Frédéric Blanc

Diagnosis and management of dementia with Lewy bodies Fourth consensus report of the DLB Consortium

The Dementia with Lewy Bodies (DLB) Consortium has refined its recommendations about the clinical and pathologic diagnosis of DLB, updating the previous report, which has been in widespread use for the last decade. The revised DLB consensus criteria now distinguish clearly between clinical features and diagnostic biomarkers, and give guidance about optimal methods to establish and interpret these. Substantial new information has been incorporated about previously reported aspects of DLB, with increased diagnostic weighting given to REM sleep behavior disorder and 123iodine-metaiodobenzylguanidine (MIBG) myocardial scintigraphy. The diagnostic role of other neuroimaging, electrophysiologic, and laboratory investigations is also described. Minor modifications to pathologic methods and criteria are recommended to take account of Alzheimer disease neuropathologic change, to add previously omitted Lewy-related pathology categories, and to include assessments for substantia nigra neuronal loss. Recommendations about clinical management are largely based upon expert opinion since randomized controlled trials in DLB are few. Substantial progress has been made since the previous report in the detection and recognition of DLB as a common and important clinical disorder. During that period it has been incorporated into DSM-5, as major neurocognitive disorder with Lewy bodies. There remains a pressing need to understand the underlying neurobiology and pathophysiology of DLB, to develop and deliver clinical trials with both symptomatic and disease-modifying agents, and to help patients and carers worldwide to inform themselves about the disease, its prognosis, best available treatments, ongoing research, and how to get adequate support.

Neuromyelitis optica in France A multicenter study of 125 patients

Background: There have been few epidemiologic studies on neuromyelitis optica (NMO) and none used the recent 2006 diagnostic criteria. Here we describe the clinical, laboratory, MRI, and disability course of NMO in a French cohort of 125 patients. Methods: We performed an observational, retrospective, multicenter study. Data were collected from September 2007 through August 2008, corresponding to the endpoint of the study. We identified 125 patients fulfilling the 2006 NMO criteria. Selection was made using hospital files and a specific clinical questionnaire for NMO. Results: Mean age at onset was 34.5 years (range 4–66) with a mean disease duration of 10 ± 7.8 years at the endpoint. The patients were mainly (87%) Caucasian, with a female:male ratio of 3:1. In 90% of cases, the association of optic neuritis, longitudinal extensive myelitis, and a Paty-negative initial brain MRI was sufficient to fulfill the supportive criteria. Eighty-eight percent of patients were treated with immunosuppressive therapies. Median delay from onset to Expanded Disability Status Scale (EDSS) score 4 was 7 years; score 6, 10 years; and score 7, 21 years. The first episode of myelitis was immediately followed by an EDSS score ≥4 in 37.3% of cases, and a severe residual visual loss was observed in 22% of patients after the first episode of optic neuritis. Multivariate analysis did not reveal any predictors of a poor evolution other than a high number of MRI brain lesions at diagnosis, which were predictive of a residual visual acuity ≤1/10. Conclusions: Our demographic data provide new data on disability in patients with neuromyelitis optica, most of whom were receiving treatment.

RELEVANCE OF THE ANTIBODY INDEX TO DIAGNOSE LYME NEUROBORRELIOSIS AMONG SEROPOSITIVE PATIENTS

Background: No consensual criteria exist to diagnose neuroborreliosis. The intrathecal anti-Borrelia antibody index (AI) is a necessary criterion to diagnose neuroborreliosis in Europe, but not in the United States. Previous studies to determine the diagnostic value of the AI found a sensitivity ranging from 55% to 80%. However, these studies included only typical clinical cases of meningitis or meningoradiculitis, and none had a control group with CSF anti-Borrelia antibodies. Methods: We studied a sample of 123 consecutive patients with clinical signs of neurologic involvement and CSF anti-Borrelia antibodies. We determined the AI for all patients and a final diagnosis was made. Patients were then divided into three groups (neuroborreliosis, possible neuroborreliosis, control). Results: Thirty of the 40 patients with neuroborreliosis had a positive AI (AI sensitivity = 75%). Two of the 74 patients with another neurologic diagnosis had a positive AI (AI specificity = 97%). Conclusion: The antibody index has a very good specificity but only moderate sensitivity. Given the lack of consensual criteria for neuroborreliosis and the absence of a “gold standard” diagnostic test, we propose pragmatic diagnostic criteria for neuroborreliosis, namely the presence of four of the following five items: no past history of neuroborreliosis, positive CSF ELISA serology, positive anti-Borrelia antibody index, favorable outcome after specific antibiotic treatment, and no differential diagnosis. These new criteria will need to be tested in a larger, prospective cohort.

