Showing papers in "Journal of Neurology, Neurosurgery, and Psychiatry in 2012"

The syndrome of cognitive impairment in amyotrophic lateral sclerosis: a population-based study

Abstract: Background Despite considerable interest, the population-based frequency, clinical characteristics and natural history of cognitive impairment in amyotrophic lateral sclerosis (ALS) are not known. Methodology The authors undertook a prospective population-based study of cognitive function in 160 incident Irish ALS patients and 110 matched controls. Home-based visits were conducted to collect demographic and neuropsychological data. Patients were classified using the recently published consensus criteria and by a domain-based classification of both executive and non-executive cognitive processes. Results 13.8% of patients fulfilled the Neary criteria for frontotemporal dementia. In addition, 34.1% of ALS patients without evidence of dementia fulfilled the recently published consensus criteria for cognitive impairment. Non-demented ALS patients had a significantly higher frequency of impairment in language and memory domains compared to healthy controls. These deficits occurred primarily in patients with executive dysfunction. 14% of ALS patients had evidence of cognitive impairment without executive dysfunction, and no cognitive abnormality was detected in almost half the cohort (46.9%). Conclusion Co-morbid dementia occurs in approximately 14% of patients with a new diagnosis of ALS. Cognitive impairment, predominantly but not exclusively in the form executive dysfunction, is present in more than 40% of ALS patients who have no evidence of dementia. Cognitive impairment in ALS is not a universal feature, and its manifestations may be more heterogeneous than previously recognised.

Sporadic cerebral amyloid angiopathy revisited: recent insights into pathophysiology and clinical spectrum

Abstract: Sporadic cerebral amyloid angiopathy (CAA) is a common age related cerebral small vessel disease, characterised by progressive deposition of amyloid-β (Aβ) in the wall of small to medium sized arteries, arterioles and capillaries of the cerebral cortex and overlying leptomeninges. Previously considered to be a rare neurological curiosity, CAA is now recognised as an important cause of spontaneous intracerebral haemorrhage and cognitive impairment in the elderly, two fundamental challenges in the field of cerebrovascular disease. Our understanding of the pathophysiology and clinical manifestations of CAA continues to evolve rapidly, with the use of transgenic mouse models and advanced structural and/or molecular neuroimaging techniques. Yet, despite remarkable recent interest, CAA remains under-recognised by neurologists and stroke physicians. In this review, a fresh look at key developments in understanding the complex pathophysiology, important clinical and radiological features, diagnostic approaches and prospects for rational therapies for this enigmatic small vessel disorder is provided.

Depression: an inflammatory illness?

Abstract: Major depressive disorder (MDD) is associated with significant morbidity and mortality. Findings from preclinical and clinical studies suggest that psychiatric illnesses, particularly MDD, are associated with inflammatory processes. While it is unlikely that MDD is a primary ‘inflammatory’ disorder, there is now evidence to suggest that inflammation may play a subtle role in the pathophysiology of MDD. Most of the evidence that links inflammation to MDD comes from three observations: (a) one-third of those with major depression show elevated peripheral inflammatory biomarkers, even in the absence of a medical illness; (b) inflammatory illnesses are associated with greater rates of MDD; and (c) patients treated with cytokines are at greater risk of developing major depressive illness. We now know that the brain is not an immune privileged organ. Inflammatory mediators have been found to affect various substrates thought to be important in the aetiopathogenesis of MDD, including altered monoamine and glutamate neurotransmission, glucocorticoid receptor resistance and adult hippocampal neurogenesis. At a higher level, inflammation is thought to affect brain signalling patterns, cognition and the production of a constellation of symptoms, termed ‘sickness behaviour’. Inflammation may therefore play a role in the aetiology of depression, at least in a ‘cohort’ of vulnerable individuals. Inflammation may not only act as a precipitating factor that pushes a person into depression but also a perpetuating factor that may pose an obstacle to recovery. More importantly, inflammatory markers may aid in the diagnosis and prediction of treatment response, leading to the possibility of tailored treatments, thereby allowing stratification of what remains a heterogenous disorder.

When a minor head injury results in enduring symptoms: a prospective investigation of risk factors for postconcussional syndrome after mild traumatic brain injury.

Abstract: Objective A significant proportion (15–30%) of patients with mild traumatic brain injury (MTBI) are at risk of developing postconcussional syndrome (PCS). The aim of this study was to investigate the contributions of cognitive, emotional, behavioural and social factors to the development of PCS and identify early predictors. Methods A prospective cohort design was employed. 126 MTBI patients completed baseline questionnaire assessments within 2 weeks of the injury and 107 completed follow-up questionnaire assessments at 3 and 6 months. A series of self-report measures were used to assess cognitive, behavioural and emotional responses to MTBI. The primary outcome was the ICD-10 diagnosis for PCS. Demographic and clinical characteristic variables were compared between PCS cases and non-cases using independent sample t tests and χ 2 tests. Individual and multivariate logistic regression analyses were used to detect predictors of PCS. Results Of 107 MTBI patients, 24 (22%) met the criteria for PCS at 3 months and 22 (21%) at 6 months. Individual logistic regression analysis indicated that negative MTBI perceptions, stress, anxiety, depression and all-or-nothing behaviour were associated with the risk of PCS. Multivariate analysis revealed that all-or-nothing behaviour was the key predictor for the onset of PCS at 3 months while negative MTBI perceptions predicted PCS at 6 months. Conclusions The study provides good support for the proposed cognitive behavioural model. Patients9 perceptions of their head injury and their behavioural responses play important roles in the development of PCS, indicating that cognitive and behavioural factors may be potential targets for early preventive interventions.

