Type Of Encephalopathy Research Articles

Early infantile epileptic encephalopathy type 54: clinical and neurophysiological aspects

A clinical case of a boy aged 20 months old with early infantile epileptic encephalopathy (EIEE) type 54 due to mutated HNRNPU gene presumably suffering from genetic generalized epilepsy and impaired psychomotor development is described. Exome-wide sequencing was carried out by using NextSeq 500 (Illumina, USA). Video electroencephalographic (VEEG) monitoring was conducted by using NeuroScope NS425 (Biola, Russia). The patient was noted to suffer from neonatal delayed motor development and muscular hypotonia with atypical petit mal epilepsy with regional onset at the occipital-parietal-posterior temporal areas based on VEEG data developed at age of eight months as well as progressive psychoemotional disorders. Ethosuximide and valproic acid administered together were efficient in alleviating EIEE seizures that requires to be further followed up. The data obtained allow to identify a precise etiology of epilepsy and apply a differential approach to administer anti-epileptic agents.

Whole exome sequencing identified a novel homozygous ARV1 mutation in an Iranian family with developmental and epileptic encephalopathy-38

Developmental and epileptic encephalopathy-38 (DEE38) is an inherited neurodegenerative disorder described by the onset of various type of seizures usually between around 4 and 7 months of age. Mutations in the ARV1 gene have recently been described in association with DEE38. Extracted genomic DNA from blood sample was used to perform whole exome sequencing in an affected member of an Iranian family with Developmental and Epileptic Encephalopathy type 38. The mutational screening revealed a novel homozygote ARV1 gene mutation c.593_594delTT (p.Ile198MetfsTer4) in the proband. We identified a novel homozygous deletion in the ARV1 that associates with the Developmental and epileptic encephalopathy-38.

Role of microRNAs As Biomarkers in Sepsis-Associated Encephalopathy.

Sepsis-associated encephalopathy (SAE) is a neurological complication of sepsis, characterized by brain dysfunction without any direct central nervous system infection. The diagnosis of SAE is currently a challenge. In fact, problems in making a diagnosis of SAE cause a great variability of incidence that can reach up to 70% of all septic patients. Even more, despite SAE is the most frequent type of encephalopathy occurring in critically ill patients, the molecular mechanisms that guide its progression have not been completely elucidated. On the other hand, miRNAs have proven to be excellent biomarkers for both diagnosis and prognosis, especially in brain pathologies because of their small size they can cross the blood–brain barrier easier than other biomolecules. The identification of new miRNAs as biomarkers may help to improve SAE diagnosis and prognosis and also to design new therapies for this clinical manifestation that produces diffuse cerebral dysfunction. This review is focused on SAE physiopathology and the need to have clear criteria for its diagnosis; thus, this work postulates some miRNA candidates to be used for SAE biomarkers because of their role in both, neurological damage and sepsis.

Triphasic Waves Are Generated by Widespread Bilateral Cortical Networks.

Triphasic waves (TWs) have been observed in the EEG recorded in patients with various types of encephalopathy, yet their genesis and significance is still debated. The aim of this study was to elucidate the localization of the cortical generators of TWs using EEG source imaging. In 20 consecutive patients who had encephalopathy with TWs, EEG source imaging of the first negative and the positive phases of the TW was performed. Three different approaches were used: equivalent current dipoles, a distributed source model, and a recently described spatial filtration method for visualizing EEG in source space. Equivalent current dipole models failed to provide valid solutions. The distributed source model and the spatial filtration method suggested that TWs were generated by large, bilateral cortical networks, invariably involving the anterior frontal and the temporo-polar areas. Source imaging localized TWs to anterior frontal and temporo-frontal structures. Involvement of these regions is consistent with the typical pathophysiological changes of altered consciousness and cognitive changes observed in patients with TW encephalopathy.

The G127V variant of the prion protein interferes with dimer formation in vitro but not in cellulo

Scrapie prion, PrPSc, formation is the central event of all types of transmissible spongiform encephalopathies (TSEs), while the pathway with possible intermediates and their mechanism of formation from the normal isoform of prion (PrP), remains not fully understood. Recently, the G127V variant of the human PrP is reported to render the protein refractory to transmission of TSEs, via a yet unknown mechanism. Molecular dynamics studies suggested that this mutation interferes with the formation of PrP dimers. Here we analyze the dimerization of 127G and 127VPrP, in both in vitro and a mammalian cell culture system. Our results show that while molecular dynamics may capture the features affecting dimerization in vitro, G127V inhibiting dimer formation of PrP, these are not evidenced in a more complex cellular system.

