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ANKRD11 (ankyrin repeat domain 11) is a chromatin regulator and the only gene associated with KBG syndrome, a rare neurodevelopmental disorder. We have previously shown that Ankrd11 regulates murine embryonic cortical neurogenesis. Here, we show a novel olfactory bulb phenotype in a KBG syndrome mouse model and two diagnosed patients. Conditional knockout of Ankrd11 in murine embryonic neural stem cells leads to aberrant postnatal olfactory bulb development and reduced size due to reduction of the olfactory bulb granule cell layer. We further show that the rostral migratory stream has incomplete migration of neuroblasts, reduced cell proliferation as well as aberrant differentiation of neurons. This leads to reduced neuroblasts and neurons in the olfactory bulb granule cell layer. In vitro, Ankrd11-deficient neural stem cells from the postnatal subventricular zone display reduced migration, proliferation, and neurogenesis. Finally, we describe two clinically and molecularly confirmed KBG syndrome patients with anosmia and olfactory bulb and groove hypo-dysgenesis/agenesis. Our report provides evidence that Ankrd11 is a novel regulator of olfactory bulb development and neuroblast migration. Moreover, our study highlights a novel clinical sign of KBG syndrome linked to ANKRD11 perturbations in mice and humans.
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Anormalidades Múltiplas , Doenças do Desenvolvimento Ósseo , Deficiência Intelectual , Anormalidades Dentárias , Humanos , Animais , Camundongos , Fácies , Bulbo Olfatório , Modelos Animais de DoençasRESUMO
INTRODUCTION: Acute alterated mental status (AAMS) is often a challenge for clinicians, since the underlying etiologies cannot always easily be inferred based on the patient's clinical presentation, medical history or early examinations. The aim of this study is to evaluate the role of the electroencephalogram (EEG) as a diagnostic tool in AAMS of unknown etiology in children. MATERIALS AND METHODS: We conducted a prospective study involving EEG assessments on children presenting with AAMS between May 2017 and October 2019. Inclusion criteria were age 1 month to 18 years and acute (<1 week) and persistent (>5 minutes) Altered mental status (AMS). Patients with a known etiology of AAMS were excluded. A literature review was also performed. RESULTS: Twenty patients (median age: 7.7 years, range: 0.5-15.4) were enrolled. EEG contributed to the diagnosis in 14/20 cases, and was classified as diagnostic in 9/20 and informative in 5/20. Specifically, EEG was able to identify nonconvulsive status epilepticus (NCSE) in 5 children and psychogenic events in 4. EEG proved to be a poorly informative diagnostic tool at AAMS onset in 6 children, however in 5 of them, it proved useful during follow-up. CONCLUSIONS: Limited data exist regarding the role of EEG in children with AAMS of unknown etiology. In our population EEG proved to be valuable tool, and was especially useful in the prompt identification of NCSE and psychogenic events.
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OBJECTIVE: To evaluate the relationship between impaired brain growth and structural brain abnormalities at term-equivalent age (TEA) and neurodevelopment in extremely low-birth-weight (ELBW) infants over the first 2 years. METHODS: ELBW infants born from 2009 through 2018 and undergoing brain magnetic resonance imaging (MRI) at TEA were enrolled in this retrospective cohort study. MRI scans were reviewed using a validated quali-quantitative score, including several white and gray matter items. Neurodevelopment was assessed at 6, 12, 18, and 24 months using the Griffiths scales. The independent associations between MRI subscores and the trajectories of general and specific neurodevelopmental functions were analyzed by generalized estimating equations. RESULTS: One hundred-nine ELBW infants were included. White matter volume reduction and delayed myelination were associated with worse general development (b = -2.33, P = .040; b = -6.88, P = .049 respectively), social skills (b = -3.13, P = .019; b = -4.79, P = .049), and eye-hand coordination (b = -3.48, P = .009; b = -7.21, P = .045). Cystic white matter lesions were associated with poorer motor outcomes (b = -4.99, P = .027), while white matter signal abnormalities and corpus callosum thinning were associated with worse nonverbal cognitive performances (b = -6.42, P = .010; b = -6.72, P = .021, respectively). Deep gray matter volume reduction correlated with worse developmental trajectories. CONCLUSIONS: Distinctive MRI abnormalities correlate with specific later developmental skills. This finding may suggest that TEA brain MRI may assist with neurodevelopmental prediction, counseling of families, and development of targeted supportive interventions to improve neurodevelopment in ELBW neonates.
