Search Results (631)

Mouse models of genetic diseases are important research tools. However, the genetic background of the mouse strain can significantly influence how a genetic mutation is expressed. Studies on preclinical models of phenylketonuria (PKU), an inherited metabolic disorder, have used two strains, BTBR and C57Bl/6, created via a chemically induced point mutation in the gene encoding the enzyme phenylalanine hydroxylase (BTBR^enu2 and C57^enu2, respectively). Despite having the same levels of hyperphenylalaninemia (HPA), published results indicate differences in neural and behavioral phenotypes between the two backgrounds. To explore this difference further, the current study examines the genome-wide transcriptome of the prefrontal cortex (pFC), the brain region which is the most vulnerable to the negative effects of HPA. Regardless of the strain, the enu2 mutation upregulated the expression of several aminoacyl-tRNA synthetases and eukaryotic translation initiation factors, suggesting an essential modification in the protein translation process and supporting the downregulation of gene programs related to myelination. Accordingly, we deepened the exploration of cognitive dysfunctions in C57^enu2− mice, showing a previously unreported working memory impairment under increasing information load. These findings identify convergent pFC molecular and cognitive alterations induced by HPA across distinct genetic backgrounds, providing clinically relevant insights into mechanisms that may contribute to executive dysfunctions in PKU. Full article

Background/Objectives: The first 1000 days of life represent a critical window for growth and neurodevelopment, during which nutrition strongly influences brain development and metabolic programming. In phenylketonuria (PKU), dietary management is essential to prevent neurological impairment and later-life risk of non-communicable diseases (NCDs). This review examines current evidence on PKU from pregnancy through complementary feeding, highlighting the impact of nutritional strategies on neurodevelopmental and metabolic outcomes. Methods: This narrative review, following PRISMA guidelines, used a systematic search of PubMed and Scopus with defined PICO questions. Original research, reviews, and guidelines on PKU nutrition during the first 1000 days were included, emphasizing neurological and metabolic outcomes. Results: Articles addressed prenatal and postnatal factors in PKU. Optimised metabolic control in women with PKU is critical to prevent maternal PKU syndrome, reducing risks of miscarriage, congenital heart defects, microcephaly, and neurocognitive impairment. Pre-conception dietary management, frequent blood Phe monitoring, supplementation with Phe-free protein substitutes (PSs), micronutrients, and emerging pharmacological therapies support maternal and foetal health. Following newborn screening, early dietary treatment in infants with PKU maintains plasma Phe within safe ranges, promoting growth and neurodevelopment. Breastfeeding, combined with Phe-free infant PSs, is feasible, and complementary feeding should be introduced carefully. Frequent monitoring and tailored dietary adjustments, including second-stage PSs, support metabolic control, while data on gut microbiota remain limited. Conclusions: Early multidisciplinary interventions are crucial to optimise metabolic and neurodevelopmental outcomes during this window of opportunity. Further research is needed to address remaining gaps and optimise PKU management across the first 1000 days. Full article

Background/Objectives: Edwardsiella tarda is a rare Gram-negative pathogen that uncommonly infects humans. Neonatal infections are extremely rare but often severe, with a high incidence of central nervous system (CNS) complications. Case presentation: We report a term neonate born via spontaneous vaginal delivery who developed systemic signs of infection within 18 h of life. Blood and cerebrospinal fluid (CSF) cultures grew Edwardsiella tarda. CSF analysis revealed severe meningoencephalitis. Maternal stool culture was also positive for E. tarda, suggesting vertical transmission. Despite initial systemic antibiotic therapy with ampicillin, gentamicin, and ceftriaxone, neuroimaging revealed progressive multifocal brain abscesses. The infant underwent a series of neurosurgical procedures, including bilateral drainage of abscesses, Rickham reservoir placement and ventriculoperitoneal shunting. A revised antibiotic regimen, including systemic meropenem and trimethoprim-sulfamethoxazole plus intrathecal gentamicin, was administered. At six months, the infant showed mild motor delay with lower limb hypertonia and was under close neurosurgical and developmental follow-up. Methods: We conducted a literature review of 12 published neonatal E. tarda infections, including our case. Results: Most infected infants presented within 72 h of life and exhibited CNS involvement. Mortality was 25%, and 44% of survivors experienced long-term neurologic sequelae. Conclusions: Edwardsiella tarda infection in neonates is rare but potentially devastating. Early suspicion, culture confirmation, aggressive antibiotic therapy, and multidisciplinary care, including neurosurgical management, are essential for improving outcomes. Full article