RHOBTB2 Mutations Expand the Phenotypic Spectrum of Alternating Hemiplegia of Childhood

To explore the phenotypic spectrum of RHOBTB2-related disorders and specifically to determine whether patients fulfill criteria for alternating hemiplegia of childhood (AHC), we report the clinical features of 11 affected individuals. Individuals with RHOBTB2-related disorders were identified through a movement disorder clinic at a specialist pediatric center, with additional cases identified through collaboration with other centers internationally. Clinical data were acquired through retrospective case-note review. Eleven affected patients were identified. All had heterozygous missense variants involving exon 9 of RHOBTB2, confirmed as de novo in 9 cases. All had a complex motor phenotype, including at least 2 different kinds of movement disorder, e.g., ataxia and dystonia. Many patients demonstrated several features fulfilling the criteria for AHC: 10 patients had a movement disorder including paroxysmal elements, and 8 experienced hemiplegic episodes. In contrast to classic AHC, commonly caused by mutations in ATP1A3, these events were reported later only in RHOBTB2 mutation-positive patients from 20 months of age. Seven patients had epilepsy, but of these, 4 patients achieved seizure freedom. All patients had intellectual disability, usually moderate to severe. Other features include episodes of marked skin color change and gastrointestinal symptoms, each in 4 patients. Although heterozygous RHOBTB2 mutations were originally described in early infantile epileptic encephalopathy type 64, our study confirms that they account for a more expansive clinical phenotype, including a complex polymorphic movement disorder with paroxysmal elements resembling AHC. RHOBTB2 testing should therefore be considered in patients with an AHC-like phenotype, particularly those negative for ATPA1A3 mutations.

A case of early infantile epileptic encephalopathy type 7 with partial response to pyridoxal Phosphate

A case of early infantile epileptic encephalopathy type 7 with partial response to pyridoxal Phosphate

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Clinical Genetic Characteristics of Epilepsy Due to Mutations in the PCDH19 Gene (OMIM: 300088)

Objectives: to analyze the clinical genetic characteristics of PCDH19-associated epilepsy in a cohort of patients from the population of the Russian Federation. Materials and methods. The cohort of patients with early epileptic encephalopathy consisted of 16 patients aged from 10 months to 30 years. All patients underwent neurological examination by standard methods, exome sequencing, and electroencephalogram monitoring. Results. Most of the mutations detected were frameshift mutations or mutations forming a stop codon. Six were duplications and four were deletions of a single nucleotide, while three were nonsense mutations. Polymorphism in the clinical manifestations of convulsions were found, which were independent of the type of mutation and its location, which is consistent with results reported by other authors. Conclusions. This study of the clinical genetic features of our patients leads to the conclusion that the PCDH19 gene has so-called hot spots, which are mutated more frequently than other parts of the gene, and that the clinical picture of epileptic encephalopathy type 9, induced by mutations in the PCDH19 gene, is variable.

Variant-specific changes in persistent or resurgent sodium current in SCN8A-related epilepsy patient-derived neurons.