Optical Coherence Tomography in Neuromyelitis Optica

BACKGROUND Neuromyelitis optica (NMO) is an inflammatory disease with combined features of optic neuritis and myelitis. This pathologic entity may induce severe disability, including visual loss and paraplegia. Other than clinical follow-up, there is no marker for severity of the disease. OBJECTIVES To evaluate the use of optical coherence tomography (OCT) in NMO and to determine whether this new technique could be a good marker of axonal loss in NMO. DESIGN Cross-sectional study. PARTICIPANTS Thirty-five patients with NMO or at a high risk for NMO (having optic neuritis or myelitis and who are positive for NMO antibody) were prospectively studied. Fifteen healthy individuals served as control subjects. MAIN OUTCOME MEASURE All patients underwent a complete ophthalmologic evaluation, including OCT, funduscopy, and visual field, visual acuity, and visual evoked potential testing. Expanded Disability Status Scale scores were assessed but without the visual data. Correlations between the visual test results and demographic or clinical characteristics were evaluated. RESULTS Optical coherence tomography and visual field data were available for only 32 patients because 3 patients were blind. The mean retinal nerve fiber layer thickness was significantly reduced in patients with NMO compared with controls (P < .001). We found good correlation between the OCT results and visual field testing. We also found weak correlation between OCT results and both visual acuity and visual evoked potential latencies. We did not find any correlation between OCT results and age, sex, or disease duration. In contrast, retinal nerve fiber layer thickness was closely correlated with the Expanded Disability Status Scale score (P < .001). CONCLUSIONS Optical coherence tomography results are significantly altered in patients with NMO. Optical coherence tomography is easy to perform, and the results are well correlated with visual acuity and visual field findings. It could be considered a marker of axonal loss because we found good correlation between OCT and the Expanded Disability Status Scale score. These preliminary results will need to be confirmed in a longitudinal prospective study.

Is neuromyelitis optica associated with human leukocyte antigen

Background To establish whether or not multiple sclerosis (MS) and neuromyelitis optica (NMO) are different pathological entities, we wondered whether MS patients and NMO patients share the same pattern of human leukocyte antigen (HLA) predisposition. Objective To study a putative association between susceptibility to NMO and HLA class I or class II loci in Caucasians. Methods A total of 39 unrelated Caucasian patients with NMO and six patients at a high risk of converting to NMO were studied. DNA genotyping of HLA class I and class II loci was assessed and allelic frequencies were reported at a high-resolution level. A case-control study by comparing the allelic distribution in the NMO patients with that of a French Caucasian MS group and a French Caucasian healthy group was carried out. Results The frequencies of HLA-DQA1, DQB1, and HLA-DRB1 DR2 alleles in the NMO group were intermediate between the healthy control group and the MS group. The DPB1*0501 allele was not increased in the NMO group compared with the healthy control group. The distribution of HLA-DRB1 allele enabled to distinguish between NMO-IgG-positive patients and healthy controls (P = 0.01). NMO-IgG-negative patients presented an HLA II pattern closer to that of the MS group (P = 0.01). Conclusion In contrast to the reported results in Asian opticospinal MS, we found no association between the DPB1*0501 allele and NMO in our Caucasian patients. Moreover, we suggest that NMO-IgG-positive patients could represent a distinct NMO group in terms of their genetic susceptibility.

