 305) or placebo or perampanel 2, 4, or 8 mg (study 306).

Results: Treatment response assessed by median percent reduction in seizure frequency and responder rates improved with perampanel compared with placebo. However, at 8 and 12 mg, the treatment response was significantly greater in patients receiving non-EIAEDs. The treatment effect (perampanel–placebo) also demonstrated a dose-dependent increase in all patients. The overall incidence of treatment-emergent adverse events was similar regardless of the presence of EIAEDs. Occurrence of some adverse events, such as fatigue, somnolence, dizziness, irritability, was greater in patients receiving non-EIAEDs, as was discontinuation because of adverse events.

Conclusions: Perampanel shows efficacy and safety in the presence and absence of EIAEDs. As systemic exposure to perampanel increases, so does efficacy. Given the extensive metabolism of perampanel, systemic exposure is clearly reduced with concomitant administration of CYP3A4 inducers. This supports the strategy of dosing perampanel to clinical effect. Recognition of these pharmacokinetic interactions will be important in the optimization of this novel medication.

Classification of evidence: This study provides Class II evidence that 2 to 12 mg/d doses of perampanel reduced seizure frequency and improved responder rate in the presence and absence of EIAEDs.

Neurology 2015

Polyneuropathy improvement following autologous stem cell transplantation for POEMS syndrome

Objective: To study the evolution of the neuropathy and long-term disability in a large cohort of patients with POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes) syndrome following autologous stem cell transplantation (ASCT).

Methods: Retrospective chart review documenting the clinical, electrophysiologic, and laboratory characteristics of patients with POEMS syndrome undergoing ASCT at Mayo Clinic, Rochester.

Results: Sixty patients with a median follow-up time of 61 months were studied. All patients had peripheral polyneuropathy and demonstrated neurologic improvement after ASCT (apart from one patient who died early). Before ASCT, 27 patients (45%) required a wheelchair and 17 (29%) required a walker or foot brace. At the end of the follow-up period, no patient was using a wheelchair and 23 patients (38%) were using a foot brace. The median Neuropathy Impairment Score improved from 66 to 48 points at 12 months and to 30 points at most recent follow-up (p < 0.0001). Median Rankin Scale score improved from 3 to 1.5 (p < 0.0001). Vascular endothelial growth factor levels decreased from a median of 452 to 63.5 pg/mL (p < 0.0001). The ulnar compound motor action potential amplitude (median) improved from 4.3 to 7.6 mV (p < 0.0001) and ulnar compound motor action potential conduction velocity (median) improved from 34 to 51 m/s (p < 0.0001). Predicted forced vital capacity improved from 81% to 88% (p < 0.0001). Periengraftment syndrome occurred in 24 patients. Fourteen patients required additional chemotherapy and/or radiation following ASCT, but there was no clinical deterioration in the neuropathy in any of these patients. Six patients died: 1 due to POEMS, 1 due to failed engraftment, and 4 due to other malignancies (2 myelodysplastic syndrome, 1 lymphoma, 1 metastatic lung cancer).

Conclusion: Patients with POEMS syndrome who undergo ASCT have a significant and meaningful improvement of their neuropathy by multiple measurements during both short and long-term follow-up, which corresponds to reduction in morbidity and disability (none are in wheelchair long-term). Periengraftment syndrome was common but manageable. Fatal complications, although rare, did occur, usually in association with other malignancies.

Classification of evidence: This study provides Class IV evidence that for patients with POEMS syndrome, ASCT improves neuropathy-related function

Neurology 2015.

Hemispheric cortical dysplasia secondary to a mosaic somatic mutation in MTOR

Objective: To define causative somatic mutations in resected brain tissue from an infant with intractable epilepsy secondary to hemispheric cortical dysplasia.

Methods: Whole-exome sequencing was conducted on genomic DNA derived from both resected brain tissue and peripheral blood leukocytes. Comparison of the brain vs blood sequencing results was performed using bioinformatic methods designed to detect low-frequency genetic variation between tissue pairs.