Missense variants in the SCN8A voltage-gated sodium channel gene are linked to early-infantile epileptic encephalopathy type 13, also known as SCN8A-related epilepsy. These patients exhibit a wide spectrum of intractable seizure types, severe developmental delay, movement disorders, and elevated risk of sudden unexpected death in epilepsy. The mechanisms by which SCN8A variants lead to epilepsy are poorly understood, although heterologous expression systems and mouse models have demonstrated altered sodium current properties. To investigate these mechanisms using a patient-specific model, we generated induced pluripotent stem cells from three patients with missense variants in SCN8A: p.R1872>L (Patient 1); p.V1592>L (Patient 2); and p.N1759>S (Patient 3). Using small molecule differentiation into excitatory neurons, induced pluripotent stem cell-derived neurons from all three patients displayed altered sodium currents. Patients 1 and 2 had elevated persistent current, while Patient 3 had increased resurgent current compared to controls. Neurons from all three patients displayed shorter axon initial segment lengths compared to controls. Further analyses focused on one of the patients with increased persistent sodium current (Patient 1) and the patient with increased resurgent current (Patient 3). Excitatory cortical neurons from both patients had prolonged action potential repolarization. Using doxycycline-inducible expression of the neuronal transcription factors neurogenin 1 and 2 to synchronize differentiation of induced excitatory cortical-like neurons, we investigated network activity and response to pharmacotherapies. Both small molecule differentiated and induced patient neurons displayed similar abnormalities in action potential repolarization. Patient induced neurons showed increased burstiness that was sensitive to phenytoin, currently a standard treatment for SCN8A-related epilepsy patients, or riluzole, an FDA-approved drug used in amyotrophic lateral sclerosis and known to block persistent and resurgent sodium currents, at pharmacologically relevant concentrations. Patch-clamp recordings showed that riluzole suppressed spontaneous firing and increased the action potential firing threshold of patient-derived neurons to more depolarized potentials. Two of the patients in this study were prescribed riluzole off-label. Patient 1 had a 50% reduction in seizure frequency. Patient 3 experienced an immediate and dramatic seizure reduction with months of seizure freedom. An additional patient with a SCN8A variant in domain IV of Nav1.6 (p.V1757>I) had a dramatic reduction in seizure frequency for several months after starting riluzole treatment, but then seizures recurred. Our results indicate that patient-specific neurons are useful for modelling SCN8A-related epilepsy and demonstrate SCN8A variant-specific mechanisms. Moreover, these findings suggest that patient-specific neuronal disease modelling offers a useful platform for discovering precision epilepsy therapies.

New mutations in KCNT2 gene causing early infantile epileptic encephalopathy type 57: Case study and literature review

Early infantile epileptic encephalopathy (EIEE) 57 belongs to a group of encephalopathies with early-onset and characterised by severe electroencephalogram abnormalities, seizures, developmental delay and intellectual disability. We carried out Whole Exome analysis using Next Generation Sequencing (NGS) and bioinformatic analysis performed to find mutation associated with the patient phenotypes. The effect of the mutation on protein structure analysed by PolyPhen2 and Swissmodel ExPASy. In this study, we evaluated two unrelated Turkish males diagnosed with EIEE type 57 to investigate the genetic cause of this disease. Whole exome sequencing revealed mutations in KCN2 gene, which is a member of Potassium channels (KCN) gene family associated with epileptic encephalopathies. Two mutations, c.545A>T (p.Asn182Ile and c.2638C>A (p.Leu880Met) were reported here as a novel mutation. Our findings implicate the genotype-phenotype correlation of these mutations. Furthermore, the computational analysis showed their effect on protein binding site and function suggesting their role in the development of early infantile epileptic encephalopathy 57.

Neurological Complications of COVID-19 and Possible Neuroinvasion Pathways: A Systematic Review.

The Coronavirus Disease 2019 (COVID-19) outbreak has shocked the whole world with its unexpected rapid spread. The virus responsible for the disease, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), enters host cells by means of the envelope spike protein, which binds to angiotensin-converting enzyme 2 receptors. These receptors are highly expressed in heart, lungs, respiratory tract epithelium, endothelial cells and brain. Since an increasing body of significant evidence is highlighting a possible neuroinvasion related to SARS-CoV-2, a state of the art on the neurological complications is needed. To identify suitable publications, our systematic review was carried out by searching relevant studies on PubMed and Scopus databases. We included studies investigating neurologic manifestations of SARS-CoV-2 in patients over 18. According to the analyzed studies, the most frequent disorders affecting central nervous system (CNS) seem to be the following: olfactory and taste disorders, ischemic/hemorrhagic stroke, meningoencephalitis and encephalopathy, including acute necrotizing encephalopathy, a rare type of encephalopathy. As regards the peripheral nervous system (PNS), Guillain-Barré and Miller Fisher syndromes are the most frequent manifestations reported in the literature. Important clinical information on the neurological manifestations of SARS-CoV-2 would help clinicians raise awareness and simultaneously improve the prognosis of critically ill patients.

Sepsis-Associated Brain Dysfunction: A Review of Current Literature.

