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Metabolites Mar 2024Multi-omics approaches, which integrate genomics, transcriptomics, proteomics, and metabolomics, have emerged as powerful tools in the diagnosis of rare diseases. We...
Multi-omics approaches, which integrate genomics, transcriptomics, proteomics, and metabolomics, have emerged as powerful tools in the diagnosis of rare diseases. We used untargeted metabolomics and whole-genome sequencing (WGS) to gain a more comprehensive understanding of a rare disease with a complex presentation affecting female twins from a consanguineous family. The sisters presented with polymicrogyria, a Dandy-Walker malformation, respiratory distress, and multiorgan dysfunctions. Through WGS, we identified two rare homozygous variants in both subjects, a pathogenic variant in (p.Arg565Trp) and a novel variant in (p.Glu910Val). These genes have been previously associated with autosomal recessive polymicrogyria and hypomyelinating neuropathy with/without contractures, respectively. The twins exhibited symptoms that overlapped with both of these conditions. The results of the untargeted metabolomics analysis revealed significant metabolic perturbations relating to neurodevelopmental abnormalities, kidney dysfunction, and microbiome. The significant metabolites belong to essential pathways such as lipids and amino acid metabolism. The identification of variants in two genes, combined with the support of metabolic perturbation, demonstrates the rarity and complexity of this phenotype and provides valuable insights into its underlying mechanisms.
PubMed: 38535312
DOI: 10.3390/metabo14030152 -
Computerized Medical Imaging and... Jun 2024Polymicrogyria (PMG) is a disorder of cortical organization mainly seen in children, which can be associated with seizures, developmental delay and motor weakness. PMG...
Polymicrogyria (PMG) is a disorder of cortical organization mainly seen in children, which can be associated with seizures, developmental delay and motor weakness. PMG is typically diagnosed on magnetic resonance imaging (MRI) but some cases can be challenging to detect even for experienced radiologists. In this study, we create an open pediatric MRI dataset (PPMR) containing both PMG and control cases from the Children's Hospital of Eastern Ontario (CHEO), Ottawa, Canada. The differences between PMG and control MRIs are subtle and the true distribution of the features of the disease is unknown. This makes automatic detection of potential PMG cases in MRI difficult. To enable the automatic detection of potential PMG cases, we propose an anomaly detection method based on a novel center-based deep contrastive metric learning loss function (cDCM). Despite working with a small and imbalanced dataset our method achieves 88.07% recall at 71.86% precision. This will facilitate a computer-aided tool for radiologists to select potential PMG MRIs. To the best of our knowledge, our research is the first to apply machine learning techniques to identify PMG solely from MRI. Our code is available at: https://github.com/RichardChangCA/Deep-Contrastive-Metric-Learning-Method-to-Detect-Polymicrogyria-in-Pediatric-Brain-MRI. Our pediatric MRI dataset is available at: https://www.kaggle.com/datasets/lingfengzhang/pediatric-polymicrogyria-mri-dataset.
Topics: Child; Humans; Polymicrogyria; Brain; Magnetic Resonance Imaging; Canada
PubMed: 38522222
DOI: 10.1016/j.compmedimag.2024.102373 -
Georgian Medical News Jan 2024Pediatric neuroimaging presents a unique set of challenges, primarily stemming from the intricacies of normal myelination processes occurring within the initial two...
Pediatric neuroimaging presents a unique set of challenges, primarily stemming from the intricacies of normal myelination processes occurring within the initial two years of life. This complexity is particularly pronounced in the context of pediatric epilepsy, where a substantial proportion of neuroimaging cases appears normal, especially in instances of idiopathic or provoked seizures. Nevertheless, abnormalities in neuroimaging tend to manifest in cases of acute or remote symptomatic seizures. Notably, the etiological landscape of seizures in children diverges significantly from that observed in adults, with neurodevelopmental, neurometabolic, and neuro-infectious factors emerging as predominant contributors. This multicentric study, conducted between November 2021 and November 2023, spanned diverse hospitals across various states in India. Encompassing children from birth to 12 years of age experiencing acute and remote symptomatic seizures, the study meticulously documented clinical and demographic profiles. Exclusion criteria were applied, excluding typical febrile seizures and idiopathic epilepsy syndromes to ensure a focused analysis. The study encompassed a total of 109 cases, revealing a spectrum of neuroimaging findings. Noteworthy among these were cortical malformations, including focal cortical dysplasia (12 cases), tuberous sclerosis (6 cases), polymicrogyria (3 cases), hemimegalencephaly (1 case), lissencephaly (1 case), schizencephaly (2 cases), heterotopias (3 cases), cavernous hemangioma (1 case), and AV malformation (1 case). Additionally, neoplastic lesions (6 cases), neurocysticercosis (5 cases), tuberculoma (4 cases), hippocampal sclerosis (3 cases), post-hypoxic and cerebrovascular accident gliosis (3 cases), leukodystrophies (2 cases), and non-lesional cases (58 cases) were documented. Pediatric neuroimaging in symptomatic seizures may present with normal findings, influenced by interpreter bias and the non-uniform availability of 3T MRI across different medical centers. The diverse causative factors for symptomatic seizures underscore the impact of demographic features, including the endemicity of specific infections and birth injuries, on the observed variability across medical centers. These findings underscore the imperative for a comprehensive understanding and standardization in pediatric neuroimaging practices.