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Encefalopatias , Recém-Nascido Prematuro , Recém-Nascido , Lactente , Humanos , Pré-Escolar , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia , Recém-Nascido de Peso Extremamente Baixo ao NascerRESUMO
BACKGROUND: Preschool age (i.e. children under six years of age) represents a red flag for requiring neuroimaging to exclude secondary potentially urgent intracranial conditions (PUIC) in patients with acute headache. We investigated the clinical characteristics of preschoolers with headache to identify the features associated with a greater risk of secondary "dangerous" headache. METHODS: We performed a multicenter exploratory retrospective study in Italy from January 2017 to December 2018. Preschoolers with new-onset non-traumatic headache admitted to emergency department were included and were subsequently divided into two groups: hospitalized and discharged. Among hospitalized patients, we investigated the characteristics linked to potentially urgent intracranial conditions. RESULTS: We included 1455 preschoolers with acute headache. Vomiting, ocular motility disorders, ataxia, presence of neurological symptoms and signs, torticollis and nocturnal awakening were significantly associated to hospitalization. Among the 95 hospitalized patients, 34 (2.3%) had potentially urgent intracranial conditions and more frequently they had neurological symptoms and signs, papilledema, ataxia, cranial nerves paralysis, nocturnal awakening and vomiting. Nevertheless, on multivariable logistic regression analysis, we found that only ataxia and vomiting were associated with potentially urgent intracranial conditions. CONCLUSION: Our study identified clinical features that should be carefully evaluated in the emergency department in order to obtain a prompt diagnosis and treatment of potentially urgent intracranial conditions. The prevalence of potentially urgent intracranial conditions was low in the emergency department, which may suggest that age under six should not be considered an important risk factor for malignant causes as previously thought.
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Serviço Hospitalar de Emergência , Cefaleia , Pré-Escolar , Humanos , Criança , Estudos Retrospectivos , Cefaleia/etiologia , Vômito/epidemiologia , Vômito/complicações , Ataxia/complicaçõesRESUMO
Somatic symptom disorders (SSDs) are a group of clinical conditions characterized by heterogeneous physical symptoms, not directly supported by a demonstrable organic process. Despite representing a growing problem in the pediatric age, the literature lacks studies assessing the psychopathological and clinical features of subjects with SSD, particularly during the SARS-CoV-2 pandemic. This is a retrospective, observational study, involving two historical cohorts of children admitted to a tertiary referral Italian hospital over the 2 years preceding and following the start of the SARS-CoV-2 pandemic. Demographic, clinical, socio-economical, and psychological variables were investigated. Standardized tests for the developmental age were administered to assess psychopathological variables. Overall rates and trends of accesses for SSD, as compared to the total accesses for any cause at the Pediatric Emergency Room during the same periods, were reported as well. Fifty-one (pre-pandemic, 29; pandemic, 22) children with SSD were enrolled (age, 11.4 ± 2.4 years, F = 66.7%). Subjects in the pandemic historical cohort reported more frequently fever (p < 0.001), headache (p = 0.032), and asthenia (p < 0.001), as well as more chronic conditions in personal and family history, and fewer previous hospital accesses, as compared to the pre-pandemic cohort. Depressed mood and anxious traits were documented in both samples. None of them had an ongoing or a previously reported SARS-CoV-2 infection. During the pandemic, a clinical psychologist was more frequently consulted before the hospital discharge to mental health services, to support the diagnosis. Conclusion: This study showed the significant burden of SSD in children, highlighting the need to implement pediatricians' education to optimize the management of these patients. Children with SSD who accessed during the SARS-CoV-2 pandemic presented specific clinical features. Future studies, conducted on longitudinal and controlled samples, are indicated to further investigate children with these conditions. What is Known: ⢠Somatic symptoms disorders (SSDs) are frequent in the pediatric age, especially in early adolescence. ⢠Evidence remains scarce on the impact of the SARS-CoV-2 pandemic on SSDs in children. What is New: ⢠Children with SSD who accessed during the SARS-CoV-2 pandemic presented specific clinical features. ⢠The implementation of pediatricians' education and a multidisciplinary approach are needed to optimize the management of SSDs.