Background: Pediatric craniocervical junction (CCJ) anomalies consist of a unique subset of anatomically complex spine conditions. The aims of intervention are to achieve long-term stability, correct existing deformity, and prevent neurological compromise. However, surgery is challenging due to critical neurovascular and musculoskeletal structures in the limited operative space of a young child. Recently, the use of three-dimensional (3D) printed models has been demonstrated to be valuable neurosurgical adjuncts. We therein report the application of a 3D-printed model for a pediatric case with a complex CCJ condition. A systematic review of the related literature is concurrently performed. Case description: A 10-year-old male presented with torticollis associated with neck pain and progressive thoracic kyphosis. Neuroimaging reported an unfused os odontoideum inferior to the basion and anterior half of the C2 vertebral body and anteriorly angulated with the C1 anterior arch. Of note, there was a large vertebral vein coursing over the left C2 lamina that was predominantly draining into the CCJ venous plexus. A radiologically derived 3D model of the patient’s CCJ was printed and used for pre-operative planning, multi-disciplinary team discussion, and detailed counseling with the patient and caregivers. The patient underwent an uneventful C1–C2 posterior screw fixation and has recovered well since. Separately, we observed there is a paucity of publications specific to this topic. Conclusions: As demonstrated, a custom-made 3D model was useful for clinicians work through technical difficulties and improve the perioperative discussion process in an otherwise difficult case. Full article

Sensory processing differences, reported in up to 97% of individuals with autism spectrum disorder (ASD), are increasingly recognized as a defining feature of the condition, shaping perception, cognition, and adaptive behavior. Atypical sensory responsivity, ranging from hyper- to hypo-reactivity and sensory seeking, emerges early in development and contributes to the clinical and neurobiological heterogeneity of autism. Alterations in neural connectivity, the balance of excitation and inhibition, and multisensory integration are thought to underlie these sensory profiles, influencing emotional regulation, attention, and social interaction. Sensory features also interact with co-occurring conditions such as anxiety, attention deficit hyperactivity disorder, and sleep and feeding difficulties, thereby shaping developmental trajectories and influencing adaptive behavior. Clinically, these sensory dysfunctions have a significant impact on daily participation and quality of life, extending their effects to family functioning. Understanding individual sensory phenotypes is therefore essential for accurate assessment and personalized intervention. Current therapeutic approaches include Sensory Integration Therapy, Sensory-Based Interventions, Sequential Oral Sensory Approach, and structured physical activity programs, often complemented by behavioral and mindfulness-based techniques. Emerging neuroplasticity-oriented methods for targeted modulation of sensory processing networks include neurofeedback and non-invasive brain stimulation. Overall, current evidence highlights the central role of sensory processing in ASD and underscores the need for multidisciplinary, individualized approaches to optimize developmental trajectories and enhance adaptive functioning. This review provides an updated synthesis of sensory processing in ASD, integrating neurobiological, developmental, and clinical evidence to highlight established knowledge, unresolved questions, and priorities for future research. Full article

MEDNIK syndrome (Mental Retardation, Enteropathy, Deafness, Neuropathy, Ichthyosis and Keratodermia) is a severe hyper-rare condition resulting from the biallelic variants in the AP1S1 gene, implicated in intracellular trafficking and copper homeostasis. Only 18 affected individuals (seven AP1S1 pathogenic variants overall) have been reported to date, with a high early lethality due to life-threatening congenital enteropathy. Seven patients have been empirically treated with zinc. Due to the paucity of literature data, little is known about the clinical course of individuals affected by MEDNIK syndrome, and the possible early association with epilepsy needs to be investigated. We present the first case of Italian origin affected by MEDNIK syndrome carrying a new homozygous AP1S1 stop variant, presenting with congenital severe enteropathy and feeding-related seizures, thus representing an early, singular manifestation of the disease. We describe her clinical course and the zinc acetate therapeutic experience. We also reviewed the literature focusing on clinical manifestations (especially neurological), brain neuroimaging and the symptom evolution of patients with AP1S1-related MEDNIK syndrome and discuss possible future therapeutic attempts. Full article

