A novel CCM2 variant in a family with non-progressive cognitive complaints and cerebral microbleeds

Lobar cerebral microbleeds are most often sporadic and associated with Alzheimer's disease. The aim of our study was to identify the underlying genetic defect in a family with cognitive complaints and multiple lobar microbleeds and a positive family history for early onset Alzheimer's disease. We performed exome sequencing followed by Sanger sequencing for validation purposes on genomic DNA of three siblings with cognitive complaints, reduced amyloid-beta-42 in CSF and multiple cerebral lobar microbleeds. We checked for the occurrence of the variant in a cohort of 363 patients with early onset dementia and/or microbleeds. A novel frameshift variant (c.236_237delAC) generating a premature stop codon in the CCM2 gene shared by all three siblings was identified. Pathogenicity of the variant was supported by the presence of cerebral cavernous malformations in two of the siblings and by the absence of the variant exome variant databases. Two siblings were homozygous for APOE-ϵ4; one heterozygous. The cognitive complaints, reduced amyloid-beta-42 in CSF and microbleeds suggest preclinical Alzheimer's disease, but the stability of the cognitive complaints does not. We hypothesize that the phenotype in this family may be due to a combination of the CCM2 variant and the APOE status. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc

Rare Genetic Variant in SORL1 May Increase Penetrance of Alzheimer's Disease in a Family with Several Generations of APOE-ɛ4 Homozygosity

BACKGROUND: The major genetic risk factor for late onset Alzheimer's disease (AD) is the APOE-ɛ4 allele. However, APOE-ɛ4 homozygosity is not fully penetrant, suggesting co-occurrence of additional genetic variants. OBJECTIVE: To identify genetic factors that, next to APOE-ɛ4 homozygosity, contribute to the development of AD. METHODS: We identified a family with nine AD patients spanning four generations, with an inheritance pattern suggestive of autosomal dominant AD, with no variants in PSEN1, PSEN2, or APP. We collected DNA from four affected and seven unaffected family members and performed exome sequencing on DNA from three affected and one unaffected family members. RESULTS: All affected family members were homozygous for the APOE-ɛ4 allele. Statistical analysis revealed that AD onset in this family was significantly earlier than could be expected based on APOE genotype and gender. Next to APOE-ɛ4 homozygosity, we found that all four affected family members carried a rare variant in the VPS10 domain of the SORL1 gene, associated with AβPP processing and AD risk. Furthermore, three of four affected family members carried a rare variant in the TSHZ3 gene, also associated with AβPP processing. Affected family members presented between 61 and 74 years, with variable presence of microbleeds/cerebral amyloid angiopathy and electroencephalographic abnormalities. CONCLUSION: We hypothesize that next to APOE-ɛ4 homozygosity, impaired SORL1 protein function, and possibly impaired TSHZ3 function, further disturbed Aβ processing. The convergence of these genetic factors over several generations might clarify the increased AD penetrance and the autosomal dominant-like inheritance pattern of AD as observed in this family

A novel CCM2 variant in a family with non-progressive cognitive complaints and cerebral microbleeds

Lobar cerebral microbleeds are most often sporadic and associated with Alzheimer's disease. The aim of our study was to identify the underlying genetic defect in a family with cognitive complaints and multiple lobar microbleeds and a positive family history for early onset Alzheimer's disease. We performed exome sequencing followed by Sanger sequencing for validation purposes on genomic DNA of three siblings with cognitive complaints, reduced amyloid-beta-42 in CSF and multiple cerebral lobar microbleeds. We checked for the occurrence of the variant in a cohort of 363 patients with early onset dementia and/or microbleeds. A novel frameshift variant (c.236_237delAC) generating a premature stop codon in the CCM2 gene shared by all three siblings was identified. Pathogenicity of the variant was supported by the presence of cerebral cavernous malformations in two of the siblings and by the absence of the variant exome variant databases. Two siblings were homozygous for APOE-ε4; one heterozygous. The cognitive complaints, reduced amyloid-beta-42 in CSF and microbleeds suggest preclinical Alzheimer's disease, but the stability of the cognitive complaints does not. We hypothesize that the phenotype in this family may be due to a combination of the CCM2 variant and the APOE status