Results: Histopathology of the resected tissue showed dyslamination and dysmorphic neurons, but no balloon cells, consistent with focal cortical dysplasia type IIa. mTOR activation was observed by immunohistochemistry in the dysplasia. A missense mutation (c.4487T>G; p.W1456G) was detected in the FAT domain of MTOR in DNA from the dysplasia but not in lymphocytes. The mutation is predicted damaging (i.e., leading to mTOR activation) and was observed as a low-level mosaic with 8% of cells being heterozygous for the variant.

Conclusions: We report the novel finding of an MTOR mutation associated with nonsyndromic cortical dysplasia. Somatic-specific mutations in MTOR and related genes should be considered in a broader spectrum of patients with hemispheric malformations and more restricted forms of cortical dysplasia.

Neurology 2015

The surgically remediable syndrome of epilepsy associated with bottom-of-sulcus dysplasia

Objective: To determine clinical and EEG features that might help identify patients with epilepsy harboring small, intrinsically epileptogenic, surgically treatable, bottom-of-sulcus dysplasias (BOSDs).

Methods: Retrospective review of clinical records, EEG, MRI, and histopathology in 32 patients with drug-resistant epilepsy and MRI-positive (72% 3.0 tesla), pathologically proven (type 2B cortical dysplasia) BOSDs operated at our centers during 2005–2013.

Results: Localization of BOSDs was frontal in 19, insula in 5, parietal in 5, and temporal in 3, on the convexity or interhemispheric surfaces. BOSDs were missed on initial MRI at our centers in 22% of patients. Patients presented with focal seizures during infancy in 9, preschool years in 15, and school years in 8 (median age 5 years). Seizures were stereotyped, predominantly nocturnal, and typically nonconvulsive, with semiology referable to the fronto-central or perisylvian regions. Seizures occurred at high frequency during active periods, but often went into prolonged remission with carbamazepine or phenytoin. Intellect was normal or borderline, except in patients with seizure onset during infancy. Scalp EEG frequently revealed localized interictal epileptiform discharges and ictal rhythms. Patients underwent lesionectomy (median age 14 years) guided by electrocorticography and MRI, with prior intracranial EEG monitoring in only one patient. Twenty-eight patients (88%) became seizure-free, and 20 discontinued antiepileptic medication (median follow-up 4.1 years).

Conclusions: In patients with cryptogenic focal epilepsy, this clinical presentation and course should prompt review of or repeat MRI, looking for a BOSD in the frontal, parietal, or insula cortex. If a BOSD is identified, the patient might be considered for single-stage lesionectomy.

Neurology 2015

EFNS-ENS/EAN Guideline on concomitant use of cholinesterase inhibitors and memantine in moderate to severe Alzheimer’s disease

Background and purpose: Previous studies have indicated clinical benefits of a combination of cholinesterase inhibitors (ChEI) and memantine over ChEI monotherapy in Alzheimer’s disease (AD). Our objective was the development of guidelines on the question of whether combined ChEI/memantine treatment rather than ChEI alone should be used in patients with moderate to severe AD to improve global clinical impression (GCI), cognition, behaviour and activities of daily living (ADL). Methods: A systematic review and meta-analysis of randomized controlled trials based on a literature search in ALOIS, the register of the Cochrane Dementia and Cognitive Improvement Group, was carried out with subsequent guideline development according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Results: Pooled data from four trials including 1549 AD patients in the moderate to severe disease stage demonstrated significant beneficial effects of combination therapy compared to ChEI monotherapy for GCI [standardized mean difference (SMD) 0.20; 95% confidence interval (CI) 0.31; 0.09], cognitive functioning (SMD 0.27, 95% CI 0.37; 0.17) and behaviour (SMD 0.19; 95% CI 0.31; 0.07). The quality of evidence was high for behaviour, moderate for cognitive function and GCI and low for ADL. Agreement of panellists was reached after the second round of the consensus finding procedure. The desirable effects of combined ChEI and memantine treatment were considered to outweigh undesirable effects. The evidence was weak for cognition, GCI and ADL so that the general recommendation for using combination therapy was weak. Conclusions: We suggest the use of a combination of ChEI plus memantine rather than ChEI alone in patients with moderate to severe AD. The strength of this recommendation is weak.

Europeaan Journal Of Neurology 2015