Search Results (116)

Leigh syndrome is a rare, progressive mitochondrial disorder of childhood. Early diagnosis is often challenging due to nonspecific clinical manifestations. We report a 1-month-old male infant initially referred for suspected congenital muscular torticollis who ultimately received a diagnosis of Leigh syndrome. Despite unremarkable perinatal history, he subsequently developed persistent feeding difficulties, recurrent vomiting, failure to thrive, and global developmental delay. Early neurological assessment revealed poor repertoire patterns on General Movement Assessment. The Neonatal Oral-Motor Assessment Scale (NOMAS) demonstrated dysfunctional oral-motor control, whereas the video fluoroscopic swallowing study (VFSS) revealed aspiration during swallowing. Brain MRI revealed symmetric basal ganglia lesions. Expanded whole-exome sequencing identified a pathogenic MT-ATP6 m.8993T>G variant with high heteroplasmy level (>90% in blood), confirming the diagnosis of Leigh syndrome. The variant was maternally inherited, although neither the mother nor the older sibling exhibited clinical features of mitochondrial disease. Leigh syndrome can initially manifest with subtle systemic features rather than overt neurological features. Persistent feeding difficulties and growth delay in infancy warrant thorough evaluation, including neuroimaging and comprehensive genomic testing, to enable timely diagnosis and optimize clinical management. Full article

Background: Beta-lactamase inhibitors (BLIs) are widely used with beta-lactam antibiotics to combat resistant infections, yet their safety profiles, especially for newer agents, remain underexplored. This study aimed to identify potential adverse event (AE) signals associated with BLIs using the USFDA Adverse Event Reporting System (USFDA AERS). Methods: The USFDA AERS was queried for AE reports involving FDA-approved BLIs from March 2004 to March 2024. After removing duplicates, only reports with BLIs listed as primary suspects were included. Disproportionality analysis was conducted using frequentist and Bayesian approaches, with statistical significance assessed by chi-square testing. Results: A total of 12,456 unique reports were analyzed. Common AEs across BLIs included hematologic disorders, hypersensitivity reactions, emergent infections, organ dysfunction, and neurological complications. Signal detection revealed specific associations: septic shock and respiratory failure with avibactam; lymphadenopathy and congenital anomalies with clavulanic acid; antimicrobial resistance and epilepsy with relebactam; disseminated intravascular coagulation and cardiac arrest with sulbactam; and agranulocytosis and conduction abnormalities with tazobactam. For vaborbactam, no distinct AE signals were identified apart from off-label use. Mortality was significantly more frequent with avibactam and relebactam (p < 0.0001). Conclusions: This analysis highlights a spectrum of AE signals with BLIs, including unexpected associations warranting further investigation. While some events may reflect comorbidities or concomitant therapies, these findings underscore the importance of continued pharmacovigilance and targeted clinical studies to clarify causality and ensure the safe use of BLIs in practice. Full article

SLC35A2-CDG is a congenital disorder of glycosylation caused by mutations in the SLC35A2 gene encoding a Golgi-localized UDP-galactose transporter. This transporter plays an essential role in glycan synthesis by transporting UDP-galactose from the cytoplasm into the Golgi lumen. Its dysfunction leads to impaired galactose-containing glycans and various neurological symptoms, although the underlying mechanisms remain largely unknown. We identified a novel SLC35A2-CDG patient carrying a pathogenic variant (c.617_620del, p.(Gln206ArgfsTer45)) who exhibited neurological abnormalities including bilateral ventriculomegaly. To investigate the disease mechanism, we established the first Drosophila model of SLC35A2-CDG. Knockout of Ugalt, the fly ortholog of SLC35A2, resulted in embryonic lethality, indicating its essential role. Knockdown of Ugalt reduced mucin-type O-glycans on muscles and neuromuscular junctions (NMJs), without affecting N-glycans. Ugalt knockdown larvae exhibited mislocalized NMJ boutons accompanied by a deficiency in basement membrane components on muscles. This phenotype resembles that of mutants of dC1GalT1 and dGlcAT-P, both involved in mucin-type O-glycosylation. Genetic interaction between Ugalt and dC1GalT1 was confirmed through double knockdown and double heterozygous analyses. Given that Drosophila NMJs are widely used as a model for mammalian central synapses, our findings suggest that Ugalt regulates NMJ architecture via mucin-type O-glycosylation and provide insights into the molecular basis of neurological abnormalities in SLC35A2-CDG. Full article