Cognitive deficits following anti-NMDA receptor encephalitis

Abstract: Background Anti-NMDA receptor (NMDAR) encephalitis is a recently characterised autoimmune disorder mainly affecting young women. Although the clinical features of the acute disease are well characterised, cognitive long-term outcome has not been examined in detail. Methods The authors investigated cognitive performance in nine patients with proven anti-NMDAR encephalitis after recovery from the acute disease period (median 43 months after disease onset, range 23 to 69). Patients underwent a comprehensive neuropsychological assessment, including memory tasks that have previously been shown to be sensitive for hippocampal dysfunction. Results Substantial persistent cognitive impairments were observed in eight out of nine patients that mainly consisted of deficits in executive functions and memory. The severity of these deficits varied inter-individually. Patients with early immunotherapy performed significantly better. The most severe deficits were observed with inefficient or delayed initial treatment. Conclusion Our results suggest that cognitive deficits constitute a major long-term morbidity of anti-NMDAR encephalitis. These deficits relate to the distribution of NMDARs in the human brain and their functional role in normal cognition. Good cognitive long-term outcome may depend on early and aggressive treatment.

Charcot–Marie–Tooth disease: frequency of genetic subtypes and guidelines for genetic testing

Abstract: Background Charcot–Marie–Tooth disease (CMT) is a clinically and genetically heterogeneous group of diseases with approximately 45 different causative genes described. The aims of this study were to determine the frequency of different genes in a large cohort of patients with CMT and devise guidelines for genetic testing in practice. Methods The genes known to cause CMT were sequenced in 1607 patients with CMT (425 patients attending an inherited neuropathy clinic and 1182 patients whose DNA was sent to the authors for genetic testing) to determine the proportion of different subtypes in a UK population. Results A molecular diagnosis was achieved in 62.6% of patients with CMT attending the inherited neuropathy clinic; in 80.4% of patients with CMT1 (demyelinating CMT) and in 25.2% of those with CMT2 (axonal CMT). Mutations or rearrangements in PMP22 , GJB1 , MPZ and MFN2 accounted for over 90% of the molecular diagnoses while mutations in all other genes tested were rare. Conclusion Four commonly available genes account for over 90% of all CMT molecular diagnoses; a diagnostic algorithm is proposed based on these results for use in clinical practice. Any patient with CMT without a mutation in these four genes or with an unusual phenotype should be considered for referral for an expert opinion to maximise the chance of reaching a molecular diagnosis.

Central nervous system neuronal surface antibody associated syndromes: review and guidelines for recognition

Abstract: The concept of antibody mediated CNS disorders is relatively recent. The classical CNS paraneoplastic neurological syndromes are thought to be T cell mediated, and the onconeural antibodies merely biomarkers for the presence of the tumour. Thus it was thought that antibodies rarely, if ever, cause CNS disease. Over the past 10 years, identification of autoimmune forms of encephalitis with antibodies against neuronal surface antigens, particularly the voltage gated potassium channel complex proteins or the glutamate N-methyl-D-aspartate receptor, have shown that CNS disorders, often without associated tumours, can be antibody mediated and benefit from immunomodulatory therapies. The clinical spectrum of these diseases is not yet fully explored, there may be others yet to be discovered and some types of more common disorders (eg, epilepsy or psychosis) may prove to have an autoimmune basis. Here, the known conditions associated with neuronal surface antibodies are briefly reviewed, some general aspects of these syndromes are considered and guidelines that could help in the recognition of further disorders are suggested.

Large scale brain models of epilepsy: dynamics meets connectomics

Abstract: The brain is in a constant state of dynamic change, for example switching between cognitive and behavioural tasks, and between wakefulness and sleep. The brains of people with epilepsy have additional features to their dynamic repertoire, particularly the paroxysmal occurrence of seizures. Substantial effort over decades has produced a detailed description of many human epilepsies and of specific seizure types; in some instances there are known causes, sometimes highly specific such as single gene mutations, but the mechanisms of seizure onset and termination are not known. A large number of in vivo animal models and in vitro models based on animal tissues can generate seizures and seizure-like phenomena. Although in some instances there is much known about the mechanism of seizure onset and termination, across the range of models there is a bewildering range of mechanisms. There is a pressing need to bridge the gap between microscale mechanisms in experimental models and mechanisms of human epilepsies. Computational models of epilepsy have advanced rapidly, allowing dynamic mechanisms to be revealed in a computer model that can then be tested in biological systems. These models are typically simplified, leaving a need to scale up these models to the large scale brain networks in which seizures become manifest. The emerging science of connectomics provides an approach to understanding the large scale brain networks in which normal and abnormal brain functions operate. The stage is now set to couple dynamics with connectomics, to reveal the abnormal dynamics of brain networks which allow seizures to occur.