Cognitive Functions in Neuromyelitis Optica

BACKGROUND Neuromyelitis optica (NMO) is characterized by optic neuritis and longitudinally extensive acute transverse myelitis. The brain is generally considered healthy in NMO, though very recent studies have demonstrated that magnetic resonance imaging abnormalities may be observed in various brain regions of NMO patients. To date, cognitive functions have never been investigated in NMO. OBJECTIVE To investigate cognitive functions in a cohort of 30 patients with NMO. DESIGN Observational, prospective study. PATIENTS We studied 30 patients with NMO and compared them with 30 patients with multiple sclerosis and 30 healthy controls matched for age, sex, and educational level. Main Outcome Measure We applied a French translation of the Brief Repeatable Battery of Neuropsychological Tests for Multiple Sclerosis and 3 additional tests. RESULTS Cognitive performance was significantly lower in the NMO and multiple sclerosis groups than in healthy controls for the 2-second (P< .001) and 3-second (P= .001) Paced Auditory Serial Addition Test, the digit symbol modality test (P= .005), word generation (P= .02), and forward (P= .002) and backward (P= .007) digit span test. We did not observe any difference in test performance between NMO and multiple sclerosis patients. We found no differences between the 3 groups for the other tests. We did not find any correlation between clinical, biological, or magnetic resonance imaging results and cognitive dysfunction. CONCLUSIONS This study confirms the recent concept of a possible brain involvement in NMO. Additional studies are needed to confirm these initial results and to better understand the mechanisms of such abnormalities.

Cognitive function in radiologically isolated syndrome.

Background: Radiologically isolated syndrome (RIS) is characterized by patients with asymptomatic T2 hypersignals detected by brain MRI fulfilling dissemination in space criteria and is suggestive of subclinical multiple sclerosis (MS). In previous studies, it was demonstrated that visual evoked potential and cerebrospinal fluid help to identify pejorative markers in converting to MS. Objective: To date the cognitive function has never been investigated in a cohort of RIS. The objective of this study was to investigate cognitive function in a cohort of 26 RIS patients. Methods: We prospectively assessed the BCcogSEP (a French adaptation of the Brief Repeatable Battery (BRB) including eight cognitive tests) of 26 patients with RIS, compared with 26 MS patients and 26 healthy subjects matched for age, sex and level of education. Results: When comparing the three groups, the cognitive performance was significantly lower in the RIS and MS groups compared with healthy subjects for the Paced Auditory Serial Addition Test (PASAT) 3 seconds (p = 0.002), phonemic fluencies (p = 0.02), the code of the WAIS (p = 0.05), the direct (p = 0.002) or indirect (p = 0.007) digit span test, the cross-taping test (p = 0.019) and Go—No-Go (p = 0.001). When we compared RIS and MS, the cognitive performance was significantly lower in MS patients for the direct span number (p = 0.003) and cross-tapping test (p = 0.05). We did not find significant differences between the three groups for the other tests. We did not find a correlation between clinical, biological and MRI results and cognitive dysfunctions. Conclusions: This study confirms the recently developed concept of RIS patients who present similar features to MS patients. Further studies are necessary to confirm these initial results and to correlate cognitive disorders with MRI surrogate markers.

Long-term follow-up of neuromyelitis optica with a pediatric onset

Background: Neuromyelitis optica (NMO) is a rare inflammatory disease. Average age at onset is 35 years. Few data exist on patients with pediatric-onset NMO (p-NMO), with disease onset before age 18 years. We report the clinical and paraclinical features and long-term outcome of patients with p-NMO and compare them with a large adult-onset NMO (a-NMO) cohort. Methods: We performed a retrospective, multicenter study of patients with p-NMO in pediatric and adult medical centers. We identified 125 patients with NMO (12 p-NMO; 113 a-NMO) fulfilling the 2006 criteria. Data were collected using hospital files and standardized assessment forms for NMO. Results: Patients with p-NMO were followed up during a mean 19.3 years. Median age at onset was 14.5 years (4.1–17.9) with a female:male ratio of 3:1. Three patients (25%) fulfilled Paty criteria for multiple sclerosis on first brain MRI, including one patient with acute disseminated encephalomyelitis. Median interval between onset and residual Expanded Disability Status Scale (EDSS) score 4 was 20.7 years, score 6 was 26 years, and score 7 was 28.7 years. Median interval between onset and residual visual loss ≤1/10 was 1.3 years. Compared with a-NMO, p-NMO showed a longer time to EDSS scores 4 and 6, largely explained by the severity of the first myelitis in the a-NMO group. Time to first treatment was longer in the p-NMO group (13.1 vs 3.4 years). Conclusion: Patients with p-NMO can present a diffuse inflammatory process on first brain MRI and have a longer time to disability than patients with a-NMO.