Background/Objectives: Perturbation in terminal N-glycan processing is a feature of congenital disorders of glycosylation and neurological disorders. Since treatment options are limited, N-glycans are plausible therapeutic targets. Here, we investigated the consequences of substituting complex/hybrid with oligomannose types of N-glycans on nervous and musculature systems, employing mgat1a and mgat1b mutant zebrafish models. Methods: CRISPR Cas9 technology was employed to engineer the mgat1a zebrafish model. The N-glycan populations in Wt AB, mgat1a−/− and mgat1b−/− zebrafish were characterized via lectin blotting. Motor and sensory functions were measured by tail-coiling and touch-evoked response assays in embryos and larvae. Swimming locomotion and anxiety-like behavior were characterized in adult Wt AB, and mutant zebrafish using motility and novel tank dive assays. Results: The mgat1a−/− model had increased oligomannosylated proteins compared to Wt AB in embryos and dissected brain, spinal cord, skeletal muscle, heart, swim bladder, and skin from adults, supporting a global knockdown of GnT-I activity. Higher levels were also observed in mgat1a−/− relative to mgat1b−/−, except in the brain. Band patterns for oligomannosylated proteins were different between all three zebrafish lines. The mgat1−/− embryos and larvae had deficient motor and sensory functions which persisted into adulthood, with a higher deficiency in mgat1b−/−. Anxiety-like behavior was decreased and increased in adult mgat1a−/− and mgat1b−/−, respectively, compared to Wt AB. Conclusions: Taken together, this study revealed that aberrant terminal N-glycan processing impacts brain, spinal and muscle control, and hence will enhance our understanding of the vital role of complex/hybrid N-glycans in nervous system health. Full article

Cytomegalovirus (CMV) represents the most prevalent cause of congenital viral infection in newborns and the leading non-genetic etiology of sensorineural hearing loss (SNHL) in children. Notably, only 10–15% of congenitally infected infants possibly present with classic clinical symptoms at birth, including Small for gestational age, Microcephaly, Petechiae or purpura, Blueberry muffin rash, Jaundice, Hepatomegaly, Splenomegaly and abnormal neurologic signs. In contrast, approximately 90% of infected neonates exhibit no apparent symptoms initially. Current research predominantly focuses on symptomatic cases due to their severe acute presentations and high rates of long-term sequelae (40–60%), including SNHL and neurodevelopmental impairments. However, significant controversy persists regarding the management of asymptomatic infants. Emerging evidence reveals that 8–15% of asymptomatic carriers develop Late-onset Hearing Loss (LOHL) beyond the neonatal period. Additionally, 5–10% may manifest neurodevelopmental abnormalities including mild intellectual disability, learning difficulties, or motor coordination disorders. Crucially, given the substantial population of asymptomatic cCMV cases, these delayed complications account for 30–40% of all cCMV-related long-term morbidity, underscoring their considerable public health impact. This review synthesizes current evidence and controversies regarding cCMV-related SNHL in asymptomatic or mildly symptomatic children, with a focus on screening, diagnostic classification, and antiviral management gaps, to heighten clinical awareness of this underrecognized cause of hearing loss. Full article

Miller–Dieker Syndrome (MDS) is a rare neurodevelopmental disorder caused by a heterozygous deletion of approximately 26 genes within the MDS locus of human chromosome 17. MDS, which affects 1 in 100,000 babies, can lead to a range of phenotypes, including lissencephaly, severe neurological defects, distinctive facial abnormalities, cognitive impairments, seizures, growth retardation, and congenital heart and liver abnormalities. One hallmark feature of MDS is an unusually smooth brain surface due to abnormal neuronal migration during early brain development. Several genes located within the MDS locus have been implicated in the pathogenesis of MDS, including PAFAH1B1, YWHAE, CRK, and METTL16. These genes play a role in the molecular and cellular pathways that are vital for neuronal migration, the proper development of the cerebral cortex, and protein translation in MDS. Improved model systems, such as MDS patient-derived organoids and multi-omics analyses indicate that WNT/β-catenin signaling, calcium signaling, S-adenosyl methionine (SAM) homeostasis, mammalian target of rapamycin (mTOR) signaling, Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling, and others are dysfunctional in MDS. This review of MDS integrates details at the clinical level alongside newly emerging details at the molecular and cellular levels, which may inform the development of novel therapeutic strategies for MDS. Full article