Sepsis-associated brain dysfunction (SABD) may be the most common type of encephalopathy in critically ill patients. SABD develops in up to 70% of septic patients and represents the most frequent organ insufficiency associated with sepsis. It presents with a plethora of acute neurological features and may have several serious long-term psychiatric consequences. SABD might cause various pathological changes in the brain through numerous mechanisms. Clinical neurological examination is the basic screening method for SABD, although it may be challenging in subjects receiving with opioids and sedative agents. As electrographic seizures and periodic discharges might be present in 20% of septic patients, screening with electroencephalography (EEG) might be useful. Several imaging techniques have been suggested for non-invasive assessment of structure and function of the brain in SABD patients; however, their usefulness is rather limited. Although several experimental therapies have been postulated, at the moment, no specific treatment exists. Clinicians should focus on preventive measures and optimal management of sepsis. This review discusses epidemiology, clinical presentation, pathology, pathophysiology, diagnosis, management, and prevention of SABD.

Cerebrovascular disease in patients with COVID-19: neuroimaging, histological and clinical description.

Since the appearance of the first case of coronavirus disease 2019 (COVID-19) a pandemic has emerged affecting millions of people worldwide. Although the main clinical manifestations are respiratory, an increase in neurological conditions, specifically acute cerebrovascular disease, has been detected. We present cerebrovascular disease case incidence in hospitalized patients with SARS-CoV-2 infection. Patients were confirmed by microbiological/serological testing, or on chest CT semiology. Available data on comorbidity, laboratory parameters, treatment administered, neuroimaging, neuropathological studies and clinical evolution during hospitalization, measured by the modified Rankin scale, were analysed. A bivariate study was also designed to identify differences between ischaemic and haemorrhagic subtypes. A statistical model of binary logistic regression and sensitivity analysis was designed to study the influence of independent variables over prognosis. In our centre, there were 1683 admissions of patients with COVID-19 over 50 days, of which 23 (1.4%) developed cerebrovascular disease. Within this group of patients, cerebral and chest CT scans were performed in all cases, and MRI in six (26.1%). Histological samples were obtained in 6/23 cases (two brain biopsies, and four arterial thrombi). Seventeen patients were classified as cerebral ischaemia (73.9%, with two arterial dissections), five as intracerebral haemorrhage (21.7%), and one leukoencephalopathy of posterior reversible encephalopathy type. Haemorrhagic patients had higher ferritin levels at the time of stroke (1554.3 versus 519.2, P = 0.004). Ischaemic strokes were unexpectedly frequent in the vertebrobasilar territory (6/17, 35.3%). In the haemorrhagic group, a characteristic radiological pattern was identified showing subarachnoid haemorrhage, parieto-occipital leukoencephalopathy, microbleeds and single or multiple focal haematomas. Brain biopsies performed showed signs of thrombotic microangiopathy and endothelial injury, with no evidence of vasculitis or necrotizing encephalitis. The functional prognosis during the hospital period was unfavourable in 73.9% (17/23 modified Rankin scale 4–6), and age was the main predictive variable (odds ratio = 1.5; 95% confidence interval 1.012–2.225; P = 0.043). Our series shows cerebrovascular disease incidence of 1.4% in patients with COVID-19 with high morbidity and mortality. We describe pathological and radiological data consistent with thrombotic microangiopathy caused by endotheliopathy with a haemorrhagic predisposition.

Atypical Type of Hypertensive Encephalopathy: A Novel Case

Atypical Type of Hypertensive Encephalopathy: A Novel Case

Multi-parametric magnetic resonance imaging in acute necrotizing encephalopathy of children: validity and prognostic value

BackgroundAcute necrotizing encephalopathy of children (ANEC) is a rare fulminant type of acute encephalopathy that mainly occurs in children with a characteristic clinico-radiological pattern. It is commonly preceded by viral infections. The condition carries a poor prognosis with high morbidity and mortality rates. We highlight the relationship between diagnostic multi-parametric magnetic resonance imaging (MRI) findings and correlate them with the clinical outcome of children with ANEC by enrollment of MRI scoring.ResultsThe thalami were involved in all 30 patients, brain stem in 80%, basal ganglia (13.3%), cerebral white matter (WM) in 73%, and cerebellar WM in 33%. Hemorrhage was present in 86.7% patients, edema 80%, and necrosis in 13.3%. We found that the patients having the highest MRI scores were in the poor outcome category; whereas the patients with lower MR score (1 or 2) had better outcomes. Statistically positive correlation (r= 0.1198) was found between the multi-parametric MR score and the outcome category.ConclusionAn extended multi-parametric MRI should be performed in ANEC, allowing early detection and scoring of the disease for better prognosis. There is a positive correlation between the clinical outcome and the MR scoring.