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COVID-19 , Sintomas Inexplicáveis , Transtornos Mentais , Adolescente , Humanos , Criança , SARS-CoV-2 , COVID-19/epidemiologia , Pandemias , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Serviço Hospitalar de EmergênciaRESUMO
AIM: We describe the association of neurofibromatosis type 1 (NF1) and feeding and eating disorders (FED) in five patients admitted to our third level centre for both FED and NF1. METHODS: Case series of five adolescent females with NF1 treated for FED. RESULTS: We collected data from five patients with NF1 aged between 14 and 22 years, all females. The onset of eating disorder symptoms occurred between 13 and 19 years of age and was characterised by food intake restriction, associated with physical hyperactivity in three out of five cases. One patient also reported self-injurious acts and episodic binges. Patients received diagnoses of anorexia nervosa (AN, n = 2), atypical AN (n = 1), bulimia nervosa (n = 1), unspecified feeding and eating disorder (n = 1). CONCLUSION: The current literature reports a single case of an adult with NF1 and comorbid AN, focusing on the dermatological features of NF1. Our article describes a case series of five patients in developmental age affected by NF1 and FED. Clinical and psychological features of NF1 may play a role in the pathogenesis of FED when these two conditions co-occur. The dermatological alterations of NF1 may contribute to body image distortion that characterises AN. Further research is required to systematically screen populations of patients with NF1 for the presence of FED.
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Anorexia Nervosa , Bulimia Nervosa , Transtornos da Alimentação e da Ingestão de Alimentos , Neurofibromatose 1 , Adolescente , Feminino , Humanos , Adulto Jovem , Anorexia Nervosa/complicações , Anorexia Nervosa/diagnóstico , Anorexia Nervosa/psicologia , Imagem Corporal , Bulimia Nervosa/diagnóstico , Bulimia Nervosa/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnósticoRESUMO
Bi-allelic alterations in the MDH2 gene have recently been reported in three unrelated toddlers with early-onset severe encephalopathy. Here, we describe a new case of a child carrying novel variants in MDH2. This child presented with early-onset encephalocardiopathy requiring heart transplant and showed cerebellar ataxia and drug-responsive epilepsy; his family history was significant for multiple cancers, a feature often associated with monoallelic variants in MDH2. Functional studies in cultured skin fibroblasts from the proband showed reduced protein levels and impaired enzyme activity, further corroborating the genetic results. The relatively mild neurological presentation and severe cardiac manifestations requiring heart transplant distinguish this case from previous reports. This patient thus expands the spectrum of clinical features associated with MDH2 variants.
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Alelos , Estudos de Associação Genética , Predisposição Genética para Doença , Malato Desidrogenase/genética , Mutação , Fenótipo , Criança , Pré-Escolar , Análise Mutacional de DNA , Genoma Mitocondrial , Humanos , Lactente , Imageamento por Ressonância Magnética , Neuroimagem , Sequenciamento do ExomaRESUMO
BACKGROUND: Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a low-grade tumor characterized by diffuse leptomeningeal infiltrates. Symptoms are usually secondary to hydrocephalus. Hemiplegic migraine (HM)-like episodes have never been associated with DLGNT, but they have been reported with different inflammatory and tumoral entities involving leptomeninges. OBSERVATIONS: We report the case of a 10-year-old boy with recurrent episodes of right hyposthenia, aphasia, and headache lasting hours to days with complete remission. The electroencephalogram during the attack showed diffuse slower activity on the left hemisphere, which improved together with the symptoms. DLGNT was discovered during a follow-up magnetic resonance imaging and confirmed by biopsy. CONCLUSIONS: This is the first report of HM-like attacks in DLGNT. We discuss the pathogenetic hypotheses of our case and previously reported cases of "symptomatic" HM with leptomeningeal involvement.