A Decade of Genetic Counseling in Frontotemporal Dementia Affected Families: Few Counseling Requests and much Familial Opposition to Testing

A decade of genetic counseling of frontotemporal dementia (FTD) affected families has generated two important observations. First, the uptake rate for presymptomatic testing for FTD is low in our department of Clinical Genetics at the Erasmus Medical Center in the Netherlands. Second, FTD at-risk counselees reported substantial familial opposition to genetic testing, which is distinct from the attitude in Huntington Disease affected families. We hypothesize that the low acceptance for FTD genetic counseling is consequential to the familial opposition and explain this within the theoretical framework of separation-individuation. Furthermore, we hypothesize that separation-individuation problems do not similarly influence the acceptance of HD genetic counseling, due to the educative role of the well-organised patient organization for HD in the Netherlands. We offer counseling recommendations that serve to facilitate the individuation of the counselee with respect to the FTD genetic test

Resting state functional connectivity differences between behavioral variant frontotemporal dementia and Alzheimer's disease

Introduction: Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are the most common types of early-onset dementia. Early differentiation between both types of dementia may be challenging due to heterogeneity and overlap of symptoms. Here, we apply resting state functional magnetic resonance imaging (fMRI) to study functional brain connectivity differences between AD and bvFTD. Methods: We used resting state fMRI data of 31 AD patients, 25 bvFTD patients, and 29 controls from two centers specialized in dementia. We studied functional connectivity throughout the entire brain, applying two different analysis techniques, studying network-to-region and region-to-region connectivity. A general linear model approach was used to study group differences, while controlling for physiological noise, age, gender, study center, and regional gray matter volume. Results: Given gray matter differences, we observed decreased network-to-region connectivity in bvFTD between (a) lateral visual cortical network and lateral occipital and cuneal cortex, and (b) auditory system network and angular gyrus. In AD, we found decreased network-to-region connectivity between the dorsal visual stream network and lateral occipital and parietal opercular cortex. Region-to-region connectivity was decreased in bvFTD between superior temporal gyrus and cuneal, supracalcarine, intracalcarine cortex, and lingual gyrus. Conclusion: We showed that the pathophysiology

The stroke oxygen pilot study: a randomized control trial of the effects of routine oxygen supplementation early after acute stroke--effect on key outcomes at six months

Introduction: Post-stroke hypoxia is common, and may adversely affect outcome. We have recently shown that oxygen supplementation may improve early neurological recovery. Here, we report the six-month outcomes of this pilot study. Methods: Patients with a clinical diagnosis of acute stroke were randomized within 24 h of admission to oxygen supplementation at 2 or 3 L/min for 72 h or to control treatment (room air). Outcomes (see below) were assessed by postal questionnaire at 6 months. Analysis was by intention-to-treat, and statistical significance was set at p#0.05. Results: Out of 301 patients randomized two refused/withdrew consent and 289 (148 in the oxygen and 141 in the control group) were included in the analysis: males 44%, 51%; mean (SD) age 73 (12), 71 (12); median (IQR) National Institutes of Health Stroke Scale score 6 (3, 10), 5 (3, 10) for the two groups respectively. At six months 22 (15%) patients in the oxygen group and 20 (14%) in the control group had died; mean survival in both groups was 162 days (p= 0.99). Median (IQR) scores for the primary outcome, the modified Rankin Scale, were 3 (1, 5) and 3 (1, 4) for the oxygen and control groups respectively. The covariate-adjusted odds ratio was 1.04 (95% CI 0.67, 1.60), indicating that the odds of a lower (i.e. better) score were non-significantly higher in the oxygen group (p= 0.86). The mean differences in the ability to perform basic (Barthel Index) and extended activities of daily living (NEADL), and quality of life (EuroQol) were also non-significant. Conclusions: None of the key outcomes differed at 6 months between the groups. Although not statistically significant and generally of small magnitude, the effects were predominantly in favour of the oxygen group; a larger trial, powered to show differences in longer-term functional outcomes, is now on-going. Trial Registration: Controlled-Trials.com ISRCTN12362720; Eudract.ema.europa.eu 2004-001866-4

Chance of aneurysm in patients suspected of SAH who have a ‘negative’ CT scan but a ‘positive’ lumbar puncture