Hydrocephalus is a frequently observed congenital malformation of the central nervous system in domestic animals; however, its occurrence in wild species remains underreported. This study documents a clinical case of congenital hydrocephalus in a red fox cub (Vulpes vulpes) admitted to the “Visul Luanei” Wildlife Rehabilitation Center. The individual exhibited neurological deficits characterized by depressed mental status, incoordination, dromomania, behavior changes, and blindness. Diagnostic imaging, including radiography and magnetic resonance imaging (MRI), revealed a domed cranial morphology and severe dilation of the ventricular system. Notably, the lateral ventricles were markedly enlarged, with the absence of the septum pellucidum, resulting in a unified ventricular cavity. During electroencephalography (EEG) performed under general anesthesia, a high voltage and low frequency, predominantly featuring delta waves background activity was observed on all traces. Due to the poor prognosis and lack of clinical improvement, euthanasia was performed. This case contributes to the limited knowledge regarding central nervous system malformations in wild canids and underscores the need for further research on congenital neurological disorders in wildlife species. Full article

Background/Objectives: Neurodevelopmental disorders (NDDs) represent a clinically diverse group of conditions that affect brain development, often leading to varying degrees of functional impairment. Many NDDs, particularly syndromic forms, are caused by genetic mutations affecting critical cellular pathways. Ribosomopathies, a subgroup of NDDs, are linked to defects in ribosomal function, including those involving the synthesis of diphthamide, a post-translational modification of translation elongation factor 2 (eEF2). Loss-of-function (LoF) mutations in genes involved in diphthamide biosynthesis, such as DPH1, DPH2, and DPH5, result in developmental delay (DD), intellectual disability (ID), and multisystemic abnormalities. DPH5-related diphthamide deficiency syndrome has recently been reported as an ultrarare disorder linked to LoF mutations in DPH5, encoding a methyltransferase required for diphthamide synthesis. Methods: Clinical, neurological, and dysmorphological evaluations were performed by a multidisciplinary team. Brain MRI was acquired on a 3T scanner. Craniofacial abnormalities were assessed using the GestaltMatcher phenotyping tool. Whole exome sequencing (WES) was conducted on leukocyte-derived DNA with a trio-based approach. Bioinformatic analyses included variant annotation, filtering, and pathogenicity prediction using established databases and tools. Results: The affected subject carried a previously reported missense change, p.His260Arg, suggesting the occurrence of genotype–phenotype correlations and a hypomorphic behavior of the variant, likely explaining the overall milder phenotype compared to the previously reported patients with DPH5-related diphthamide deficiency syndrome. Conclusions: Overall, the co-occurrence of short stature, relative macrocephaly, congenital heart defects, variable DD/ID, minor skeletal and ectodermal features, and consistent craniofacial features suggests a differential diagnosis with Noonan syndrome and related phenotypes. Full article

Human cytomegalovirus (HCMV), a globally ubiquitous herpesvirus with the ability to carry out both lytic productive and lifelong latent infections, is a major cause of congenital infections, often leading to intellectual disabilities and neurological disorders. Moreover, HCMV is an opportunistic pathogen commonly found in immunocompromised individuals such as organ transplant recipients, HIV-positive individuals, and cancer patients, causing severe and life-threatening complications. While effective in inhibiting viral lytic infection, current FDA-approved compounds cannot eliminate the latent viral genome and have little effect on viral latent infection. Developing novel antiviral therapeutic approaches to eliminate HCMV lytic and latent infections is a major public health priority for controlling HCMV infection and preventing viral-associated diseases. The genome-editing technology based on the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein (Cas) RNA-guided nuclease system represents a novel and promising antiviral approach through modifying or destroying the genetic material of human viruses. This review summarizes the recently published progress in using the CRISPR-Cas approach to study and inhibit HCMV infections and discusses prospects for developing the CRISPR-based genome-editing technology for therapeutic applications against HCMV infection and associated diseases. Full article