Topics: Child; Child, Preschool; Humans; Infant; Infant, Newborn; Epilepsy; India; Magnetic Resonance Imaging; Neuroimaging; Stroke
PubMed: 38501627
DOI: No ID Found -
Orphanet Journal of Rare Diseases Mar 2024Pallister-Killian syndrome (PKS) is a rare genetic disorder caused by mosaic tetrasomy of 12p with wide neurological involvement. Intellectual disability, developmental... (Review)
Review
BACKGROUND
Pallister-Killian syndrome (PKS) is a rare genetic disorder caused by mosaic tetrasomy of 12p with wide neurological involvement. Intellectual disability, developmental delay, behavioral problems, epilepsy, sleep disturbances, and brain malformations have been described in most individuals, with a broad phenotypic spectrum. This observational study, conducted through brain MRI scan analysis on a cohort of patients with genetically confirmed PKS, aims to systematically investigate the neuroradiological features of this syndrome and identify the possible existence of a typical pattern. Moreover, a literature review differentiating the different types of neuroimaging data was conducted for comparison with our population.
RESULTS
Thirty-one individuals were enrolled (17 females/14 males; age range 0.1-17.5 years old at first MRI). An experienced pediatric neuroradiologist reviewed brain MRIs, blindly to clinical data. Brain abnormalities were observed in all but one individual (compared to the 34% frequency found in the literature review). Corpus callosum abnormalities were found in 20/30 (67%) patients: 6 had callosal hypoplasia; 8 had global hypoplasia with hypoplastic splenium; 4 had only hypoplastic splenium; and 2 had a thin corpus callosum. Cerebral hypoplasia/atrophy was found in 23/31 (74%) and ventriculomegaly in 20/31 (65%). Other frequent features were the enlargement of the cisterna magna in 15/30 (50%) and polymicrogyria in 14/29 (48%). Conversely, the frequency of the latter was found to be 4% from the literature review. Notably, in our population, polymicrogyria was in the perisylvian area in all 14 cases, and it was bilateral in 10/14.
CONCLUSIONS
Brain abnormalities are very common in PKS and occur much more frequently than previously reported. Bilateral perisylvian polymicrogyria was a main aspect of our population. Our findings provide an additional tool for early diagnosis.Further studies to investigate the possible correlations with both genotype and phenotype may help to define the etiopathogenesis of the neurologic phenotype of this syndrome.
Topics: Male; Female; Humans; Child; Infant; Child, Preschool; Adolescent; Polymicrogyria; Chromosome Disorders; Neuroimaging; Brain; Brain Diseases; Chromosomes, Human, Pair 12; Observational Studies as Topic
PubMed: 38459574
DOI: 10.1186/s13023-024-03065-5 -
Diagnostic utility of exome sequencing followed by research reanalysis in human brain malformations.Brain Communications 2024This study aimed to determine the diagnostic yield of singleton exome sequencing and subsequent research-based trio exome analysis in children with a spectrum of brain...