Background/Objectives: Scheie syndrome is the attenuated phenotype of mucopolysaccharidosis type I (MPS I), a lysosomal storage disorder resulting from partial deficiency of α-L-iduronidase. The attenuated clinical spectrum and absence of cognitive impairment often delay recognition. Early manifestations may mimic common pediatric conditions, leading to repeated evaluations without a definitive diagnosis. Methods: We describe a 12-year-old girl who presented with slowly progressive bilateral hand stiffness, weak grip strength, and intermittent sensory symptoms over one year. Her initial investigations—including laboratory studies, electrophysiology, imaging, and multispecialty evaluations—were unremarkable. Results: The gradual progression of symptoms involving joints, motor function, and vision prompted metabolic testing. Whole exome sequencing revealed a homozygous IDUA variant, and enzymatic testing confirmed markedly reduced α-L-iduronidase activity, establishing the diagnosis of Scheie syndrome. Early initiation of enzyme replacement therapy was pursued. Conclusions: This case emphasizes that children with unexplained musculoskeletal and sensory symptoms should be evaluated for attenuated MPS I, especially when routine studies are inconclusive. Heightened clinical suspicion can reduce diagnostic delay and improve long-term outcomes. Full article

Background and Objective: Lennox–Gastaut syndrome (LGS) is a severe developmental and epileptic encephalopathy characterized by multiple seizure types, distinctive electroencephalography (EEG) abnormalities, and cognitive impairment. Sleep disturbances are highly prevalent in LGS and contribute substantially to reduced quality of life. However, no comprehensive analysis has yet been conducted to systematically examine key aspects of sleep—including architecture, microstructure, sleep-disordered breathing, and circadian regulation—leaving critical knowledge gaps. To address this, we conducted a scoping review to map the current evidence on sleep abnormalities in LGS and to identify priorities for future research. Method: A scoping review was conducted following PRISMA-ScR guidelines. PubMed, Embase, Ovid, and ClinicalTrials.gov from inception to October 2025 for studies evaluating sleep parameters in individuals with LGS or mixed epilepsy cohorts with ≥50% LGS cases. Eligible designs included observational and interventional studies using polysomnography, video-EEG, actigraphy, or sleep questionnaires. Data were synthesized narratively due to heterogeneity, and methodological quality was assessed using relevant Joanna Briggs Institute (JBI) checklists. Results: After screening 1242 articles, eleven studies met inclusion criteria, spanning 1986–2025 and conducted across four continents. Most were small single-center observational studies (5–16 LGS participants) using polysomnography as the primary assessment, with others employing wearable monitoring, surface and intracranial EEG, or circadian biomarker analyses. Across studies, individuals with LGS demonstrated markedly disrupted sleep architecture—notably reduced or absent rapid eye movement (REM) sleep, fragmented non-rapid eye movement (NREM) sleep, and attenuated spindles. Microstructural analysis showed elevated cyclic alternating pattern (CAP) rates, with epileptiform discharges clustering in CAP phase A. Sleep-disordered breathing (SDB) was common, particularly in adults, and associated with tonic seizures and central apneas. Circadian rhythm dysregulation, including altered melatonin and cortisol profiles, was also reported. A feasibility study demonstrated that home-based wearable devices and sleep apnea monitors were both acceptable and practical for use in children with LGS. No interventional studies have evaluated whether addressing sleep abnormalities modifies seizure or cognitive outcomes. Interpretation: Sleep in LGS is profoundly disrupted at both macrostructural and microstructural levels. These abnormalities may exacerbate seizure burden, cognitive impairment, and SUDEP risk, representing a potentially modifiable contributor to disease severity. Larger, prospective studies integrating polysomnography, wearable monitoring, and interventional approaches are needed to clarify causal mechanisms and therapeutic potential. Full article

Objectives: Atypical eating habits frequently characterize people with Autism Spectrum Disorder (ASD) from early infancy. Food selectivity, defined as a narrow variety of food intake and reticence to new food, is the most frequent feeding disorder in ASD. The objective of this study was to investigate the adaptive functioning and the behavioral profile of individuals with ASD with food selectivity (FS) in comparison to an ASD sample without food selectivity (NFS). Methods: We conducted a retrospective study on 286 children (mean age = 46.95 months) with a diagnosis of ASD; 43.3% of the sample had a history of food selectivity (FS), whereas 56.6% had no history of food selectivity (NFS). Results: No differences were found between the FS and NFS groups on cognition, autism symptom levels, and age. The FS group presented lower adaptive skills and greater behavioral problems in comparison to the NFS group. A worse clinical profile characterized children with more than one kind of food selectivity. Conclusions: The early identification and longitudinal evaluation of specific clinical and behavioral patterns in children with ASD associated with food selectivity could contribute to a better understanding of the relationship between autism symptoms and atypical eating habits. Full article