A randomised, double blind, placebo controlled trial with vitamin D3 as an add on treatment to interferon β-1b in patients with multiple sclerosis

Abstract: Objectives To study the safety and efficacy of vitamin D3 as an add on therapy to interferon β-1b (IFNB) in patients with multiple sclerosis (MS). Methods 1 year, double blind, placebo controlled, randomised study in 66 MS patients. The primary outcomes were T2 burden of disease (BOD) on MRI scans, proportion of patients with serum levels of 25-hydroxyvitamin D (25(OH)D) ≥85 nmol/l or intact parathyroid hormone (PTH) ≤20 ng/l, and number of adverse events. Secondary outcomes were number of MRI enhancing T1 lesions and new T2 lesions, annual relapse rate, changes in the Expanded Disability Status Scale score, timed 25 foot walk test and timed 10 foot tandem walk tests. Results Median change in BOD was 287 mm 3 in the placebo group and 83 mm 3 in the vitamin D group (p=0.105). Serum levels of 25(OH)D increased from a mean of 54 (range 19–82) nmol/l to 110 (range 67–163) nmol/l in the vitamin D group. 84% of patients reached a serum 25(OH)D level >85 nmol/l in the vitamin D group and 3% in the placebo group (p Conclusion Vitamin D3 add on treatment to IFNB reduces MRI disease activity in MS. Trial registration number EudraCT number 2007-001958-99 and ClinicalTrialsGov number NCT01339676.

Update on the pathophysiology and management of idiopathic intracranial hypertension

Abstract: Idiopathic intracranial hypertension is a disease of unknown aetiology, typically affecting young obese women, producing a syndrome of increased intracranial pressure without identifiable cause. Despite a large number of hypotheses and publications over the past decade, the aetiology is still unknown. Vitamin A metabolism, adipose tissue as an actively secreting endocrine tissue and cerebral venous abnormalities are areas of active study regarding the pathophysiology of idiopathic intracranial hypertension. There continues to be no evidence based consensus or formal guidelines regarding management and treatment of the disease. Treatment studies show that the diagnostic lumbar puncture is a valuable intervention beyond its diagnostic importance, and that weight management is critical. However, many questions remain regarding the efficacy of acetazolamide, CSF shunting procedures and cerebral transverse venous sinus stenting.

Diffusion tensor imaging studies of mild traumatic brain injury: a meta-analysis

Abstract: Objectives To assess the possibility that diffusion tensor imaging (DTI) can detect white matter damage in mild traumatic brain injury (mTBI) patients via systematic review and meta-analysis. Methods DTI studies that compared mTBI patients and controls were searched using MEDLINE, Web of Science, and EMBASE, (1980 through April 2012). Results A comprehensive literature search identified 28 DTI studies, of which 13 independent DTI studies of mTBI patients were eligible for the meta-analysis. Random effect model demonstrated significant fractional anisotropy (FA) reduction in the corpus callosum (CC) (p¼0.023, 95% CIs � 0.466 to � 0.035, 280 mTBIs and 244 controls) with no publication bias and minimum heterogeneity, and a significant increase in mean diffusivity (MD) (p¼0.015, 95% CIs 0.062 to 0.581, 154 mTBIs and 100 controls). Meta-analyses of the subregions of the CC demonstrated in the splenium FA was significantly reduced (p¼0.025, 95% CIs � 0.689 to � 0.046) and MD was significantly increased (p¼0.013, 95% CIs 0.113 to 0.950). FA was marginally reduced in the midbody (p¼0.099, 95% CIs � 0.404 to 0.034), and no significant change in FA (p¼0.421, 95% CIs � 0.537 to 0.224) and MD (p¼0.264, 95% CIs � 0.120 to 0.438) in the genu of the CC. Conclusions Our meta-analysis revealed the posterior part of the CC was more vulnerable to mTBI compared with the anterior part, and suggested the potential utility of DTI to detect white matter damage in the CC of mTBI patients.

Grey matter atrophy in cognitively impaired Parkinson's disease

Abstract: Objective Mild cognitive impairment and dementia are common non-motor features of Parkinson’s disease (PD). The aim of this study was to characterise grey matter changes associated with clearly defined stages of cognitive impairment in PD using structural MRI. Methods 96 PD subjects were classified using detailed cognitive testing as PD with normal cognition (PD-N, n¼57), PD with mild cognitive impairment (PD-MCI, n¼23) or PD with dementia (PD-D, n¼16); 34 controls matched for mean age and sex ratio also participated. Grey matter volume differences were evaluated using voxel based morphometry of grey matter segments derived from T1 weighted 3 T MRI, and multiple linear regression assessed the relationship between cognitive and motor impairments and grey matter concentration. Results Compared with controls, no grey matter differences were found in PD-N. PD-MCI showed limited grey matter atrophy in the temporal, parietal and frontal cortex as well as the bilateral caudal hippocampus, amygdala and right putamen. PD-D subjects exhibited far more extensive atrophy in regions involved in PD-MCI but also had reduced grey matter volume in other large areas of the temporal lobe (including the parahippocampi), the intracalcarine and lingual gyri, posterior cingulate gyrus, frontal regions and bilateral caudate. Grey matter loss in PD correlated with global cognitive score but not motor impairment in most of these regions. Interpretation Marked grey matter atrophy occurs in PD with dementia but far less extensive changes are evident in PD-MCI. Some grey matter atrophy precedes the development of dementia but may be accelerated once frank dementia begins.