This study aimed to determine the diagnostic yield of singleton exome sequencing and subsequent research-based trio exome analysis in children with a spectrum of brain malformations seen commonly in clinical practice. We recruited children ≤ 18 years old with a brain malformation diagnosed by magnetic resonance imaging and consistent with an established list of known genetic causes. Patients were ascertained nationally from eight tertiary paediatric centres as part of the Australian Genomics Brain Malformation Flagship. Chromosome microarray was required for all children, and those with pathogenic copy number changes were excluded. Cytomegalovirus polymerase chain reaction on neonatal blood spots was performed on all children with polymicrogyria with positive patients excluded. Singleton exome sequencing was performed through a diagnostic laboratory and analysed using a clinical exome sequencing pipeline. Undiagnosed patients were followed up in a research setting, including reanalysis of the singleton exome data and subsequent trio exome sequencing. A total of 102 children were recruited. Ten malformation subtypes were identified with the commonest being polymicrogyria (36%), pontocerebellar hypoplasia (14%), periventricular nodular heterotopia (11%), tubulinopathy (10%), lissencephaly (10%) and cortical dysplasia (9%). The overall diagnostic yield for the clinical singleton exome sequencing was 36%, which increased to 43% after research follow-up. The main source of increased diagnostic yield was the reanalysis of the singleton exome data to include newly discovered gene-disease associations. One additional diagnosis was made by trio exome sequencing. The highest phenotype-based diagnostic yields were for cobblestone malformation, tubulinopathy and lissencephaly and the lowest for cortical dysplasia and polymicrogyria. Pathogenic variants were identified in 32 genes, with variants in 6/32 genes occurring in more than one patient. The most frequent genetic diagnosis was pathogenic variants in . This study shows that over 40% of patients with common brain malformations have a genetic aetiology identified by exome sequencing. Periodic reanalysis of exome data to include newly identified genes was of greater value in increasing diagnostic yield than the expansion to trio exome. This study highlights the genetic and phenotypic heterogeneity of brain malformations, the importance of a multidisciplinary approach to diagnosis and the large number of patients that remain without a genetic diagnosis despite clinical exome sequencing and research reanalysis.
PubMed: 38444904
DOI: 10.1093/braincomms/fcae056 -
BMJ Case Reports Feb 2024The coexistence of an arteriovenous fistula (AVF) and neuronal migration abnormalities is a rare phenomenon. The underlying pathophysiology responsible for these...
The coexistence of an arteriovenous fistula (AVF) and neuronal migration abnormalities is a rare phenomenon. The underlying pathophysiology responsible for these anomalies remains elusive. Neuronal architectural irregularities arise from complex neuronal formation, migration and organisation dysfunctions. Isolated cases of these associations are rarely described in the literature. Here, we present an unusual case involving the coexistence of a pial AVF and a pachygyria-polymicrogyria complex in an early childhood boy. We have provided a detailed description of the neuroimaging characteristics and the therapeutic embolisation in this case, along with follow-up. Additionally, we conduct a comprehensive review of potential hypotheses about the association, referencing prior case reports. The presence of an aberrant blood supply or deviant venous drainage from the developing cortex may contribute to a variety of neuronal migration anomalies.
Topics: Male; Humans; Child, Preschool; Intracranial Arteriovenous Malformations; Polymicrogyria; Embolization, Therapeutic; Arteriovenous Fistula
PubMed: 38423569
DOI: 10.1136/bcr-2023-258820 -
Developmental Medicine and Child... Feb 2024Malformations of cortical development (MCDs) represent a heterogeneous spectrum of disorders characterized by atypical development of the cerebral cortex. MCDs are most... (Review)
Review
Malformations of cortical development (MCDs) represent a heterogeneous spectrum of disorders characterized by atypical development of the cerebral cortex. MCDs are most often diagnosed on the basis of imaging, although subtle lesions, such as focal cortical dysplasia, may only be revealed on neuropathology. Different subtypes have been defined, including lissencephaly, heterotopia, cobblestone malformation, polymicrogyria, and dysgyria. Many MCDs are of genetic origin, although acquired factors, such as congenital cytomegalovirus infections and twinning sequence, can lead to similar phenotypes. In this narrative review, we provide an overview of the diagnostic approach to MCDs, which is illustrated with clinical vignettes, on diagnostic pitfalls such as somatic mosaicism and consanguinity, and recognizable phenotypes on imaging, such as tubulinopathies, the lissencephaly spectrum, tuberous sclerosis complex, and FLNA-related periventricular nodular heterotopia.
PubMed: 38394064
DOI: 10.1111/dmcn.15882 -
Developmental Medicine and Child... Jul 2024Hydrocephalus is rarely described in Joubert-Boltshauser syndrome (JBTS). The aim of this study was to investigate whether this association is a chance occurrence or...