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Neoplasias do Sistema Nervoso Central , Neoplasias Meníngeas , Transtornos de Enxaqueca , Neoplasias Neuroepiteliomatosas , Neoplasias do Sistema Nervoso Central/patologia , Criança , Hemiplegia/etiologia , Humanos , Masculino , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/patologiaRESUMO
OBJECTIVES: Drug resistant epilepsy has rarely been reported following posterior reversible encephalopathy syndrome (PRES), with few cases of mesial temporal sclerosis (MTS). The aim of this study was to report clinical and neuroimaging features of MTS subsequent to PRES in hemato-oncologic/stem cell transplanted children. MATERIALS AND METHODS: Among 70 children treated in 2 pediatric hemato-oncologic Italian centers between 1994 and 2018 and presenting an episode of PRES, we retrospectively identified and analyzed a subgroup of patients who developed epilepsy and MTS. RESULTS: Nine of 70 patients (12.8%) developed post-PRES persistent seizures with magnetic resonance imaging evidence of MTS. One patient died few months after MTS diagnosis, because of hematologic complications; the remaining 8 patients showed unprovoked seizures over time leading to the diagnosis of epilepsy, focal in all and drug resistant in 4. At PRES diagnosis, all patients with further evidence of epilepsy and MTS suffered of convulsive seizures, evolving into status epilepticus in 3. In 3 patients a borderline cognitive level or intellectual disability were diagnosed after the onset of epilepsy, and 2 had behavioral problems impacting their quality of life. CONCLUSIONS: MTS and long-term focal epilepsy, along with potential cognitive and behavioral disorders, are not uncommon in older pediatric patients following PRES.
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Eletroencefalografia , Epilepsia , Neoplasias Hematológicas , Imageamento por Ressonância Magnética , Síndrome da Leucoencefalopatia Posterior , Convulsões , Adolescente , Criança , Pré-Escolar , Epilepsia/diagnóstico por imagem , Epilepsia/epidemiologia , Epilepsia/fisiopatologia , Feminino , Neoplasias Hematológicas/diagnóstico por imagem , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/terapia , Humanos , Masculino , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/epidemiologia , Síndrome da Leucoencefalopatia Posterior/fisiopatologia , Estudos Retrospectivos , Esclerose , Convulsões/diagnóstico por imagem , Convulsões/epidemiologia , Convulsões/fisiopatologiaRESUMO
TORCH (Toxoplasmosis, Rubella, Cytomegalovirus, Herpes Simplex Virus and Syphilis) infections are a major cause of intrauterine and perinatal infections with associated morbidity and mortality. Neonatal Herpes Simplex Virus infection caused by an enveloped, double-stranded DNA virus of the Herpesviridae family is devastating and fatal. Herpes Viruses are not hepatotropic but may rarely cause hepatitis. Most cases of HSV hepatitis rapidly progress to fulminant hepatic failure and often fatal before the diagnosis or transplantation. Nowadays, despite the availability of antiviral treatment (acyclovir), the outcome remains poor because of late identification of hepatic Herpes Simplex Virus (HSV) infection. We report a male neonate suspected with a metabolic/mitochondrial disease and multi-organ involvement but who developed a fulminant hepatic failure and disseminated coagulopathy secondary to HSV type 1 (HSV-1) infection. The postmortem diagnosis was performed demonstrating HSV-1 in liver tissue by transmission electron microscopy and by retrospective detection of HSV specific antigens by immunohistochemistry.