Human cytomegalovirus (CMV) is the leading cause of congenital infections, often leading to mental retardation and neurological disorders. It is a major public health priority to develop a vaccine for preventing and controlling human CMV infection. In this report, we generated an oral Salmonella-based vaccine to express the M33 protein of murine cytomegalovirus (MCMV) and investigated the anti-MCMV immune responses induced in mice immunized with this vaccine. Compared to those administered with phosphate-buffered saline (PBS) or a control vaccine without M33 expression, mice immunized with the vaccine expressing the M33 protein exhibited a remarkable induction of antiviral serum IgG and mucosal IgA humoral responses and a significant elicitation of antiviral T cell responses. Successful inhibition of viral growth in lungs, spleens, livers, and salivary glands was also found in the vaccinated animals compared to the PBS-treated animals or those immunized with the control vaccine without M33 expression. Furthermore, substantial protection against MCMV challenge was observed in mice immunized with the vaccine. Thus, Salmonella-based vaccine expressing MCMV M33 can induce anti-MCMV effective immune responses and protection. Our study implies that attenuated Salmonella expressing human CMV antigens, including its homologue to M33, may represent promising oral anti-CMV vaccine candidates. Full article

Autosomal trisomy, a genetic disorder characterized by the presence of an extra autosome, is a rare but important chromosomal abnormality in horses, often associated with infertility, developmental abnormalities, and reduced life expectancy. This study represents the largest population-level screening for autosomal trisomy in horses; the analysis used single nucleotide polymorphism (SNP) panel genotype intensity data from 17,078 horses, 6601 of which were juveniles (i.e., ≤12 months of age) when genotyped. Using methodologies adapted from similar screening studies in cattle, the only aneuploidy detected was trisomy 27 in two juvenile male Irish Sport Horses (ISH) (0.03% prevalence among juveniles or 0.01% prevalence in the overall population). One ISH colt was cytogenetically confirmed and displayed no overt external phenotypic abnormalities, while cytogenetics was not undertaken on the other ISH colt, nor was it phenotypically assessed. Parentage analysis revealed that one ISH colt inherited two different copies of chr27 from the sire, demonstrating heterodisomy, likely due to a nondisjunction event during meiosis I in the sire. The other ISH colt inherited two different copies of chr27 from the dam, also indicating heterodisomy; the dam was 23 years of age when the colt was born. Based on the observed prevalence of autosomal trisomy, it can be estimated that at least 3 foals per 10,000 live births are likely to have autosomal trisomy. Though, given that only 74 (i.e., 0.004%) of horses were genotyped within a month of birth, this is likely an underestimate. The economic consequence of undiagnosed trisomy in high-value breeding horses that are potentially infertile could be substantial. As horse genotyping for parentage verification and discovery is transitioning to medium-density single nucleotide polymorphism panels, routine genomic screening for autosomal aneuploidy could be readily undertaken and potentially should form a standard screening prerequisite along with other genetic defects at horse sales. Currently, thoroughbred horses registered for racing are not genotyped, and only a limited number of sport horse studbooks are using SNP genotyping. This highlights an opportunity for those already genotyping to expand their support for breeders through low-cost, high-value chromosomal screening at the time of registration rather than incurring additional costs over the horse’s life cycle to determine the root cause of certain phenotypes owing to the undiagnosed trisomy. Full article

