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PURPOSE: We aimed to determine the characteristics of epileptic seizures that significantly affect the cognitive functions of 83 patients followed with tuberous sclerosis complex (TSC), their resistance to treatment and risk factors causing this resistance. MATERIALS-METHODS: In order to determine the prognosis, the seizure-free/seizure-controlled group and the group with refractory seizures were compared. In addition, risk factors affecting cognitive functions in the patients were determined. RESULTS: There was a statistical significance between the presence of a history of seizures in the neonatal period, the age of onset of seizures being less than 2 years of age, autism, status epilepticus, Lennox-Gastaut syndrome (LGS), presence of infantile spasm, generalization of the electroencephalography (EEG) findings, the number of tubers in cerebral imaging being more than three and refractory seizures (p < 0.05). Statistically significant relationship was found between presence of a history of seizures in the neonatal period, the age of onset of seizures, autism, LGS, presence of infantile spasm, presence of status epilepticus history, history of using more than three antiepileptic drugs, generalization of EEG findings, presence of SEGA in cerebral imaging, number of tubers being more than three and the patient's mental retardation (p < 0.05). CONCLUSION: In logistic regression analysis, the age of the seizure onset being less than 2 years of age, the presence of autism and number of tubers being more than three in cerebral magnetic resonance imaging (MRI) are determined to be the risk factors that most likely to increase the seizures to be more resistant.
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Epilepsia Refractaria/etiología , Esclerosis Tuberosa/complicaciones , Adolescente , Edad de Inicio , Niño , Preescolar , Epilepsia Refractaria/patología , Femenino , Humanos , Lactante , Masculino , Pronóstico , Factores de Riesgo , Esclerosis Tuberosa/patologíaRESUMEN
Gaucher disease is the most common lysosomal storage disorder due to glucosylceramidase enzyme deficiency. There are three subtypes of the disease. Neurological involvement accompanies visceral and haematological findings only in type II and type III Gaucher patients. Type II is the acute progressive neuronopathic form which is the most severe and rare subtype. Clinical findings are recognized prenatally or in the first months of life and followed by death within the first two years of age. Among our 81 Gaucher patients, we identified 4 (4,9%) type II patients in our metabolic centre. This rate is significantly higher than the rate reported in the literature (<1%). Three of the patients had novel mutations, one of them was a collodion baby and the other one was mistyped as type III due to its atypical presentation at the beginning and he was treated with ERT for 8 months. In this report, we present our type II Gaucher patients with three novel mutations and one perinatal lethal form with generalized ichthyosis which is a very rare disorder. Additionally, we would like to highlight the phenotypic heterogeneity not only between the subtypes, also even in the same type.
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Enfermedad de Gaucher/genética , Glucosilceramidasa/genética , Mutación , Análisis Mutacional de ADN , Humanos , Lactante , Masculino , TurquíaRESUMEN
OBJECTIVE: Cardiac manifestations of neurofibromatosis type 1 (NF1) may include hypertension, congenital heart disease, and hypertrophic cardiomyopathy. The aim of this study was to evaluate cardiac abnormalities in patients with NF1. METHODS: Sixty-five NF1 patients (mean age: 9±4.48 years) were retrospectively studied. Standard electrocardiography and echocardiography were performed in all patients. RESULTS: Cardiac abnormalities were found in 11 of the 65 patients (15.3%). Five patients had mitral valve regurgitation, 2 patients had secundum atrial septal defect, 1 patient had pulmonary valvular stenosis, 1 patient had ventricular septal defect, 1 patient had tricuspid valve regurgitation, and 1 patient had aortic valve regurgitation. CONCLUSION: Cardiac abnormalities have potential long-term hemodynamic consequences that justify an early diagnosis. Thus, for any patient with NF1, a cardiologic assessment is mandatory at the time of diagnosis and with regular follow-up intervals.
