Neuropathology of central nervous system involvement in TTR amyloidosis.

Hereditary transthyretin amyloidosis (ATTRv) is a systemic disease caused by the accumulation of misfolded transthyretin (TTR). It usually presents with an adult-onset progressive axonal peripheral neuropathy and cardiomyopathy. In the central nervous system (CNS), variant TTR is produced by the choroid plexus and accumulates in the leptomeninges.

Intellectual disability genomics: current state, pitfalls and future challenges.

Intellectual disability (ID) can be caused by non-genetic and genetic factors, the latter being responsible for more than 1700 ID-related disorders. The broad ID phenotypic and genetic heterogeneity, as well as the difficulty in the establishment of the inheritance pattern, often result in a delay in the diagnosis. It has become apparent that massive parallel sequencing can overcome these difficulties.

Adult polyglucosan body disease-an atypical compound heterozygous with a novel GBE1 mutation.

Introduction: Adult polyglucosan body disease (APBD) is an autosomal recessive leukodystrophy characterized by neurogenic bladder starting after 40 years old, spastic paraparesis and peripheral neuropathy. It is mainly resultant from the GBE1 homozygous p.Tyr329Ser (c.

Usher syndrome and Nebulin-associated myopathy in a single patient due to variants in and .

In a patient with Usher syndrome and atypical muscle complaints, we have identified two separate variants in and genes by exome sequencing. The homozygous variants in these two recessive genes could explain the full phenotype of our patient.

Two Compound Heterozygous Variants in Cause Stereotypies and Dystonia in Autosomal Recessive Spinocerebellar Ataxia 20.

Autosomal Recessive Spinocerebellar Ataxia 20, SCAR20, is a rare condition characterized by intellectual disability, lack of speech, ataxia, coarse facies and macrocephaly, caused by variants. While all cases described are due to homozygous variants that generally result in loss of protein, so far there are no other cases of reported compound heterozygous variants. Here we describe the first non-consanguineous SCAR20 family, the second Portuguese, with two siblings presenting similar clinical features caused by compound heterozygous variants: NM_001350532.

Clinicopathological correlations of sural nerve biopsies in Val30Met familial amyloid polyneuropathy.

Familial amyloid polyneuropathy with the substitution of methionine for valine at position 30 in the gene is the most common type of hereditary transthyretin amyloidosis. Although several authors have previously reported a size-dependent fibre loss, predominantly involving unmyelinated and small-diameter myelinated fibres, the mechanisms of nerve fibre loss have not been fully understood. In this study, we establish the morphometric pattern of peripheral neuropathy in patients with familial amyloid polyneuropathy and asymptomatic mutation carriers in the biopsies from our archive and correlated the pathological findings with clinical features.

LAMA2 gene mutation update: Toward a more comprehensive picture of the laminin-α2 variome and its related phenotypes.

Congenital muscular dystrophy type 1A (MDC1A) is one of the main subtypes of early-onset muscle disease, caused by disease-associated variants in the laminin-α2 (LAMA2) gene. MDC1A usually presents as a severe neonatal hypotonia and failure to thrive. Muscle weakness compromises normal motor development, leading to the inability to sit unsupported or to walk independently.

The etiology of spontaneous intracerebralhemorrhage: Insights from a neuropathological series.

The etiology of intracerebral hemorrhage (ICH) is frequently undetermined. We aimed to assess the impact of the neuropathological study on the etiologic diagnosis of ICH. Patients with ICH admitted to a tertiary hospital in the last 14 years were identified, and histological samples of surgically-drained ICH were retrieved.

Inflammatory pathology markers (activated microglia and reactive astrocytes) in early and late onset Alzheimer disease: a post mortem study.

Aims: The association between the pathological features of AD and dementia is stronger in younger old persons than in older old persons suggesting that additional factors are involved in the clinical expression of dementia in the oldest old. Cumulative data suggests that neuroinflammation plays a prominent role in Alzheimer's disease (AD) and different studies reported an age-associated dysregulation of the neuroimmune system. Consequently, we sought to characterize the pattern of microglial cell activation and astrogliosis in brain post mortem tissue of pathologically confirmed cases of early and late onset AD (EOAD and LOAD) and determine their relation to age.

Exonization of an Intronic LINE-1 Element Causing Becker Muscular Dystrophy as a Novel Mutational Mechanism in Dystrophin Gene.

A broad mutational spectrum in the dystrophin () gene, from large deletions/duplications to point mutations, causes Duchenne/Becker muscular dystrophy (D/BMD). Comprehensive genotyping is particularly relevant considering the mutation-centered therapies for dystrophinopathies. We report the genetic characterization of a patient with disease onset at age 13 years, elevated creatine kinase levels and reduced dystrophin labeling, where multiplex-ligation probe amplification (MLPA) and genomic sequencing failed to detect pathogenic variants.

Patterns of Microglial Cell Activation in Alzheimer Disease and Frontotemporal Lobar Degeneration.

Aims: Microglia-driven neuroinflammation can play an important role in the pathophysiology of neurodegenerative disorders. In this study, we sought to characterize the distribution of microglial cell activation in 2 neurodegenerative dementias with distinct protein signatures, Alzheimer disease (AD) and frontotemporal lobar degeneration (FTLD) of the TDP subtype, and to determine if there was an anatomical correlation with the phenotypes most commonly associated with these conditions.