MUltiple Sclerosis and Extract of Cannabis: results of the MUSEC trial

Abstract: Objective Multiple sclerosis (MS) is associated with chronic symptoms, including muscle stiffness, spasms, pain and insomnia. Here we report the results of the Multiple Sclerosis and Extract of Cannabis (MUSEC) study that aimed to substantiate the patient based findings of previous studies. Patients and methods Patients with stable MS at 22 UK centres were randomised to oral cannabis extract (CE) (N¼144) or placebo (N¼135), stratified by centre, walking ability and use of antispastic medication. This double blind, placebo controlled, phase III study had a screening period, a 2 week dose titration phase from 5 mg to a maximum of 25 mg of tetrahydrocannabinol daily and a 10 week maintenance phase. The primary outcome measure was a category rating scale (CRS) measuring patient reported change in muscle stiffness from baseline. Further CRSs assessed body pain, spasms and sleep quality. Three validated MS specific patient reported outcome measures assessed aspects of spasticity, physical and psychological impact, and walking ability. Results The rate of relief from muscle stiffness after 12 weeks was almost twice as high with CE than with placebo (29.4% vs 15.7%; OR 2.26; 95% CI 1.24 to 4.13; p¼0.004, one sided). Similar results were found after 4 weeks and 8 weeks, and also for all further CRSs. Results from the MS scales supported these findings. Conclusion The study met its primary objective to demonstrate the superiority of CE over placebo in the treatment of muscle stiffness in MS. This was supported by results for secondary efficacy variables. Adverse events in participants treated with CE were consistent with the known side effects of cannabinoids. No new safety concerns were observed. Trial registration number NCT00552604.

Medial temporal lobe epilepsy is associated with neuronal fibre loss and paradoxical increase in structural connectivity of limbic structures

Abstract: Background It has been hypothesised that seizure induced neuronal loss and axonal damage in medial temporal lobe epilepsy (MTLE) may lead to the development of aberrant connections between limbic structures and eventually result in the reorganisation of the limbic network. In this study, limbic structural connectivity in patients with MTLE was investigated, using diffusion tensor MRI, probabilistic tractography and graph theory based network analysis. Methods 12 patients with unilateral MTLE and hippocampal sclerosis (five left and seven right MTLE) and 26 healthy controls were studied. The connectivity of 10 bilateral limbic regions of interest was mapped with probabilistic tractography, and the probabilistic fibre density between each pair of regions was used as the measure of their weighted structural connectivity. Binary connectivity matrices were then obtained from the weighted connectivity matrix using a range of fixed density thresholds. Graph theory based properties of nodes (degree, local efficiency, clustering coefficient and betweenness centrality) and the network (global efficiency and average clustering coefficient) were calculated from the weight and binary connectivity matrices of each subject and compared between patients and controls. Results MTLE was associated with a regional reduction in fibre density compared with controls. Paradoxically, patients exhibited (1) increased limbic network clustering and (2) increased nodal efficiency, degree and clustering coefficient in the ipsilateral insula, superior temporal region and thalamus. There was also a significant reduction in clustering coefficient and efficiency of the ipsilateral hippocampus, accompanied by increased nodal degree. Conclusions These results suggest that MTLE is associated with reorganisation of the limbic system. These results corroborate the concept of MTLE as a network disease, and may contribute to the understanding of network excitability dynamics in epilepsy and MTLE.

The distal hereditary motor neuropathies

Abstract: The distal hereditary motor neuropathies (dHMN) comprise a heterogeneous group of diseases that share the common feature of a length-dependent predominantly motor neuropathy. Many forms of dHMN have minor sensory abnormalities and/or a significant upper-motor-neuron component, and there is often an overlap with the axonal forms of Charcot-Marie-Tooth disease (CMT2) and with juvenile forms of amyotrophic lateral sclerosis and hereditary spastic paraplegia. Eleven causative genes and four loci have been identified with autosomal dominant, recessive and X-linked patterns of inheritance. Despite advances in the identification of novel gene mutations, 80% of patients with dHMN have a mutation in an as-yet undiscovered gene. The causative genes have implicated proteins with diverse functions such as protein misfolding (HSPB1, HSPB8, BSCL2), RNA metabolism (IGHMBP2, SETX, GARS), axonal transport (HSPB1, DYNC1H1, DCTN1) and cation-channel dysfunction (ATP7A and TRPV4) in motor-nerve disease. This review will summarise the clinical features of the different subtypes of dHMN to help focus genetic testing for the practising clinician. It will also review the neuroscience that underpins our current understanding of how these mutations lead to a motor-specific neuropathy and highlight potential therapeutic strategies. An understanding of the functional consequences of gene mutations will become increasingly important with the advent of next-generation sequencing and the need to determine the pathogenicity of large amounts of individual genetic data.

Atypical, slowly progressive behavioural variant frontotemporal dementia associated with C9ORF72 hexanucleotide expansion

Abstract: Background Some patients meeting behavioural variant frontotemporal dementia (bvFTD) diagnostic criteria progress slowly and plateau at mild symptom severity. Such patients have mild neuropsychological and functional impairments, lack characteristic bvFTD brain atrophy and have thus been referred to as bvFTD ‘phenocopies’ or slowly progressive (bvFTD-SP). The few patients with bvFTD-SP that have been studied at autopsy have demonstrated no evidence of FTD pathology, suggesting that bvFTD-SP is neuropathologically distinct from other forms of FTD. Here, two patients with bvFTD-SP with chromosome 9 open reading frame 72 (C9ORF72) hexanucleotide expansions are described. Methods 384 patients with an FTD clinical spectrum and Alzheimer9s disease diagnoses were screened for C9ORF72 expansion. Two bvFTD-SP mutation carriers were identified. Neuropsychological and functional data, as well as brain atrophy patterns, assessed using voxel based morphometry (VBM), were compared with 44 patients with sporadic bvFTD and 85 healthy controls. Results Both patients were aged 48 years at baseline and met possible bvFTD criteria. In the first patient, VBM revealed thalamic and posterior insula atrophy. Over 7 years, his neuropsychological performance and brain atrophy remained stable. In the second patient, VBM revealed cortical atrophy with subtle frontal and insular volume loss. Over 2 years, her neuropsychological and functional scores as well as brain atrophy remained stable. Conclusions C9ORF72 mutations can present with a bvFTD-SP phenotype. Some bvFTD-SP patients may have neurodegenerative pathology, and C9ORF72 mutations should be considered in patients with bvFTD-SP and a family history of dementia or motor neuron disease.