Marinesco–Sjögren syndrome (MSS) is a rare autosomal recessive disorder characterized by cerebellar ataxia, congenital cataracts, developmental delay, hypotonia, and progressive myopathy. Most reported cases are linked to pathogenic variants in SIL1, a gene encoding a co-chaperone essential for protein folding in the endoplasmic reticulum. Here, we present a comprehensive case study of a Turkish pediatric patient diagnosed with MSS, supported by genetic, bioinformatic, and structural modeling analyses. Whole-exome sequencing revealed a homozygous splice-site variant (SIL1 c.453+1G>T), confirmed by Sanger sequencing and segregation analysis. In silico annotation using Genomize, InterVar, Franklin, VarSome, ClinVar, OMIM, and PubMed classified the variant as pathogenic according to ACMG guidelines. Structural modeling by Phyre2 and I-TASSER demonstrated that the variant abolishes the intron 5 donor site, leading to truncation of the wild-type 461-amino-acid protein into a shortened ~189-amino-acid polypeptide. This truncation results in the loss of critical Armadillo (ARM) repeats required for HSPA5 interaction, explaining the observed instability and impaired chaperone function. Clinically, the patient presented with congenital cataracts, ataxia, developmental delay, and progressive muscle weakness, consistent with previously reported MSS cases. Comparison with the literature confirmed that splice-site variants frequently correlate with severe phenotypes, including early-onset ataxia and cataracts. This report highlights the importance of integrating genomic, structural, and clinical data to better understand genotype–phenotype correlations in MSS. Our findings expand the mutational spectrum of SIL1, reinforce the role of splicing defects in disease pathogenesis, and emphasize the necessity of comprehensive molecular diagnostics for rare neurogenetic syndromes. Full article

Background: Primary healthcare plays a vital role in delivering pediatric services. This study aimed to examine the epidemiology of pediatric visits to a model primary healthcare (PHC) center and identify factors associated with referrals to specialized care. Methods: A retrospective chart review was conducted for all pediatric visits between January and December 2024 at a model PHC center affiliated with an academic medical city in the Kingdom of Saudi Arabia (KSA). Descriptive statistics, chi-squared tests, and multivariable logistic regression were used to assess predictors of referral. Diagnoses were categorized, and clinic types stratified to explore seasonal and diagnostic trends. Ethical approval was obtained prior to data access. Results: A total of 4520 pediatric visits were analyzed. Just over half of the patients were female, and the largest age group was school-aged children (38.1%). Visit frequency peaked in winter and spring. Most visits (78.4%) were first-time consultations, and the majority occurred in general family medicine clinics. Overall, 10.95% of visits resulted in referrals. Referrals were more common during outpatient consultations than urgent care visits and were strongly associated with specific diagnoses, particularly neurological (aOR = 11.73), eye (aOR = 8.77), ENT-related conditions (aOR = 7.73), and genitourinary or pubertal conditions (aOR = 6.60). Demographic variables such as sex and nationality were not significant predictors. Conclusions: The observed referral rate may indicate effective gatekeeping within Saudi primary care, though referral frequency alone cannot determine appropriateness. Enhancing diagnostic support and behavioral health integration could further optimize referral practices and support Vision 2030 goals for strengthened child health services. Full article