This case study presents the long-term management of a 14-year-old male diagnosed with 18q deletion syndrome, also known as de Grouchy Syndrome, highlighting the challenges of treating rare chromosomal disorders in rural Romania. Background and Clinical Significance: 18q deletion syndrome, also known as de Grouchy syndrome, is a chromosomal disorder caused by the deletion of a part of the long arm of chromosome 18. This syndrome is seen in one out of 10,000 live births. The main features of the syndrome are short stature, hearing loss, hypotonia, mental retardation, endocrine disorders, and autoimmunity. Case Presentation: The patient’s condition was initially suspected at birth due to abnormal features and was later confirmed through genetic testing, revealing a 46,XY,del(18) karyotype. Key clinical features include craniofacial dysmorphism, delayed growth, congenital cardiac anomalies, developmental delay, severe neurological impairment, and multiple comorbidities such as endocrine dysfunction, dental anomalies, and orthopedic deformities. Despite early interventions such as cardiac surgery, the patient’s management has been challenged by limited access to specialized care. Conclusions: The case underscores the importance of timely genetic testing, early multidisciplinary care, and the role of family support in managing complex disorders. This report also addresses the gaps in healthcare accessibility in rural settings and emphasizes the need for improved infrastructure and genetic services. By comparing this case with the existing literature, the study explores the variability in clinical presentations of 18q deletion syndrome and advocates for more precise genetic testing to better understand its phenotypic spectrum. The patient’s ongoing challenges with medical and socio-economic factors emphasize the critical need for coordinated care and family support in managing rare genetic conditions. Full article

Hemolytic anemias (HAs) encompasses a heterogeneous group of disorders with either congenital or acquired etiologies. We present a complex case of a 27-year-old woman with hemolytic anemia of multifactorial origin, involving both inherited RBC membrane defects and multiple autoimmune comorbidities. Genetic testing identified heterozygous variants in SPTA1 and SBDS, consistent with carrier status for hereditary elliptocytosis and Shwachman–Diamond syndrome. The patient was also diagnosed with Caspr2-positive Isaacs syndrome, systemic lupus erythematosus, seronegative antiphospholipid syndrome, and anti-aquaporin-4 antibody-positive optic neuritis. Despite extensive immunosuppressive and immunotherapic treatment and splenectomy, the clinical course was marked by recurrent hemolytic crises, thrombotic complications, and progressive neurological involvement, ultimately leading to death. Our experience highlights the challenges posed by the diagnosis and management of HAs, underlining the relevance of a multidisciplinary and personalized approach. Full article

Hemoglobin disorders are among the most common inherited diseases worldwide. Their clinical manifestations range from anemia to more severe forms associated with neurological impairments. These complications can result as secondary consequences of the disease’s clinical manifestations or be directly linked to genetic mutations. In this study, we present two families with neurological impairments who were referred to us for complementary hematological and biochemical analyses. Complete blood count, methemoglobin level, and methemoglobin reductase activity were assessed. Molecular analyses were performed using whole-exome sequencing, and the segregation of the identified mutations was confirmed with direct sequencing. Their pathogenicity and conservation were evaluated using various bioinformatics tools. Clinical and hematological findings suggested X-linked alpha-thalassemia/impaired intellectual development syndrome in the first family and recessive congenital methemoglobinemia type II in the second. This was confirmed by the identification of pathogenic mutations ATRX: p.Arg2131Gln and CYB5R3: p.Ala179Thr, respectively. Although these variants have been previously reported worldwide, they were identified for the first time in our population. Our results contribute to the understanding of the pathogenesis of these rare disorders and provide a basis for diagnosis, treatment, and genetic counseling. The mechanisms by which these mutations contribute to neurological symptoms are discussed. Full article

Background/Objectives: Iron is a fundamental micronutrient. Its deficiency could have a potentially harmful influence on maternal and fetal well-being. Methods: This review synthesizes current evidence on the epidemiology, consequences, and clinical meaning of iron deficiency (ID) and iron deficiency anemia (IDA) in pregnant women. Results: Untreated ID in pregnancy is associated with a wide spectrum of adverse outcomes: maternal clinical symptoms, cardiovascular disturbances, preterm birth, low birth weight, and impaired fetal neurodevelopment. Furthermore, ID has been related to impaired implantation, miscarriage, congenital heart defects, and neurological complications in fetuses. Women with gastrointestinal disorders and low socioeconomic status constitute a high-risk group of developing IDA. ID remains underdiagnosed and suboptimally managed in some clinical practices. Conclusions: This review highlights the critical importance of early detection, individualized supplementation, and public health interventions aimed at reducing iron deficiency during pregnancy. Full article