In patients with sudden severe headache and a negative computed tomography (CT) scan, a lumbar puncture (LP) is performed to rule in or out a subarachnoid haemorrhage (SAH), but this procedure is under debate. In a hospital-based series of 30 patients with sudden headache, a negative CT scan but a positive LP (defined as detection of bilirubin >0.05 at wavelength 458 nm), we studied the chance of harbouring an aneurysm and the clinical outcome. Aneurysms were found in none of both patients who presented within 3 days, in 8 of the 18 (44%) who presented within 4–7 days and in 5 of the 10 (50%) who presented within 8–14 days. Of the 13 patients with an aneurysm, 3 (23%) had poor outcome. In patients who present late after sudden headache, the yield in terms of aneurysms is high in those who have a positive lumbar puncture. In patients with an aneurysm as cause of the positive lumbar puncture, outcome is in the same range as in SAH patients admitted in good clinical condition

[18F]Flortaucipir PET Across Various MAPT Mutations in Presymptomatic and Symptomatic Carriers

OBJECTIVE: To assess the [18F]flortaucipir binding distribution across MAPT mutations in presymptomatic and symptomatic carriers. METHODS: We compared regional [18F]flortaucipir binding potential(BPND) derived from a 130-minute dynamic [18F]flortaucipir PET scan, in nine (pre)symptomatic MAPT mutation carriers(4 with P301L[1 symptomatic], 2 with R406W[1 symptomatic]; 1 presymptomatic L315R, 1 presymptomatic S320F and 1 symptomatic G272V carrier) with 30 cognitively normal controls and 52 Alzheimer's disease patients. RESULTS: [18F]flortaucipir BPND images showed overall highest binding in the symptomatic carriers. This was most pronounced in the symptomatic R406W carrier in whom tau binding exceeded the normal control range in the anterior cingulate cortex, insula, amygdala, temporal, parietal and frontal lobe. Elevated medial temporal lobe BPND was observed in a presymptomatic R406W carrier. The single symptomatic and one of the three presymptomatic P301L carriers showed elevated [18F]flortaucipir BPND in the insula, parietal and frontal lobe compared to controls. The symptomatic G272V carrier exhibited a widespread elevated cortical BPND, with at neuropathological examination a combination of 3R pathology and encephalitis. The L315R presymptomatic mutation carrier showed higher frontal BPND compared to controls. The BPND values of the S320F presymptomatic mutation carrier fell within the range of controls. CONCLUSION: Presymptomatic MAPT mutation carriers already showed subtle elevated tau binding, whereas symptomatic MAPT mutation carriers showed a more marked increase in [18F]flortaucipir BPND. Tau deposition was most pronounced in R406W MAPT (pre)symptomatic mutation carriers, which is associated with both 3R and 4R tau accumulation. Thus, [18F]flortaucipir may serve as an early biomarker for MAPT mutation carriers in mutations that cause 3R/4R tauopathies

The Dutch Parelsnoer Institute - Neurodegenerative diseases; methods, design and baseline results

Background: The is a collaboration between 8 Dutch University Medical Centers in which clinical data and biomaterials from patients suffering from chronic diseases (so called "Pearls") are collected according to harmonized protocols. The Pearl Neurodegenerative Diseases focuses on the role of biomarkers in the early diagnosis, differential diagnosis and in monitoring the course of neurodegenerative diseases, in particular Alzheimer's disease. Methods: The Pearl Neurodegenerative Diseases is a 3-year follow-up study of patients referred to a memory clinic with cognitive complaints. At baseline, all patients are subjected to a standardized examination, including clinical data and biobank materials, e.g. blood samples, MRI and cerebrospinal fluid. At present, in total more than 1000 patients have been included, of which cerebrospinal fluid and DNA samples are available of 211 and 661 patients, respectively. First descriptives of a subsample of the data (n = 665) shows that patients are diagnosed with dementia (45%), mild cognitive impairment (31%), and subjective memory complaints (24%). Discussion: The Pearl Neurodegenerative Diseases is an ongoing large network collecting clinical data and biomaterials of more than 1000 patients with cognitive impairments. The project has started with data analyses of the baseline characteristics and biomarkers, which will be the starting point of future specific research questions that can be answered by this unique dataset