Identification and diagnosis of ultra-rapid progressive dementia: evidence from a prospective cohort study and systematic literature review.

Background And Objectives: The term rapid progressive dementia (RPD) may be applied to patients who develop dementia within 1 year or complete incapacitation within 2 years of the first symptom of impairment. However, in select cases, cognitive impairment may emerge abruptly, with symptoms evolving across hours or days. We sought to determine the frequency, etiologies, and factors that associated with ultra-RPD.

Promoting Growth in Behavioral Neurology: A Path Forward.

Behavioral neurology & neuropsychiatry (BNNP) is a field that seeks to understand brain-behavior relationships, including fundamental brain organization principles and the many ways that brain structures and connectivity can be disrupted, leading to abnormalities of behavior, cognition, emotion, perception, and social cognition. In North America, BNNP has existed as an integrated subspecialty through the United Council for Neurologic Subspecialties since 2006. Nonetheless, the number of behavioral neurologists across academic medical centers and community settings is not keeping pace with increasing clinical and research demand.

Skin Biopsy Detection of Phosphorylated α-Synuclein in Patients With Synucleinopathies.

Importance: Finding a reliable diagnostic biomarker for the disorders collectively known as synucleinopathies (Parkinson disease [PD], dementia with Lewy bodies [DLB], multiple system atrophy [MSA], and pure autonomic failure [PAF]) is an urgent unmet need. Immunohistochemical detection of cutaneous phosphorylated α-synuclein may be a sensitive and specific clinical test for the diagnosis of synucleinopathies.

Objective: To evaluate the positivity rate of cutaneous α-synuclein deposition in patients with PD, DLB, MSA, and PAF.

Enlarged perivascular spaces are associated with white matter injury, cognition and inflammation in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

Enlarged perivascular spaces have been previously reported in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, but their significance and pathophysiology remains unclear. We investigated associations of white matter enlarged perivascular spaces with classical imaging measures, cognitive measures and plasma proteins to better understand what enlarged perivascular spaces represent in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and whether radiographic measures of enlarged perivascular spaces would be of value in future therapeutic discovery studies for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy. Twenty-four individuals with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and 24 age- and sex-matched controls were included.

Fatigue Impacts Quality of Life in People with Spinocerebellar Ataxias.

Background: Fatigue is a prevalent and debilitating symptom in neurological disorders, including spinocerebellar ataxias (SCAs). However, the risk factors of fatigue in the SCAs as well as its impact have not been well investigated.

Objectives: To study the prevalence of fatigue in SCAs, the factors contributing to fatigue, and the influence of fatigue on quality of life.

Altered Iron and Microstructure in Huntington's Disease Subcortical Nuclei: Insight From 7T MRI.

Background: Pathophysiological changes of Huntington's disease (HD) can precede symptom onset by decades. Robust imaging biomarkers are needed to monitor HD progression, especially before the clinical onset.

Purpose: To investigate iron dysregulation and microstructure alterations in subcortical regions as HD imaging biomarkers, and to associate such alterations with motor and cognitive impairments.

The Cerebellar Cognitive Affective/Schmahmann Syndrome Scale in Spinocerebellar Ataxias.

The Cerebellar Cognitive Affective/Schmahmann Syndrome (CCAS) manifests as impaired executive control, linguistic processing, visual spatial function, and affect regulation. The CCAS has been described in the spinocerebellar ataxias (SCAs), but its prevalence is unknown. We analyzed results of the CCAS/Schmahmann Scale (CCAS-S), developed to detect and quantify CCAS, in two natural history studies of 309 individuals Symptomatic for SCA1, SCA2, SCA3, SCA6, SCA7, or SCA8, 26 individuals Pre-symptomatic for SCA1 or SCA3, and 37 Controls.

Diminished Neuronal ESCRT-0 Function Exacerbates AMPA Receptor Derangement and Accelerates Prion-Induced Neurodegeneration.

Endolysosomal defects in neurons are central to the pathogenesis of prion and other neurodegenerative disorders. In prion disease, prion oligomers traffic through the multivesicular body (MVB) and are routed for degradation in lysosomes or for release in exosomes, yet how prions impact proteostatic pathways is unclear. We found that prion-affected human and mouse brain showed a marked reduction in Hrs and STAM1 (ESCRT-0), which route ubiquitinated membrane proteins from early endosomes into MVBs.

PRNP expression predicts imaging findings in sporadic Creutzfeldt-Jakob disease.

Objective: We explored the relationship between regional PRNP expression from healthy brain tissue and patterns of increased and decreased diffusion and regional brain atrophy in patients with sporadic Creutzfeldt-Jakob disease (sCJD).