Early Infantile Epileptic Encephalopathy Type 14: Three Cases of Infantile Epilepsy with Migrating Focal Seizures Due to Mutations in the KCNT1 Gene

Objectives. To study the clinical and electroencephalographic characteristics of early infantile epileptic encephalopathy (EIEE) type 14, due to mutations in the KCNT1 gene. Materials and methods. Over the period 2017–2019, three unrelated girls (M.V. aged three years three months, T.V. aged nine months, and M.U. aged five months) with the clinical picture of infantile epilepsy with migrating focal seizures (IEMFS) were investigated and mutations in the KCNT1 gene were identified. New-generation DNA sequencing (Inherited Epilepsy panel) was run on an Illumina NextSeq 500 platform (USA). Video EEG monitoring was with an Encephalan Video system based on an Encephalan-RM RM-EEG-19/26 instrument (Medikom MTD, Russia). Results and conclusions. M.V. showed a previously undescribed mutation in exon 12 of the KCNT1 gene (chr9:138656907C>T) with amino acid substitution Arg356Trp. T.V. had a known mutation in chromosome 9, 138651532G>A with amino acid substitution of glycine by serine as position 288, i.e., Gly288Ser (OMIM: 608167.0010). M.U. showed a previously undescribed heterozygous mutation in exon 15 of the KCTN1 gene (chr9:138660712A>G), leading to an amino acid substitution in position 480 (Asp480Gly). In M.V., the onset of EIEE was at age four months with hypomotor dialeptic and tonic versive seizures. Epilepsy in T.V. started at age 4.5 months with hypomotor seizures with ophthalmoclonia and facial hyperemia. In M.V., neonatal convulsions were seen with bilateral tonic-clinic seizures and cyanosis, and subsequent development of status epilepticus with alternating hemiconvulsions. All girls went on to develop seizures of multiregional genesis to the level of migrating status epilepticus with the typical electroclinical picture of IEMFS. Thus, these findings lead to the conclusion that the KCNT1 gene may be the main gene determining the development of EIEE.

Diseases Caused by Mutations in Mitochondrial Carrier Genes SLC25: A Review.

In the 1980s, after the mitochondrial DNA (mtDNA) had been sequenced, several diseases resulting from mtDNA mutations emerged. Later, numerous disorders caused by mutations in the nuclear genes encoding mitochondrial proteins were found. A group of these diseases are due to defects of mitochondrial carriers, a family of proteins named solute carrier family 25 (SLC25), that transport a variety of solutes such as the reagents of ATP synthase (ATP, ADP, and phosphate), tricarboxylic acid cycle intermediates, cofactors, amino acids, and carnitine esters of fatty acids. The disease-causing mutations disclosed in mitochondrial carriers range from point mutations, which are often localized in the substrate translocation pore of the carrier, to large deletions and insertions. The biochemical consequences of deficient transport are the compartmentalized accumulation of the substrates and dysfunctional mitochondrial and cellular metabolism, which frequently develop into various forms of myopathy, encephalopathy, or neuropathy. Examples of diseases, due to mitochondrial carrier mutations are: combined D-2- and L-2-hydroxyglutaric aciduria, carnitine-acylcarnitine carrier deficiency, hyperornithinemia-hyperammonemia-homocitrillinuria (HHH) syndrome, early infantile epileptic encephalopathy type 3, Amish microcephaly, aspartate/glutamate isoform 1 deficiency, congenital sideroblastic anemia, Fontaine progeroid syndrome, and citrullinemia type II. Here, we review all the mitochondrial carrier-related diseases known until now, focusing on the connections between the molecular basis, altered metabolism, and phenotypes of these inherited disorders.