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Cardiopatías/complicaciones , Cardiopatías/epidemiología , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/epidemiología , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios RetrospectivosRESUMEN
Global developmental delay (GDD)/intellectual disability (ID) is common in children and its etiology is unknown in many cases. Chromosomal abnormalities are predominant genetic causes of GDD/ID. The aim of this study is to determine the genetic risk factors that may be involved in the etiology of GDD/ID. In this study, 810 children with moderate to severe, clinically unexplained GDD/ID for whom cytogenetic analysis were performed were retrospectively rescreened. The results showed that GDD/ID affected more females than males (2 girls:1 boy). A total of 54 children (6.7%) with GDD showed chromosomal aberrations (CAs): 59.3% of these CAs were structural aberrations, and the rest were numerical aberrations (40.7%). Specifically, inversions, deletions, and reciprocal and robertsonian translocations, which were detected in 1, 0.7, 0.8, and 0.4% of the children, respectively, constituted important categories of structural CAs. Among numerical CAs, classic Turner and mosaics were detected in 1.2% of all children. Trisomy 21 and mosaic trisomy 21 were detected in 1% of the children. Marker chromosomes and 47,XXY karyotypes were found in two children each. Our results suggest that female sex is more affected by CAs among GDD/ID cases, and cytogenetic analysis is useful in the etiological diagnosis of GDD/ID.
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Spinal muscular atrophy (SMA) is a genetic disorder that causes progressive degeneration of lower motor neurons and the subsequent loss of muscle function throughout the body. It is the second most common recessive disorder in individuals of European descent and is present in all populations. Accurate tools exist for diagnosing SMA from genome sequencing data. However, there are no publicly available tools for GRCh38-aligned data from panel or exome sequencing assays which continue to be used as first line tests for neuromuscular disorders. This deficiency creates a critical gap in our ability to diagnose SMA in large existing rare disease cohorts, as well as newly sequenced exome and panel datasets. We therefore developed and extensively validated a new tool - SMA Finder - that can diagnose SMA not only in genome, but also exome and panel sequencing samples aligned to GRCh37, GRCh38, or T2T-CHM13. It works by evaluating aligned reads that overlap the c.840 position of SMN1 and SMN2 in order to detect the most common molecular causes of SMA. We applied SMA Finder to 16,626 exomes and 3,911 genomes from heterogeneous rare disease cohorts sequenced at the Broad Institute Center for Mendelian Genomics as well as 1,157 exomes and 8,762 panel sequencing samples from Tartu University Hospital. SMA Finder correctly identified all 16 known SMA cases and reported nine novel diagnoses which have since been confirmed by clinical testing, with another four novel diagnoses undergoing validation. Notably, out of the 29 total SMA positive cases, 23 had an initial clinical diagnosis of muscular dystrophy, congenital myasthenic syndrome, or myopathy. This underscored the frequency with which SMA can be misdiagnosed as other neuromuscular disorders and confirmed the utility of using SMA Finder to reanalyze phenotypically diverse neuromuscular disease cohorts. Finally, we evaluated SMA Finder on 198,868 individuals that had both exome and genome sequencing data within the UK Biobank (UKBB) and found that SMA Finder's overall false positive rate was less than 1 / 200,000 exome samples, and its positive predictive value (PPV) was 97%. We also observed 100% concordance between UKBB exome and genome calls. This analysis showed that, even though it is located within a segmental duplication, the most common causal variant for SMA can be detected with comparable accuracy to monogenic disease variants in non-repetitive regions. Additionally, the high PPV demonstrated by SMA Finder, the existence of treatment options for SMA in which early diagnosis is imperative for therapeutic benefit, as well as widespread availability of clinical confirmatory testing for SMA, warrants the addition of SMN1 to the ACMG list of genes with reportable secondary findings after genome and exome sequencing.