Functional connectivity of dissociation in patients with psychogenic non-epileptic seizures

Abstract: Introduction Psychogenic non-epileptic seizures (PNES) resemble epileptic seizures, but lack epileptiform brain activity. Instead, the cause is assumed to be psychogenic. An abnormal coping strategy may be exhibited by PNES patients, as indicated by their increased tendency to dissociate. Investigation of resting-state networks may reveal altered routes of information and emotion processing in PNES patients. The authors therefore investigated whether PNES patients differ from healthy controls in their resting-state functional connectivity characteristics and whether these connections are associated with the tendency to dissociate. Methods 11 PNES patients without psychiatric comorbidity and 12 healthy controls underwent task-related paradigms (picture-encoding and Stroop paradigms) and resting-state functional MRI (rsfMRI). Global cognitive performance was tested using the Raven9s Matrices test and participants completed questionnaires for evaluating dissociation. Functional connectivity analysis on rsfMRI was based on seed regions extracted from task-related fMRI activation maps. Results The patients displayed a significantly lower cognitive performance and significantly higher dissociation scores. No significant differences were found between the picture-encoding and Stroop colour-naming activation maps between controls and patients with PNES. However, functional connectivity maps from the rsfMRI were statistically different. For PNES patients, stronger connectivity values between areas involved in emotion (insula), executive control (inferior frontal gyrus and parietal cortex) and movement (precentral sulcus) were observed, which were significantly associated with dissociation scores. Conclusion The abnormal, strong functional connectivity in PNES patients provides a neurophysiological correlate for the underlying psychoform and somatoform dissociation mechanism where emotion can influence executive control, resulting in altered motor function (eg, seizure-like episodes).

Long term lymphocyte reconstitution after alemtuzumab treatment of multiple sclerosis

Abstract: Background Alemtuzumab is a lymphocyte depleting monoclonal antibody that has demonstrated superior efficacy over interferon β-1a for relapsing–remitting multiple sclerosis (MS), and is currently under investigation in phase 3 trials. One unresolved issue is the duration and significance of the lymphopenia induced. The long term effects on lymphocyte reconstitution of a single course, and the consequences that this has on disability, morbidity, mortality and autoimmunity, were examined. Methods The lymphocyte reconstitution (n=36; 384 person years) and crude safety data (n=37; 447 person years) are reported for the first patients with progressive MS to receive alemtuzumab (1991–1997). Reconstitution time was expressed as a geometric mean or, when a non-negligible number of individuals failed to recover, as a median using survival analysis. Results Geometric mean recovery time (GMRT) of total lymphocyte counts to the lower limit of the normal range (LLN; ≥1.0×10 9 cells/l) was 12.7 months (95% CI 8.8 to 18.2 months). For B cells, GMRT to LLN (≥0.1×10 9 /l) was 7.1 months (95% CI 5.3 to 9.5); median recovery times for CD8 (LLN ≥0.2×10 9 cells/l) and CD4 lymphocytes (LLN ≥0.4×10 9 cells/l) were 20 months and 35 months, respectively. However, CD8 and CD4 counts recovered to baseline levels in only 30% and 21% of patients, respectively. No infective safety concerns arose during 447 person years of follow-up. Conclusions Lymphocyte counts recovered to LLN after a single course of alemtuzumab in approximately 8 months (B cells) and 3 years (T cell subsets), but usually did not recover to baseline values. However, this long lasting lymphopenia in patients with a previously normal immune system was not associated with an increased risk of serious opportunistic infection.

Natural history of transthyretin Val30Met familial amyloid polyneuropathy: analysis of late-onset cases from non-endemic areas.

Abstract: Objective The objective of this study was to elucidate the natural history of late-onset transthyretin Val30Met-associated familial amyloid polyneuropathy (FAP ATTR Val30Met) in non-endemic areas. Methods The authors retrospectively assessed the development of major clinical landmarks and abnormalities of nerve conduction and cardiac examination indices in 50 patients with an age of onset older than 50 years and no relationship to endemic foci. Results Once the neuropathic process was initiated, sensory and motor symptoms of both the upper and lower extremities appeared within a period of one and a half years. Digestive and orthostatic symptoms also tended to occur in the early phase of the disease, whereas urinary symptoms appeared in the middle of the disease progress. Along with pain in the extremities, these symptoms progressed over time and significantly disturbed the quality of life during the late phase of the disease, resulting in the need for wheelchair use. Although cardiomyopathy became clinically apparent only in the late phase of the disease, it was found to be the major cause of death. The mean duration of the disease onset to death was 7.3 years. Although values at the time of diagnosis were extremely variable, serial measurements of electrophysiological indices, the cardiothoracic ratio and interventricular septum thickness indicated a steady exacerbation in these outcomes among patients within a span of a couple of years. Conclusions The ages of onset of each clinical landmark were extremely variable between patients. However, once an initial symptom appeared, the chronological sequence of other clinical landmarks tended to be uniform, occurring within a relatively short time span.