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Herpes Simples , Herpesvirus Humano 1 , Falência Hepática Aguda , Necrose Hepática Massiva , Feminino , Herpes Simples/complicações , Herpes Simples/diagnóstico , Herpes Simples/tratamento farmacológico , Humanos , Recém-Nascido , Falência Hepática Aguda/diagnóstico , Falência Hepática Aguda/etiologia , Masculino , Necrose Hepática Massiva/complicações , Gravidez , Complicações Infecciosas na Gravidez , Estudos RetrospectivosRESUMO
Biallelic mutations in SNORD118, encoding the small nucleolar RNA U8, cause leukoencephalopathy with calcifications and cysts (LCC). Given the difficulty in interpreting the functional consequences of variants in nonprotein encoding genes, and the high allelic polymorphism across SNORD118 in controls, we set out to provide a description of the molecular pathology and clinical spectrum observed in a cohort of patients with LCC. We identified 64 affected individuals from 56 families. Age at presentation varied from 3 weeks to 67 years, with disease onset after age 40 years in eight patients. Ten patients had died. We recorded 44 distinct, likely pathogenic, variants in SNORD118. Fifty two of 56 probands were compound heterozygotes, with parental consanguinity reported in only three families. Forty nine of 56 probands were either heterozygous (46) or homozygous (three) for a mutation involving one of seven nucleotides that facilitate a novel intramolecular interaction between the 5' end and 3' extension of precursor-U8. There was no obvious genotype-phenotype correlation to explain the marked variability in age at onset. Complementing recently published functional analyses in a zebrafish model, these data suggest that LCC most often occurs due to combinatorial severe and milder mutations, with the latter mostly affecting 3' end processing of precursor-U8.
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Calcinose/genética , Estudos de Associação Genética , Leucoencefalopatias/genética , RNA Nucleolar Pequeno/genética , Adolescente , Adulto , Idoso , Animais , Calcinose/complicações , Calcinose/patologia , Criança , Pré-Escolar , Consanguinidade , Modelos Animais de Doenças , Feminino , Heterozigoto , Humanos , Lactente , Recém-Nascido , Leucoencefalopatias/complicações , Leucoencefalopatias/patologia , Masculino , Pessoa de Meia-Idade , Patologia Molecular , Adulto Jovem , Peixe-Zebra/genéticaRESUMO
PURPOSE: The aim of this study was to characterize clinically, etiologically, and electroencephalographically focal Nonconvulsive Status Epilepticus (NCSE) in children. Moreover, we tried to identify focal NCSE features distinguishing between different ages, NCSE etiologies, and cases of de novo onset. METHODS: We retrospectively identified patients (aged 1 month to 18 years) who had EEG-documented focal NCSE between January 2001 and December 2019. We analyzed the clinical features, etiology, and EEG features of each event. RESULTS: Thirty-eight patients were included in this study. NCSE had a de novo onset in 26 patients and was the first manifestation of previously undiagnosed epilepsy in 12 patients. NCSE etiology was acute symptomatic in 13 patients. Acute symptomatic NCSE events were mainly observed in hospitalized children, were usually longer, and had a significantly higher frequency of repetitive EEG patterns than other etiologies. In patients with epilepsy, the etiology of NCSE was remote symptomatic in 14, progressive in 6, and cryptogenic in 5; a definite or suspected genetic disorder was observed in 11. EEG localization was frequent in posterior regions (18 children). Eleven patients had refractory NCSE and 4 required admission to the intensive care unit. CONCLUSION: Focal NCSE in children is more frequent in the first years of life, mainly involves posterior regions, and often has de novo onset. In the case of de novo focal NCSE both acute symptomatic NCSE and new-onset epilepsy must be considered and investigated. A higher frequency of repetitive EEG patterns and an inpatient setting are significantly associated with acute symptomatic NCSE.