C9ORF72 Repeat Expansions in the Frontotemporal Dementias Spectrum of Diseases: A Flow-chart for Genetic Testing

Frontotemporal dementia (FTD) refers to a disease spectrum including the behavioral variant FTD (bvFTD), primary progressive aphasia (PPA), progressive supranuclear palsy/corticobasal degeneration syndrome (PSP/CBDS), and FTD with amyotrophic lateral sclerosis (FTD-ALS). A GGGGCC expansion in C9ORF72 is a major cause of FTD and ALS. C9ORF72 was analyzed in 833 bvFTD, FTD-ALS, PPA, and PSP/CBDS probands; 202 patients from 151 families carried an expansion. C9ORF72 expansions were much more frequent in the large subgroup of patients with familial FTD-ALS (65.9%) than in those with pure FTD (12.8%); they were even more frequent than in familial pure ALS, according to estimated frequencies in the literature (23-50%). The frequency of carriers in non-familial FTD-ALS (12.7%) indicates that C9ORF72 should be analyzed even when family history is negative. Mutations were detected in 6.8% of PPA patients, and in 3.2% of patients with a clinical phenotype of PSP, thus enlarging the phenotype spectrum of C9ORF72. Onset was later in C9ORF72 (57.4 years, 95%CI: 55.9-56.1) than in MAPT patients (46.8, 95%CI: 43.0-50.6; p = 0.00001) and the same as in PGRN patients (59.6 years; 95%CI: 57.6-61.7; p = 0.4). ALS was more frequent in C9ORF72 than in MAPT and PGRN patients; onset before age 50 and parkinsonism were indicative of MAPT mutations, whereas hallucinations were indicative of PGRN mutations; prioritization of genetic testing is thus possible. Penetrance was age- and gender-dependent: by age 50, 78% of male carriers were symptomatic, but only 52% of females. This can also guide genetic testing and counseling. A flowchart for genetic testing is thus proposed.

Natural history of adult-onset eIF2B-related disorders: a multi-centric survey of 16 cases

Mutations in one of the five eukaryotic initiation factor 2B genes (EIF2B1-5) were first described in childhood ataxia with cerebral hypomyelination--vanishing white matter syndrome. The syndrome is characterized by (i) cerebellar and pyramidal signs in children aged 2-5 years; (ii) extensive cavitating leucoencephalopathy; and (iii) episodes of rapid deterioration following stress. Since then a broad clinical spectrum from congenital to adult-onset forms has been reported, leading to the concept of eIF2B-related disorders. Our aim was to describe clinical and brain magnetic resonance imaging characteristics, genetic findings and natural history of patients with adult-onset eIF2B-related disorders (after age 16). The inclusion criteria were based on the presence of eIF2B mutations and a disease onset after the age of 16 years. One patient with an asymptomatic diagnosis (age 16 years) was also included. Clinical and magnetic resonance findings were retrospectively recorded in all patients. All patients were examined to assess clinical evolution, using functional, pyramidal, cerebellar and cognitive scales. This multi-centric study included 16 patients from 14 families. A sex ratio imbalance was noted (male/female = 3/13). The mean age of onset was 31.1 years (range 16-62). Initial symptoms were neurologic (n = 11), psychiatric (n = 2) and ovarian failure (n = 2). Onset of the symptoms was linked to a precipitating factor in 13% of cases that included minor head trauma and delivery. During follow-up (mean: 11.2 years, range 2-22 years) 12.5% of the patients died. Of the 14 survivors, 62% showed a decline in their cognitive functions, and 79% were severely handicapped or bedridden. One case remained asymptomatic. Stress worsened clinical symptoms in 38% of the patients. Magnetic resonance imaging findings consist of constant cerebral atrophy, extensive cystic leucoencephalopathy (81%), corpus callosum (69%) and cerebellar (38%) T2-weighted hyperintensities. All families except one showed mutations in the EIF2B5 gene. The recurrent p.Arg113His-eIF2Bepsilon mutation was found in 79% of the 14 eIF2B-mutated families, mainly at a homozygous state. The family with a mutation in EIF2B2 had the relatively prevalent p.Glu213Gly mutation. eIF2B-related disorder is probably underestimated as an adult-onset inherited leucoencephalopathy. In this late-onset form, presentation ranges from neurologic symptoms to psychiatric manifestations or primary ovarian failure. Cerebral atrophy is constant, whereas the typical vanishing of the white matter can be absent. Functional and/or cognitive prognosis remains severe. Molecular diagnosis is facilitated for these forms by the screening of the two recurrent p.Arg113His-eIF2Bepsilon and p.Glu213Gly-eIF2Bbeta mutations, positive in 86% of cases.