Hydrocephalus is rarely described in Joubert-Boltshauser syndrome (JBTS). The aim of this study was to investigate whether this association is a chance occurrence or potentially signifies a new phenotypic subtype. The databases of Wolfson Medical Center, Sourasky Medical Center, and EB's personal collection were reviewed. Records from an additional family were obtained from RG. The patients' medical records, prenatal ultrasounds, and magnetic resonance imaging were assessed. In addition, we reviewed the medical literature for the association of ventriculomegaly/hydrocephalus (VM/HC) in JBTS. Only seven cases (from five families) were found with prenatal onset of VM/HC, diagnosed during the second trimester; three pregnancies were terminated, one was stillborn and three were born, of which one died within a week, and another died at the age of 6 years. Additional central nervous system findings included dysgenesis of the corpus callosum, delayed sulcation, polymicrogyria, and pachygyria. We found 16 publications describing 54 patients with JBTS and VM/HC: only five were diagnosed at birth and three were diagnosed prenatally. Hydrocephalus is extremely rare in JBTS. The recurrence of this association, reported in several publications in multiple family members, suggests that it might represent a new phenotypic subtype of JBTS possibly associated with specific genes or variants. Further genetic studies are needed to confirm this hypothesis. WHAT THIS PAPER ADDS: The association of fetal hydrocephalus with Joubert-Boltshauser syndrome (JBTS) is very rare but not a chance association. This association represents a new phenotypic subtype of JBTS possibly linked to specific genes or variants.
Topics: Humans; Hydrocephalus; Cerebellum; Eye Abnormalities; Abnormalities, Multiple; Female; Kidney Diseases, Cystic; Male; Retina; Cerebellar Vermis; Magnetic Resonance Imaging; Phenotype; Cerebellar Diseases; Child; Infant, Newborn
PubMed: 38247023
DOI: 10.1111/dmcn.15845 -
Child's Nervous System : ChNS :... May 2024Pathogenic variants in RAC3 cause a neurodevelopmental disorder with brain malformations and craniofacial dysmorphism, called NEDBAF. This gene encodes a small GTPase,...
Pathogenic variants in RAC3 cause a neurodevelopmental disorder with brain malformations and craniofacial dysmorphism, called NEDBAF. This gene encodes a small GTPase, which plays a critical role in neurogenesis and neuronal migration. We report a 31 weeks of gestation fetus with triventricular dilatation, and temporal and perisylvian polymicrogyria, without cerebellar, brainstem, or callosal anomalies. Trio whole exome sequencing identified a RAC3 (NM_005052.3, GRCh38) probably pathogenic de novo variant c.276 T>A p.(Asn92Lys). Eighteen patients harboring 13 different and essentially de novo missense RAC3 variants were previously reported. All the patients presented with corpus callosum malformations. Gyration disorders, ventriculomegaly (VM), and brainstem and cerebellar malformations have frequently been described. The only previous prenatal case associated with RAC3 variant presented with complex brain malformations, mainly consisting of midline and posterior fossa anomalies. We report the second prenatal case of NEDBAF presenting an undescribed pattern of cerebral anomalies, including VM and polymicrogyria, without callosal, cerebellar, or brainstem malformations. All neuroimaging data were reviewed to clarify the spectrum of cerebral malformations.
Topics: Pregnancy; Female; Humans; Polymicrogyria; Prenatal Diagnosis; Nervous System Malformations; Agenesis of Corpus Callosum; Mutation, Missense; Hydrocephalus; rac GTP-Binding Proteins
PubMed: 38214746
DOI: 10.1007/s00381-024-06285-z -
Case Report: Novel biallelic moderately damaging variants in in a patient with cerebellar dysplasia.Frontiers in Pediatrics 2023Rotatin, encoded by the gene, is a centrosomal protein with multiple, emerging functions, including left-right specification, ciliogenesis, and neuronal migration....
Rotatin, encoded by the gene, is a centrosomal protein with multiple, emerging functions, including left-right specification, ciliogenesis, and neuronal migration. Recessive variants in are associated with a neurodevelopmental disorder with microcephaly and malformations of cortical development known as "Microcephaly, short stature, and polymicrogyria with seizures" (MSSP, MIM #614833). Affected individuals show a wide spectrum of clinical manifestations like intellectual disability, poor/absent speech, short stature, microcephaly, and congenital malformations. Here, we report a subject showing a distinctive neuroradiological phenotype and harboring novel biallelic variants in : the c.5500A>G, p.(Asn1834Asp), (dbSNP: rs200169343, ClinVar ID:1438510) and c.19A>G, p.(Ile7Val), (dbSNP: rs201165599, ClinVar ID:1905275) variants. In particular brain magnetic resonance imaging (MRI) showed a peculiar pattern, with cerebellar hypo-dysplasia, and multiple arachnoid cysts in the lateral cerebello-medullary cisterns, in addition to left Meckel cave. Thus, we compare his phenotypic features with current literature, speculating a possible role of newly identified variants in his clinical picture, and supporting a relevant variability in this emerging condition.
PubMed: 38178912
DOI: 10.3389/fped.2023.1326552