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Epilepsia , Estado Epiléptico , Criança , Eletroencefalografia , Humanos , Unidades de Terapia Intensiva , Estudos Retrospectivos , Estado Epiléptico/diagnóstico , Estado Epiléptico/epidemiologia , Estado Epiléptico/etiologiaRESUMO
BACKGROUND: Epilepsy is a main feature of Mowat Wilson Syndrome (MWS), a congenital malformation syndrome caused by ZEB2 variants. The aim of this study was to investigate the long-term evolution of the electroclinical phenotype of MWS in a large population. METHODS: Forty-individuals with a genetically confirmed diagnosis were enrolled. Three age groups were identified (t1â¯=â¯0-4; t2â¯=â¯5-12; t3â¯=â¯>13â¯years); clinical data and EEG records were collected, analyzed, and compared for age group. Video-EEG recorded seizures were reviewed. RESULTS: Thirty-six of 40 individuals had epilepsy, of whom 35/35 aged >5â¯years. Almost all (35/36) presented focal seizures at onset (mean age at onset 3.4⯱â¯2.3 SD) that persisted, reduced in frequency, in 7/22 individuals after the age of 13. Absences occurred in 22/36 (mean age at onset 7.2⯱â¯0.9 SD); no one had absences before 6 and over 16â¯years old. Paroxysmal interictal abnormalities in sleep also followed an age-dependent evolution with a significant increase in frequency at school age (pâ¯=â¯0.002) and a reduction during adolescence (pâ¯=â¯0.008). Electrical Status Epilepticus during Sleep occurred in 14/36 (13/14 aged 5-13â¯years old at onset). Seven focal seizure ictal video-EEGs were collected: all were long-lasting and more visible clinical signs were often preceded by prolonged electrical and/or subtle (erratic head and eye orientation) seizures. Valproic acid was confirmed as the most widely used and effective drug, followed by levetiracetam. CONCLUSIONS: Epilepsy is a major sign of MWS with a characteristic, age-dependent, electroclinical pattern. Improvement with adolescence/adulthood is usually observed. Our data strengthen the hypothesis of a GABAergic transmission imbalance underlying ZEB2-related epilepsy.
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Noradrenaline (NE) is a catecholamine acting as both a neurotransmitter and a hormone, with relevant effects in modulating feeding behavior and satiety. Several studies have assessed the relationship between the noradrenergic system and Eating Disorders (EDs). This systematic review aims to report the existing literature on the role of the noradrenergic system in the development and treatment of EDs. A total of 35 studies were included. Preclinical studies demonstrated an involvement of the noradrenergic pathways in binge-like behaviors. Genetic studies on polymorphisms in genes coding for NE transporters and regulating enzymes have shown conflicting evidence. Clinical studies have reported non-unanimous evidence for the existence of absolute alterations in plasma NE values in patients with Anorexia Nervosa (AN) and Bulimia Nervosa (BN). Pharmacological studies have documented the efficacy of noradrenaline-modulating therapies in the treatment of BN and Binge Eating Disorder (BED). Insufficient evidence was found concerning the noradrenergic-mediated genetics of BED and BN, and psychopharmacological treatments targeting the noradrenergic system in AN. According to these data, further studies are required to expand the existing knowledge on the noradrenergic system as a potential target for treatments of EDs.
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Encéfalo/metabolismo , Transtornos da Alimentação e da Ingestão de Alimentos/tratamento farmacológico , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Norepinefrina/metabolismo , Neurônios Adrenérgicos/efeitos dos fármacos , Neurônios Adrenérgicos/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Comportamento Alimentar/fisiologia , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico por imagem , Humanos , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismoRESUMO
Autozygosity-driven exome analysis has been shown effective for identification of genes underlying recessive diseases especially in countries of the so-called Greater Middle East (GME), where high consanguinity unravels the phenotypic effects of recessive alleles and large family sizes facilitate homozygosity mapping. In Italy, as in most European countries, consanguinity is estimated low. Nonetheless, consanguineous Italian families are not uncommon in publications of genetic findings and are often key to new associations of genes with rare diseases. We collected 52 patients from 47 consanguineous families with suspected recessive diseases, 29 originated in GME countries and 18 of Italian descent. We performed autozygosity-driven exome analysis by detecting long runs of homozygosity (ROHs > 1.5 Mb) and by prioritizing candidate clinical variants within. We identified a pathogenic synonymous variant that had been previously missed in NARS2 and we increased an initial high diagnostic rate (47%) to 55% by matchmaking our candidate genes and including in the analysis shorter ROHs that may also happen to be autozygous. GME and Italian families contributed to diagnostic yield comparably. We found no significant difference either in the extension of the autozygous genome, or in the distribution of candidate clinical variants between GME and Italian families, while we showed that the average autozygous genome was larger and the mean number of candidate clinical variants was significantly higher (p = 0.003) in mutation-positive than in mutation-negative individuals, suggesting that these features influence the likelihood that the disease is autozygosity-related. We highlight the utility of autozygosity-driven genomic analysis also in countries and/or communities, where consanguinity is not widespread cultural tradition.