Outcome and its predictors in Guillain–Barré syndrome

Abstract: Despite the use of plasma exchanges and intravenous immunoglobulins, Guillain-Barre syndrome (GBS) still carries non-negligible morbidity and mortality. Furthermore, the psychosocial consequences of GBS may persist longer than expected. Various aetiological, clinical, electrophysiological and immunological factors may carry prognostic predictive value. The objective of this article was to perform a summary of the current knowledge-base on outcome and its determinants in adequately-treated adult-onset GBS. Relevant prospective literature was reviewed through a Medline search of English-language articles published between 1966 and March 2012. GBS causes severe persistent disability in 14% of patients at 1 year. Loss of full strength, persistent pain and need for professional change occurs in about 40%. Mortality is of about 4% within the first year. Analysis of prognostic predictors consistently demonstrates the negative impact of higher age, preceding diarrhoea, greater disability/weaker muscles at admission, short interval between symptom-onset and admission, mechanical ventilation and absent/low amplitude compound muscle action potentials. Further outcome studies will soon be underway and may in future contribute to adequately integrate all potential factors in more reliable predictive models.

Diagnostic criteria for corticobasal syndrome: a comparative study

Abstract: Introduction There are no well-established criteria for patients with corticobasal syndrome. The authors have attempted to clarify this area by comparing and applying three sets of well-known criteria (from Toronto, the Mayo Clinic and Cambridge). Patient and methods The authors first compared the three criteria for overlap and differences, and then applied them to a group of 40 consecutive patients (22 men, mean age 67 years) with focal cortical syndrome characterised by apraxia and Parkinsonism, at both the early stages and later in their illness. Results Despite an overall similarity, there were major differences in the criteria which affect their applicability. Cognitive impairment was ubiquitous even at presentation, with speech and language impairment the commonest feature. Some classic features, alien limb and myoclonus, were present in a minority only even late in their course. The three criteria were equally applicable to patients with advanced disease (Toronto 92.5%, Cambridge 90% and Mayo 87.5%). Thirty patients (75%) satisfied all three criteria. Using this group as a ‘gold standard’, 73.3% fulfilled the Cambridge criteria at presentation compared with 46.7% and 36.7% for the Toronto and Mayo Clinic criteria, respectively. Concordance between criteria was poor. Conclusion Cognitive impairment, especially language impairment, was prominent from onset of disease. The Cambridge criteria apply to a higher proportion of cases at an early stage of corticobasal syndrome. The authors suggest a minor modification to capture the high prevalence of aphasia.

Fluorodeoxyglucose positron emission tomography in anti-N-methyl-D-aspartate receptor encephalitis: distinct pattern of disease

Abstract: Background Patients with encephalitis associated with antibodies against N-methyl-D-aspartate-receptor antibody (NMDAR-ab) encephalitis frequently show psychotic symptoms, amnesia, seizures and movement disorders. While brain MRI in NMDAR-ab encephalitis is often normal, abnormalities of cerebral glucose metabolism have been demonstrated by positron emission tomography (PET) with 18F-fluorodeoxyglucose(FDG) in a few usually isolated case reports. However, a common pattern of FDG-PET abnormalities has not been reported. Methods The authors retrospectively identified six patients with NMDAR-ab encephalitis in two large German centres who underwent at least one whole-body FDG-PET for tumour screening between January 2007 and July 2010. They analysed the pattern of cerebral uptake derived from whole-body PET data for characteristic changes of glucose metabolism compared with controls, and the changes of this pattern during the course of the disease. Results Groupwise analysis revealed that patients with NMDAR-ab encephalitis showed relative frontal and temporal glucose hypermetabolism associated with occipital hypometabolism. Cross-sectional analysis of the group demonstrated that the extent of these changes is positively associated with clinical disease severity. Longitudinal analysis of two cases showed normalisation of the pattern of cerebral glucose metabolism with recovery. Conclusions A characteristic change in cerebral glucose metabolism during NMDAR-ab encephalitis is an increased frontotemporal-to-occipital gradient. This pattern correlates with disease severity. Similar changes have been observed in psychosis induced by NMDAR antagonists. Thus, this pattern might be a consequence of impaired NMDAR function.

Improved detection of cortical MS lesions with phase-sensitive inversion recovery MRI

Abstract: Objective: Cortical grey matter lesions are common in multiple sclerosis (MS), but usually not seen on MRI. The authors compared the performance of double inversion recovery (DIR, currently considered the best available imaging sequence for detecting cortical lesions) with phase-sensitive inversion recovery (PSIR, a sequence allowing much higher resolution scans to be obtained in a clinically feasible time). Methods: Sixty MS patients and 30 healthy controls underwent MRI scanning on a 3 Tesla scanner. The authors compared intracortical (IC) and leucocortical (LC) lesion counts obtained with a standard DIR sequence (1×1×3 mm resolution, obtained in 4 min) and a PSIR sequence (0.5×0.5×2 mm, 11 min). Lesions were marked separately on DIR and PSIR scans. Results: In the whole MS cohort, more cortical lesions were seen on the higher-resolution PSIR than the DIR scans (IC mean±SD: 18.1±9.8 vs 5.9±4.5, p<0.001; LC mean±SD: 13.4±12.9 vs 7.3±8.0, p<0.001). On PSIR, ≥1 IC lesion was seen in 60/60 MS patients and 1/30 controls, and ≥1 LC lesion in 60/60 patients and 6/30 controls. On DIR, ≥1 IC lesion was seen in 50/60 patients and 0/30 controls, and ≥1 LC lesion(s) in 60/60 patients and 5/30 controls. Conclusions: Compared with DIR, using PSIR the authors are able to detect a significantly greater number of cortical grey matter lesions. The presence of at least one IC lesion in every MS patient, but very few healthy controls, suggests that it may be a useful adjunct to conventional MRI when a diagnosis of MS is suspected but not confirmed.