Fulminant encephalopathy in a child with hyperferritinemic sepsis: a case report

BackgroundSepsis-associated encephalopathy (SAE) is epidemic in intensive care units and recognized as a fatal complication of sepsis. SAE is characterized by diffuse brain dysfunction and the correct diagnosis of SAE requires ruling out direct central nervous system (CNS) infection or other types of encephalopathy, such as hepatic encephalopathy, pulmonary encephalopathy, and other encephalopathy.Case presentationWe reported a rare case of a 5-year-old girl who presented with abdominal pain, vomiting, recurrent seizures, and coma. Brain magnetic resonance imaging (MRI) showed diffuse white matter abnormalities in the brain on day 1. Cerebrospinal fluid (CSF) tests revealed that protein levels and glucose levels were normal without pleocytosis. CSF PCRs for pathogens were all negative. The electroencephalography examination demonstrated diffuse, generalized and slow background activity. The patient showed the symptom of hyperferritinemic sepsis with multiple organ dysfunction syndrome (MODS). SAE was also diagnosed by ruling out other encephalitis or encephalopathy. The patient made marked improvements of clinical symptoms and the lesions on brain imaging disappeared completely within two months after appropriate treatment including antibiotic treatments, methylprednisolone, intravenous immunoglobulin, membrane-based therapeutic plasma exchange (TPE), and continuous renal replacement therapy (CRRT).ConclusionsSAE can be a fatal complication of sepsis which asks for immediate diagnosis and treatment. Few reports have focus on MRI imaging findings on the early onset of hyperferritinemic sepsis with MODS since these children were too ill to undergo an MRI scan. However, SAE might appear before other systemic features of sepsis are obvious, and MRI could show abnormal lesion in the brain during the early course. Therefore, MRI should be performed early to diagnose this fatal complication which would play important roles in improving the clinical outcomes by early initiation with appropriate treatments.

Early infantile epileptic encephalopathy type 16: the new clinical and genetic variant of TBC1D24 gene mutation

Objective: to analyse the clinical and neurophysiological data from a case of early infantile epileptic encephalopathy type 16 in a child with homozygous mutation in TBC1D24 gene. Material and methods . Female child M. aged 1 year and 2 months, with identified mutations in TBC1D24 gene was examined. The whole exome sequencing was performed (Next Generation Sequencing with the Illumina HiSeq 1500 platform, USA). Dynamic video-EEG monitoring was conducted with a “Encephalan-Video” RM-19/26 instrument (“Medicom MTD”, Russia). Results . According to the patient history, on the 22nd day of life, the child developed vocalisms with tonic tension of the limbs. At her 2 months of life, focal myoclonia and myoclono-clonies were noted; at her 4 months – return of tonic seizures with vocalisms followed by eyelid myoclonus, perioral myoclonus, ophthalmoclonia, alternating hemiconvulsions and tonic-clonic seizures. The family history of epilepsy was negative; the parents denied any consanguinity, but admitted a chance of being distant relatives. Neurological examination revealed hypotonic-astatic syndrome and psycho-motor retardation. A video EEG monitoring test detected multiple EEG negative multifocal myoclonic episodes in combination with dystonic hyperkinesia and motor automatism. Although typical epileptiform spike-wave discharges were rare, a focus of low-index spike-wave complexes was identified in the left temporal zone. Therapy with valproates, barbiturates and levetiracetam did not produce any significant effect but benzodiazepines (clonazepam) caused a moderate improvement; a switch to clobazam therapy was then recommended. This case of inherited developmental and epileptic encephalopathy was defined as early infantile epileptic encephalopathy type 16 (OMIM#615338) with autosomal recessive inheritance associated with a previously not described homozygous mutation of the TBC1D24 gene, chr:16:2546775 A>C that caused Tyr209Ser amino acid substitution. Pre-conception testing of the TBC1D24 gene under the IVF condition is recommended to the parents. Discussion . Since 2010, a few variants of early infantile epileptic encephalopathy type 16 caused by homozygous mutation of the TBC1D24 gene have been described in the literature. This clinical case is closer to progressive myoclonic epilepsy with dystonia (PMED), which indicates the nosological autonomy of this form of epilepsy. С onclusion . Children with pharmacoresistant epilepsy and epileptic encephalopathies, as well as those with unusual course of these diseases need genetic assessment with the new generation exom sequencing techniques – such as the “hereditary epilepsy” panel, as well as clinical and full-exom sequencing. All authors contributed equally to this publication.