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Testes Genéticos/métodos , Genoma Humano/genética , Mapeamento Cromossômico/métodos , Consanguinidade , Exoma/genética , Família , Feminino , Genes Recessivos/genética , Humanos , Itália , Masculino , Oriente Médio , Mutação/genética , LinhagemRESUMO
Loss-of-function mutations in the SPART gene cause Troyer syndrome, a recessive form of spastic paraplegia resulting in muscle weakness, short stature, and cognitive defects. SPART encodes for Spartin, a protein linked to endosomal trafficking and mitochondrial membrane potential maintenance. Here, we identified with whole exome sequencing (WES) a novel frameshift mutation in the SPART gene in 2 brothers presenting an uncharacterized developmental delay and short stature. Functional characterization in an SH-SY5Y cell model shows that this mutation is associated with increased neurite outgrowth. These cells also show a marked decrease in mitochondrial complex I (NADH dehydrogenase) activity, coupled to decreased ATP synthesis and defective mitochondrial membrane potential. The cells also presented an increase in reactive oxygen species, extracellular pyruvate, and NADH levels, consistent with impaired complex I activity. In concordance with a severe mitochondrial failure, Spartin loss also led to an altered intracellular Ca2+ homeostasis that was restored after transient expression of wild-type Spartin. Our data provide for the first time a thorough assessment of Spartin loss effects, including impaired complex I activity coupled to increased extracellular pyruvate. In summary, through a WES study we assign a diagnosis of Troyer syndrome to otherwise undiagnosed patients, and by functional characterization we show that the novel mutation in SPART leads to a profound bioenergetic imbalance.-Diquigiovanni, C., Bergamini, C., Diaz, R., Liparulo, I., Bianco, F., Masin, L., Baldassarro, V. A., Rizzardi, N., Tranchina, A., Buscherini, F., Wischmeijer, A., Pippucci, T., Scarano, E., Cordelli, D. M., Fato, R., Seri, M., Paracchini, S., Bonora, E. A novel mutation in SPART gene causes a severe neurodevelopmental delay due to mitochondrial dysfunction with complex I impairments and altered pyruvate metabolism.
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Proteínas de Ciclo Celular/genética , Complexo I de Transporte de Elétrons/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Mutação/genética , Transtornos do Neurodesenvolvimento/genética , Piruvatos/metabolismo , Cálcio/metabolismo , Linhagem Celular , Criança , Complexo I de Transporte de Elétrons/metabolismo , Endossomos/genética , Endossomos/metabolismo , Humanos , Masculino , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , NAD/genética , NAD/metabolismo , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Transtornos do Neurodesenvolvimento/metabolismoRESUMO
BACKGROUND: The combination of febrile illness-induced encephalopathy and rhabdomyolysis has thus far only been described in disorders that affect cellular energy status. In the absence of specific metabolic abnormalities, diagnosis can be challenging. OBJECTIVE: The objective of this study was to identify and characterise pathogenic variants in two individuals from unrelated families, both of whom presented clinically with a similar phenotype that included neurodevelopmental delay, febrile illness-induced encephalopathy and episodes of rhabdomyolysis, followed by developmental arrest, epilepsy and tetraplegia. METHODS: Whole exome sequencing was used to identify pathogenic variants in the two individuals. Biochemical and cell biological analyses were performed on fibroblasts from these individuals and a yeast two-hybrid analysis was used to assess protein-protein interactions. RESULTS: Probands shared a homozygous TRAPPC2L variant (c.109G>T) resulting in a p.Asp37Tyr missense variant. TRAPPC2L is a component of transport protein particle (TRAPP), a group of multisubunit complexes that function in membrane traffic and autophagy. Studies in patient fibroblasts as well as in a yeast system showed that the p.Asp37Tyr protein was present but not functional and resulted in specific membrane trafficking delays. The human missense mutation and the analogous mutation in the yeast homologue Tca17 ablated the interaction between TRAPPC2L and TRAPPC10/Trs130, a component of the TRAPP II complex. Since TRAPP II activates the GTPase RAB11, we examined the activation state of this protein and found increased levels of the active RAB, correlating with changes in its cellular morphology. CONCLUSIONS: Our study implicates a RAB11 pathway in the aetiology of the TRAPPC2L disorder and has implications for other TRAPP-related disorders with similar phenotypes.