Different neurological and physiological profiles in POEMS syndrome and chronic inflammatory demyelinating polyneuropathy

Abstract: Background POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein and skin changes) syndrome, a rare cause of demyelinating neuropathy associated with multiorgan involvement, has been increasingly recognised. Polyneuropathy is often an initial manifestation and therefore the disorder can be misdiagnosed as chronic inflammatory demyelinating polyneuropathy (CIDP). Objective To elucidate whether POEMS syndrome and CIDP are differentiated based on profiles of neuropathy. Methods Clinical and electrophysiological data were reviewed in consecutive POEMS syndrome (n=51) and typical CIDP (n=46) patients in a single Japanese hospital between 2000 and 2010. Results Both POEMS and CIDP patients showed symmetric polyneuropathy, physiological evidence of demyelination (70% of POEMS patients fulfilled the electrodiagnostic criteria for definite CIDP) and albuminocytological dissociation; 49% of the POEMS syndrome patients had neuropathy onset and 60% of them were initially diagnosed as having CIDP by neurologists. Clinically, POEMS neuropathy more frequently showed severe leg pain (76% vs 7%; p Conclusions Before development of typical systemic manifestations, POEMS neuropathy can be distinguished from CIDP by the clinical profile and patterns of nerve conduction abnormalities. Recognition of these features leads to early diagnosis and proper treatment for POEMS syndrome.

Social Cognition and Emotional Assessment differentiates frontotemporal dementia from depression

Abstract: Background Behavioural variant of frontotemporal dementia (bvFTD) is a neurodegenerative disease that is clinically characterised by progressive behavioural changes and social interpersonal dysfunctions. Its diagnosis remains a clinical challenge, and depression is one of the main causes of misdiagnoses due to the prevalence of apathy in bvFTD. Objective To evaluate the sensitivity and specificity of the Social Cognition and Emotional Assessment (SEA) and the mini-SEA for differentiating bvFTD from major depressive disorder (MDD). Methods Scores for the SEA and mini-SEA for 37 patients with bvFTD (divided into subgroups of 17 with early bvFTD and 20 with moderate bvFTD according to the normal range of the Mattis Dementia Rating Scale), 19 MDD patients and 30 control subjects were compared to define the discrimination power of these tools compared with other standard neuropsychological tests. Results SEA and mini-SEA scores were significantly lower for both the early and moderate bvFTD groups compared with control subjects and the MDD group, and very few scores overlapped between patients in the bvFTD subgroups and patients in the MDD and control subgroups. SEA and mini-SEA scores distinguished early bvFTD from MDD with sensitivity and specificity rates above 94%. Conclusion Unlike standard executive neuropsychological tests, SEA and the mini-SEA can differentiate MDD from bvFTD in the early stages of the disease. The mini-SEA is an easy tool that can be utilised in neurological or psychiatric departments.

Population based study on patients with traumatic brain injury suggests increased risk of dementia

Abstract: Objective The relationship between traumatic brain injury (TBI) and the risk of dementia remains controversial. This population based study was designed to estimate and compare the risk of dementia in TBI and non-TBI individuals during the 5 year period after TBI. Methods This study was a retrospective cohort study. Data were obtained from the Longitudinal Health Insurance Database 2000. We included 44 925 patients receiving ambulatory or hospital care and 224 625 non-TBI patients; patients were matched for sex, age and year of index use of healthcare. Patients Results During the 5 year follow-up period, 1196 TBI (2.66%) and 224 625 non-TBI patients (1.53%) patients developed dementia. During the 5 year follow-up period, TBI was independently associated with a 1.68 (range 1.57–1.80) times greater risk of dementia after adjusting for sociodemographic characteristics and selected comorbidities. Conclusions The findings of this study suggest an increased risk of dementia among individuals with TBI. We suggest the need for more intensive medical monitoring and health education in individuals with TBI.

Relative mortality and survival in multiple sclerosis: findings from British Columbia, Canada

Abstract: Objective To examine mortality and factors associated with survival in a population based multiple sclerosis (MS) cohort. Methods Clinical and demographic data of MS patients registered with the British Columbia MS clinics (1980e2004) were linked to provincial death data, and patients were followed until death, emigration or study end (31 December 2007). Absolute survival and the influence of patient characteristics (sex, disease course (primary progressive (PPMS) vs relapsing onset (R-MS)) and onset age) were estimated by KaplaneMeier analyses (from birth and disease onset). Mortality relative to the general population was examined using standardised mortality ratios. Excess mortality associated with patient characteristics and time period of cohort entry was assessed by relative survival modelling. Results Of 6917 patients, 1025 died. Median survival age was 78.6 years (95% CI 77.5 to 79.7) for women and 74.3 years (95% CI 73.1 to 75.4) for men. Survival from onset was longer for R-MS (49.7 years; 95% CI 47.9 to 51.5) than for PPMS (32.5 years; 95% CI 29.5 to 35.7); however, survival age was similar. The overall standardised mortality ratios was 2.89 (95% CI 2.71 to 3.07), and patients survived approximately 6 years less than expected, relative to the general population. PPMS had a higher relative mortality risk compared with R-MS (relative mortality ratio (RMR) 1.52; 95% CI 1.30 to 1.80). Women with PPMS had a relative survival disadvantage compared with men with PPMS (RMR 1.55; 95% CI 1.19 to 2.01). Relative survival within 10 years of cohort entry was similar between time periods. Conclusions Some of the longest MS survival times are reported here but the risk of death was still greater than in the age, sex and calendar year matched general population. No evidence of increased survival over time was found when improved survival in the general population was taken into consideration.