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BACKGROUND: The diagnosis of brain death is a clinical condition in which it is difficult to perform confirmatory tests due to the ineligible clinical status of the patient. Prior to confirmatory tests, the use of a BIS monitor to determine the time of brain death is important for organ transplants, cost-effectiveness and reducing stressful wait of the family. OBJECTIVE: This study aimed to use BIS monitoring for early detection of brain death. METHODS: BIS monitoring was performed in 12 patients who were clinically diagnosed with brain death in our intensive care unit during a two-year period. RESULTS: All patients had diffuse brain injury. The BIS score was zero in all patients. However, two patients could not be legally diagnosed with brain death because confirmatory tests could not be performed due to the clinical status. In one patient, the BIS score was zero and blood flow was present on the first computed tomography angiography of the brain; however, the cerebral blood flow was absent on the second imaging after two days. CONCLUSION: It was believed that BIS monitoring could be a parameter to use for detection of brain death in patients with severe brain injury. However, future research is needed in this regard.
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Muerte Encefálica , Electroencefalografía , Humanos , Muerte Encefálica/diagnóstico , Electroencefalografía/métodos , Encéfalo , Diagnóstico Precoz , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Myotonia congenita is the most common form of nondystrophic myotonia and is caused by Mendelian inherited mutations in the CLCN1 gene encoding the voltage-gated chloride channel of skeletal muscle. OBJECTIVE: The study aimed to describe the clinical and genetic spectrum of Myotonia congenita in a large pediatric cohort. METHODS: Demographic, genetic, and clinical data of the patients aged under 18 years at time of first clinical attendance from 11 centers in different geographical regions of Türkiye were retrospectively investigated. RESULTS: Fifty-four patients (mean age:15.2 years (±5.5), 76% males, with 85% Becker, 15% Thomsen form) from 40 families were included. Consanguineous marriage rate was 67%. 70.5% of patients had a family member with Myotonia congenita. The mean age of disease onset was 5.7 (±4.9) years. Overall 23 different mutations (2/23 were novel) were detected in 52 patients, and large exon deletions were identified in two siblings. Thomsen and Becker forms were observed concomitantly in one family. Carbamazepine (46.3%), mexiletine (27.8%), phenytoin (9.3%) were preferred for treatment. CONCLUSIONS: The clinical and genetic heterogeneity, as well as the limited response to current treatment options, constitutes an ongoing challenge. In our cohort, recessive Myotonia congenita was more frequent and novel mutations will contribute to the literature.
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Miotonía Congénita , Masculino , Humanos , Niño , Adolescente , Anciano , Lactante , Preescolar , Femenino , Miotonía Congénita/genética , Estudios Retrospectivos , Canales de Cloruro/genética , Mutación , Músculo EsqueléticoRESUMEN
Pontocerebellar hypoplasia (PCH) constitutes a heterogeneous neurodegenerative/neurodevelopmental disorder of the pons and cerebellum with onset in the prenatal period. Our study aimed to present different clinical and radiological manifestations of our genetically diagnosed PCH patients. METHOD: Six patients were enrolled in this study from September 2018 to March 2021. All the clinical radiological and genetic investigations were done at Cukurova University Medical School. RESULTS: Five children were diagnosed genetically and categorized under one of the types of PCH (type 10,7,11). Homozygous mutations in CLP1 In PCH type 10, TOE1 in PCH type 7, and TBC1D23 in PCH type 11 were respectively detected. Pateint with PCH type 11 and female patient with PCH type 7 could walk and speak few words. Male patient with PCH type 7 had disorder of sex development. CONCLUSION: According to our study, PCH is a rare neurodegenerative disease, although some types are static as PCH11 male gender and PCH7 female gender. Some clinical features are specific to a definite type. PCH7 express disorders of sex development most apparent in 46 XY. Some ethnic groups could express distinct subtypes. PCH10 is seen in the Turkish population. Radiological imaging is beneficial in pre-diagnosis; all the patients had different pons and cerebellar hypoplasia degrees. Genetic testing like whole exome sequencing -next-generation sequencing is essential in setting the definite diagnosis and determining the type/subtype of PCH.