Methods: We used PRNP microarray data from 6 healthy adult brains from Allen Brain Institute and T1-weighted and diffusion-weighted MRIs from 34 patients diagnosed with sCJD and 30 age- and sex-matched healthy controls to construct partial correlation matrices across brain regions for specific measures of interest: PRNP expression, mean diffusivity, volume, cortical thickness, and local gyrification index, a measure of cortical folding.

Results: Regional patterns of PRNP expression in the healthy brain correlated with regional patterns of diffusion signal abnormalities and atrophy in sCJD.

Comparison of quantitative susceptibility mapping methods for iron-sensitive susceptibility imaging at 7T: An evaluation in healthy subjects and patients with Huntington's disease.

Quantitative susceptibility mapping (QSM) is a promising tool for investigating iron dysregulation in neurodegenerative diseases, including Huntington's disease (HD). Many diverse methods have been proposed to generate accurate and robust QSM images. In this study, we evaluated the performance of different dipole inversion algorithms for iron-sensitive susceptibility imaging at 7T on healthy subjects of a large age range and patients with HD.

Autoimmune Encephalitis Misdiagnosis in Adults.

Importance: Autoimmune encephalitis misdiagnosis can lead to harm.

Objective: To determine the diseases misdiagnosed as autoimmune encephalitis and potential reasons for misdiagnosis.

Design, Setting, And Participants: This retrospective multicenter study took place from January 1, 2014, to December 31, 2020, at autoimmune encephalitis subspecialty outpatient clinics including Mayo Clinic (n = 44), University of Oxford (n = 18), University of Texas Southwestern (n = 18), University of California, San Francisco (n = 17), University of Washington in St Louis (n = 6), and University of Utah (n = 4).

Caregiver Experiences Navigating the Diagnostic Journey in a Rapidly Progressing Dementia.

Introduction: People with suspected Alzheimer's disease and related dementias (ADRD) and their families experience a burdensome process while seeking a diagnosis. These challenges are problematic in the most common dementia syndromes, but they can be even more distressing in rarer, atypical syndromes such as rapidly progressive dementias (RPDs), which can be fatal within months from onset. This study is an examination of the diagnostic journey experience from the perspective of caregivers of people who died from the prototypic RPD, sporadic Creutzfeldt-Jakob Disease (sCJD).

The S-Factor, a New Measure of Disease Severity in Spinocerebellar Ataxia: Findings and Implications.

Spinocerebellar ataxias (SCAs) are progressive neurodegenerative disorders, but there is no metric that predicts disease severity over time. We hypothesized that by developing a new metric, the Severity Factor (S-Factor) using immutable disease parameters, it would be possible to capture disease severity independent of clinical rating scales. Extracting data from the CRC-SCA and READISCA natural history studies, we calculated the S-Factor for 438 participants with symptomatic SCA1, SCA2, SCA3, or SCA6, as follows: ((length of CAG repeat expansion - maximum normal repeat length) /maximum normal repeat length) × (current age - age at disease onset) × 10).

Retinal arteriolar parameters as a surrogate marker of intracranial vascular pathology.

Introduction: Development of novel diagnostic tools is a top research priority in vascular dementia. A major obstacle is the lack of a simple, non-invasive method to visualize cerebral arteriolar walls in vivo. Retinal arterioles offer a window into the cerebral circulation.

Default Mode Network quantitative diffusion and resting-state functional magnetic resonance imaging correlates in sporadic Creutzfeldt-Jakob disease.

Grey matter involvement is a well-known feature in sporadic Creutzfeldt-Jakob disease (sCJD), yet precise anatomy-based quantification of reduced diffusivity is still not fully understood. Default Mode Network (DMN) areas have been recently demonstrated as selectively involved in sCJD, and functional connectivity has never been investigated in prion diseases. We analyzed the grey matter involvement using a quantitatively multi-parametric MRI approach.

Diagnostic accuracy of cerebrospinal fluid biomarkers in genetic prion diseases.

Genetic prion diseases are a rare and diverse group of fatal neurodegenerative disorders caused by pathogenic sequence variations in the prion protein gene, PRNP. Data on CSF biomarkers in patients with genetic prion diseases are limited and conflicting results have been reported for unclear reasons. Here, we aimed to analyse the diagnostic accuracy of CSF biomarkers currently used in prion clinical diagnosis in 302 symptomatic genetic prion disease cases from 11 prion diagnostic centres, encompassing a total of 36 different pathogenic sequence variations within the open reading frame of PRNP.

Developing neuropalliative care for sporadic Creutzfeldt-Jakob Disease.

We aimed to identify targets for neuropalliative care interventions in sporadic Creutzfeldt-Jakob disease by examining characteristics of patients and sources of distress and support among former caregivers. We identified caregivers of decedents with sporadic Creutzfeldt-Jakob disease from the University of California San Francisco Rapidly Progressive Dementia research database. We purposively recruited 12 caregivers for in-depth interviews and extracted associated patient data.