Methods: The distribution and extent of microglial cell activation was assessed semiquantitatively in the hippocampal formation, cortical gray matter, and subcortical white matter of CD68-immunostained sections of the frontal, temporal, parietal, and occipital cortices from 15 pathologically confirmed cases of AD, 13 cases of FTLD, and 18 controls.

Amyloid detection in the transverse carpal ligament of patients with hereditary ATTR V30M amyloidosis and carpal tunnel syndrome.

Introduction: Carpal tunnel syndrome (CTS) is a nonspecific manifestation of hereditary ATTR amyloidosis (ATTRm). Amyloid deposition of wild-type TTR (WT-ATTR) has been found in transverse carpal ligament (TCL) in idiopathic CTS. We retrospectively studied a group of patients with ATTRm and CTS submitted to carpal tunnel release surgery (CTRS).

RYR1-Related Myopathies: Clinical, Histopathologic and Genetic Heterogeneity Among 17 Patients from a Portuguese Tertiary Centre.

Background: Pathogenic variants in ryanodine receptor type 1 (RYR1) gene are an important cause of congenital myopathy. The clinical, histopathologic and genetic spectrum is wide.

Objective: Review a group of the patients diagnosed with ryanodinopathy in a tertiary centre from North Portugal, as an attempt to define some phenotypical patterns that may help guiding future diagnosis.

Clinical, biochemical, molecular, and histological features of 65 Portuguese patients with mitochondrial disorders.

Introduction: Mitochondrial disorders display remarkable genetic and phenotypic heterogeneity.

Methods: We performed a retrospective analysis of the clinical, histological, biochemical, and genetic features of 65 patients with molecular diagnoses of mitochondrial disorders.

Results: The most common genetic diagnosis was a single large-scale mitochondrial DNA (mtDNA) deletion (41.

Does the Interplay Between Aging and Neuroinflammation Modulate Alzheimer's Disease Clinical Phenotypes? A Clinico-Pathological Perspective.

Alzheimer's disease (AD) is a chronic neurodegenerative disorder and is the most common cause of dementia worldwide. Cumulative data suggests that neuroinflammation plays a prominent and early role in AD, and there is compelling data from different research groups of age-associated dysregulation of the neuroimmune system. From the clinical point of view, despite clinical resemblance and neuropathological findings, there are important differences between the group of patients with sporadic early-onset (<65 years old) and late-onset AD (>65 years old).

DJ-1 linked parkinsonism (PARK7) is associated with Lewy body pathology.

Mutations in DJ-1 (encoded by PARK7) are a very rare cause of early-onset recessive Parkinson's disease. We describe a patient with early-onset parkinsonism, starting at the age of 22, with poor response to levodopa and additional features in progression (dystonia, pyramidal signs and dementia), who died when he was 49 years old. The neuropathological study showed severe substantia nigra and locus coeruleus neuronal loss, with diffuse Lewy body pathology (Lewy bodies, aberrant neurites, grain-like structures, spheroids and scattered glial pathology).

New massive parallel sequencing approach improves the genetic characterization of congenital myopathies.

Congenital myopathies (CMs) are a heterogeneous group of muscle diseases characterized by hypotonia, delayed motor skills and muscle weakness with onset during the first years of life. The diagnostic workup of CM is highly dependent on the interpretation of the muscle histology, where typical pathognomonic findings are suggestive of a CM but are not necessarily gene specific. Over 20 loci have been linked to these myopathies, including three exceptionally large genes (TTN, NEB and RYR1), which are a challenge for molecular diagnosis.

CADASIL: MRI may be normal in the fourth decade of life - a case report.

Background Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) manifests by migraine with aura, cerebral ischemic events, mood disturbances and dementia. Brain MRI lesions typically precede the symptoms from 10 to 15 years and previous evidence showed all CADASIL patients above 35 years old have an abnormal MRI, supporting the clinical diagnosis. Case results We present a 37-year-old female patient with migraine without aura, a family history of CADASIL, normal brain 3-Tesla MRI and normal skin biopsy, even though a pathogenic NOTCH3 gene mutation (allele 2, exon 11, c.

New splicing mutation in the choline kinase beta (CHKB) gene causing a muscular dystrophy detected by whole-exome sequencing.

Muscular dystrophies (MDs) are a group of hereditary muscle disorders that include two particularly heterogeneous subgroups: limb-girdle MD and congenital MD, linked to 52 different genes (seven common to both subgroups). Massive parallel sequencing technology may avoid the usual stepwise gene-by-gene analysis. We report the whole-exome sequencing (WES) analysis of a patient with childhood-onset progressive MD, also presenting mental retardation and dilated cardiomyopathy.

Ryanodine myopathies without central cores--clinical, histopathologic, and genetic description of three cases.

Background: Mutations in ryanodine receptor 1 gene (RYR1) are frequent causes of myopathies. They classically present with central core disease; however, clinical variability and histopathologic overlap are being increasingly recognized.

Patients: Patient 1 is a 15-year-old girl with mild proximal, four-limb weakness from age 5, presenting with a progressive scoliosis starting at age 10.