The split hand syndrome in amyotrophic lateral sclerosis

Abstract: In amyotrophic lateral sclerosis (ALS), hand muscle wasting preferentially affects the 'thenar (lateral) hand', including the abductor pollicis brevis (APB) and first dorsal interosseous (FDI) muscles, with relative sparing of the hypothenar muscles (the abductor digiti minimi (ADM)). This peculiar pattern of dissociated atrophy of the intrinsic hand muscles is termed the 'split hand' and is rarely seen in diseases other than ALS. The muscles involved in the split hand are innervated through the same spinal segments (C8 and T1), and FDI and ADM, which are differentially affected, are both ulnar nerve innervated. The physiological mechanisms underlying the split hand in ALS are incompletely understood but both cortical and spinal/peripheral mechanisms are probably involved. Motor potentials evoked by magnetic stimulation are significantly smaller when recorded from the thenar complex, compared with the hypothenar muscles, supporting a cortical mechanism. But peripheral axonal excitability studies have suggested that APB/FDI motor axons have more prominent persistent sodium currents than ADM axons, leading to higher axonal excitability and thereby more ready degeneration. Pincer or precision grip is vital to human hand function, and frequent use of thenar complex muscles may lead to greater oxidative stress and metabolic demands at both upper and lower motoneurons innervating the APB and FDI. The split hand is a useful diagnostic sign in early ALS, and recent objective studies indicate that the sign has a high degree of specificity.

Structural MRI reveals cortical thinning in amyotrophic lateral sclerosis

Abstract: Objectives Amyotrophic lateral sclerosis (ALS) is a fatal disease characterised by combined upper and lower motor neuron degeneration. An early and accurate diagnosis is important for patient care and might facilitate the search for a more effective therapy. MRI was used to study the whole cortical mantle, applying an unbiased surface based approach to identify a marker of upper motor neuron involvement in ALS. Methods Surface based cortical morphology analyses were performed on structural, 3T MRI data of 45 patients with ALS and 25 matched healthy controls in a case control study design. These analyses consisted of measuring cortical thickness, surface area and volume. The effects of disease progression were examined by correlating cortical measures with progression rate and by longitudinal measures in 20 patients. Results Cortical morphology analyses revealed specific thinning in the precentral gyrus, considered the primary motor cortex, in patients with ALS compared with controls (p=6.3×10 −8 ). Surface area was reduced in the right inferior parietal region (p=0.049) and volume—the product of cortical thickness and surface area—was reduced in the right precentral gyrus (p=0.031). From these findings, it appears that cortical thickness is superior in detecting the degenerative effects of ALS. Relative cortical thinning in temporal regions was related to faster clinical progression (right inferior temporal gyrus: p=3.3×10 −4 ). Conclusions Cortical thinning of the primary motor cortex might be a diagnostic marker for upper motor neuron degeneration in ALS. Relative thinning in temporal regions was associated with a rapidly progressive disease course.

Ten year survival and outcomes in a prospective cohort of new onset Chinese Parkinson's disease patients

Abstract: Objective The 10 year outcomes and impact of motor and non-motor features on survival of a cohort of new onset Chinese Parkinson9s disease (PD) patients were prospectively studied. Method A cohort of new onset PD patients from 1995 to 2002 was recruited from a regional hospital based movement disorder clinic. Subjects were classified into postural instability gait disorder (PIGD), tremor predominant type or mixed subtypes at presentation. All were evaluated yearly for development of sensory complaints, first significant fall, hallucinations, dementia, postural hypotension, speech disturbances, dysphagia and postural instability persisted during ‘on’ medication state (PIPon). Mortality and predictors of death were determined. Results 171 new onset PD patients were recruited. After a mean follow-up of 11.3±2.6 years, 50 (29%) patients died. The standardised mortality ratio was 1.1 (CI 0.8 to 1.5, p=0.34). 83 (49%) developed dementia, 81 (47%) had psychosis and 103 (60%) had sensory complaints. Postural hypotension was found in 58 (34%) patients, 108 (63%) had PIPon, 101 (59%) had falls, 102 (60%) had dysphagia, 148 (87%) had freezing of gait and 117 (68%) had speech disturbances. 46 (27%) were institutionalised whereas 54 (32%) lived independently. Dementia (HR 5.0, 95% CI 2.1 to 13.0), PIPon (HR 2.8, 95% CI 1.2 to 6.8), older onset (HR 1.05, 1 year increase in age, 95% CI 1.0 to 1.1) and PIGD type (HR 2.1, 95% CI 1.2 to 3.7) were independent predictors of death. Conclusions 10 years into PD, a significant proportion of patients developed dopa resistant motor and non-motor features. Older onset, PIGD type, PIPon and dementia had a negative impact on survival. Standardised mortality ratio was 1.1.