Objectives: Alexander disease (AxD) is a rare neurodegenerative disorder that represents a group of leukodystrophies with severe disability and premature death, mostly with an infancy/childhood onset. In rare cases of late-onset phenotypes, symptoms are often milder and difficult to diagnose. We present a diagnostic journey of a teenage male patient with a progressive gait disorder starting at the age of 13 years, with a final diagnosis of Alexander disease. Early in the course of the disease, the boy exhibited distinctive cognitive involvement and neuropsychological deterioration characterized by selective impairment of visual and long-term auditory memory, along with a decline in IQ but preserved reasoning abilities. Methods: The patient underwent an extensive neurological diagnostic workup, which included magnetic resonance imaging (MRI) of the brain, spine, and abdomen, as well as electrophysiological, metabolic, and biochemical tests. Numerous specialist consultations were conducted, including genetic, cardiology, ophthalmology, pulmonology, oncohematology, psychological, and speech–language pathology consultations. In addition, a focused literature review was performed using PubMed, Scopus, Web of Science, and Google Scholar with the search terms “Alexander disease,” “GFAP gene,” “late-onset,” “spastic paraplegia” and “GFAP variant p/Gly18Val”. Results: Whole exome sequencing revealed an extremely rare missense GFAP heterozygous variant NM_002055.5: c.54G>T (p/Gly18Val), confirming the diagnosis of AxD. Conclusions: The presented case highlights the importance of whole-exome sequencing in the diagnosis of unexplained otherwise neurological symptoms, such as progressive spastic paraplegia. Full article

Background/Objectives: Vitamin B12 (B12) is essential for the provision of methyl groups for numerous essential pathways. Infant B12 deficiency (B12D) can lead to severe, even irreversible neurological abnormalities. Maternal B12 status in pregnancy and during the breastfeeding period correlates significantly with the child’s B12 status. B12D is a target disease in some newborn screening (NBS) programs. This study investigates whether infants that were clinically symptomatic and diagnosed with B12D in their first year of life could be retrospectively detected by the Austrian NBS algorithm. Methods: Data from infants with clinically diagnosed B12D in their first year of life between 2012 and 2022 were retrospectively collected in Austria (B12-related NBS implemented in 2018) and Switzerland (B12-related NBS not implemented). NBS data were retrospectively analysed, and clinical information was collected by a survey. Correlations between clinical symptoms, NBS data, biochemical parameters at diagnosis, maternal medical history and B12 status were analysed. Results: Four/forty-eight cases were retrospectively detected by the first-tier NBS parameters. From two children material for second-tier testing was available and B12D was confirmed by elevated total homocysteine (tHcy), resulting in a detection rate between 4.3 and 9.3%. The numbers of neurological and haematological symptoms correlated with low B12 and elevated levels of tHcy and methylmalonic acid. Although the detection rate of symptomatic B12D by NBS was low, fewer infants with symptomatic B12D were observed in the period after implementation of B12-related NBS (Austria). A history of B12D-relevant maternal disease such as pernicious anaemia was reported in 12 cases. Conclusions: B12D causes severe clinical symptoms in infants. NBS has a very limited retrospective detection rate of infants with severe B12D but seems to correlate with a reduction in cases due to not yet precisely quantified mechanisms. The workup triggered by NBS recalls is costly and often challenging for families. Maternal B12D increases the risk of infant B12D but also of other pregnancy-related health risks. To increase the efficacy of the prevention of infant B12D, to promote a healthy pregnancy and breastfeeding period, and to reduce the frequency of NBS recalls, pregnant women should be screened for B12D to be counselled and treated. Full article

Background: TCF20-associated neurodevelopmental disorder (TCF20-NDD) is a heterogeneous clinical condition resulting from defects in gene-encoding Transcription Factor 20, which plays a key role in neuronal development and synaptic function. Here, we present a novel case involving an 11-year-old boy who was referred to us for a neuro-developmental disorder characterized by attention deficit hyperactivity disorder (ADHD), tremor in the upper limbs, tilted head posture, motor delay, impaired executive functioning, and oculomotor dyspraxia. Methods: Genetic tests were performed, including CGH array, molecular analysis of the FMR1 gene, molecular analysis using a next-generation sequencing gene panel targeted for spinocerebellar diseases, and finally, WES including mitochondrial genome analysis. A neuroimaging study of brain and spine was performed using MRI. Results: Trio Whole Exome Sequencing revealed a de novo pathogenic frameshift variant NM_001378418.1:c.5009dup, p.(Thr1671Aspfs*5) in the TCF20 gene. The MRI scan of the brain, cervical, dorsal, and lumbosacral spine revealed Chiari type I malformation. Regarding the pathogenic mechanism underlying Chiari I malformation, it could be found in the homology between TCF20 and the RAI1 gene, the latter being associated with alterations in the posterior cranial fossa. Conclusions: We emphasize the use of exome sequencing in patients with unclear clinical presentations, with awareness of TCF20-associated neurodevelopmental disorder; paying attention to brain MRI findings would be useful to further expand the phenotype of TCF20-NDD. Full article