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Alelos , Fibroblastos/metabolismo , Mutação , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/genética , Proteínas rab de Ligação ao GTP/genética , Adolescente , Biomarcadores , Biópsia , Pré-Escolar , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Imageamento por Ressonância Magnética , Mutação de Sentido Incorreto , Fenótipo , Transporte Proteico , Sequenciamento do ExomaRESUMO
PURPOSE: Mowat-Wilson syndrome (MWS) is a rare intellectual disability/multiple congenital anomalies syndrome caused by heterozygous mutation of the ZEB2 gene. It is generally underestimated because its rarity and phenotypic variability sometimes make it difficult to recognize. Here, we aimed to better delineate the phenotype, natural history, and genotype-phenotype correlations of MWS. METHODS: In a collaborative study, we analyzed clinical data for 87 patients with molecularly confirmed diagnosis. We described the prevalence of all clinical aspects, including attainment of neurodevelopmental milestones, and compared the data with the various types of underlying ZEB2 pathogenic variations. RESULTS: All anthropometric, somatic, and behavioral features reported here outline a variable but highly consistent phenotype. By presenting the most comprehensive evaluation of MWS to date, we define its clinical evolution occurring with age and derive suggestions for patient management. Furthermore, we observe that its severity correlates with the kind of ZEB2 variation involved, ranging from ZEB2 locus deletions, associated with severe phenotypes, to rare nonmissense intragenic mutations predicted to preserve some ZEB2 protein functionality, accompanying milder clinical presentations. CONCLUSION: Knowledge of the phenotypic spectrum of MWS and its correlation with the genotype will improve its detection rate and the prediction of its features, thus improving patient care.
Assuntos
Doença de Hirschsprung/diagnóstico , Doença de Hirschsprung/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Microcefalia/diagnóstico , Microcefalia/genética , Anormalidades Múltiplas/genética , Adolescente , Adulto , Criança , Pré-Escolar , Fácies , Feminino , Estudos de Associação Genética/métodos , Genótipo , Humanos , Lactente , Masculino , Mutação , Fenótipo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genéticaRESUMO
In the last years, several cases of pediatric epilepsies misdiagnosed and treated as gastrointestinal (GI) disorders have been reported. The aim of this study was to evaluate both frequency and characteristics of these erroneous diagnoses. We identified children who had received a previous misdiagnosis of GI disorder out of 858 consecutive patients with a diagnosis of epilepsy at our hospital from 2010 to 2015. Misdiagnosis was observed in 21 patients (2.4%): 7 children with West syndrome, 10 with temporal lobe epilepsy, and 4 with Panayiotopoulos syndrome. The majority of children with a misdiagnosis (12/21) were younger than 1year at epilepsy onset, and median diagnostic delay was 15.5months. The most frequently diagnosed GI disorder was gastroesophageal reflux disease, especially in younger children. The study confirms that epilepsy in a significant percentage of children is wrongly identified and treated as GI disorders. In particular, epilepsy should be considered in the differential diagnosis of "atypical" gastroesophageal reflux in younger children in order to avoid serious prognostic consequences.