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Enfermedades Cerebelosas , Malformaciones del Sistema Nervioso , Enfermedades Neurodegenerativas , Niño , Femenino , Humanos , Masculino , Mutación , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Malformaciones del Sistema Nervioso/genética , Proteínas Nucleares/genética , EmbarazoRESUMEN
Congenital Myasthenic Syndromes (CMS) are rare disorders that occur as a result of defects in the structure and in the function of neuromuscular junctions. Molecular genetic diagnosis is important to select the most suitable therapeutic option and treatment. Eight patients with congenital myasthenic syndromes who presented to the Çukurova University Pediatric Neurology Department Outpatient Clinic between June 2015 and May 2018 were reviewed. Mutations in the acetylcholine receptor (subunits in epsilon) (CHRNE) in three and mutations in the collagenic tail of endplate acetylcholinesterase (COLQ) gene in five patients were identified; p.W148 mutation was detected to be homozygous in four, c.1169A > G novel mutation in COLQ gene was homozygous in one, c452_454delAGG mutation was homozygous in the other patient, IVS7 + 2T > C(c.802 + 2T > C) mutation was homozygous in a patient and compound heterozygous mutations of c.865C > T(p.Leu289Phe) and c.872C > G(p.A2916)(p.Arg291Gly) in the CHRNE gene in the last patient. The parents of all the evaluated patients were consanguineous. Ptosis, ophthalmoplegia, generalized hypotonia, bulbar weakness, and respiratory crisis were the main findings at the time of presentation. Pyridostigmine is the first-line drug therapy in primary AChR deficiency. Beta adrenergic agonists, ephedrine, and albuterol are the other treatment options for CMS subtypes caused by mutations in COLQ. This study points out the genetic and phenotypic features of CMS patients in the Turkish population and it also reports previously unreported mutations in the literature. CHRNE and COLQ gene mutations are common in the Turkish population. Patients can get serious benefits and recover after the treatment. The treatment should be planned according to genetic tests and clinical findings.
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Síndromes Miasténicos Congénitos/diagnóstico , Síndromes Miasténicos Congénitos/genética , Adolescente , Agonistas Adrenérgicos beta/uso terapéutico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Síndromes Miasténicos Congénitos/tratamiento farmacológico , Estudios Retrospectivos , Factores de Tiempo , TurquíaRESUMEN
OBJECTIVES: Aldolase A deficiency also known as glycogen storage disease (GSD) XII, is an ultra rare autosomal recessively inherited GSD, associated with hemolytic anemia and rhabdomyolysis. CASE PRESENTATION: Here, we first report a patient with dermatological findings, hemodialysis requirement for rhabdomyolysis, and a novel likely pathogenic c.971C>T (p.A324V) mutation in the ALDOA gene. CONCLUSIONS: Episodes of rhabdomyolysis can be triggered by febrile illnesses and catabolic processes. Diagnosis should be confirmed by the mutation analysis of ALDOA gene. Treatment includes management of hemolytic anemia and administration of antipyretics during febrile episodes to avoid hemolysis and rhabdomyolysis.
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Anemia Hemolítica/etiología , Enfermedad del Almacenamiento de Glucógeno/complicaciones , Rabdomiólisis/etiología , Anemia Hemolítica/diagnóstico , Preescolar , Consanguinidad , Análisis Mutacional de ADN , Diagnóstico Diferencial , Fructosa-Bifosfato Aldolasa/genética , Enfermedad del Almacenamiento de Glucógeno/diagnóstico , Enfermedad del Almacenamiento de Glucógeno/genética , Humanos , Lactante , Masculino , Rabdomiólisis/diagnósticoRESUMEN
BACKGROUND: Levetiracetam (LEV) is a widely used antiepileptic drug (AED) in the treatment of various type of seizures, including generalized epileptic seizure as well as focal seizures, and it is generally well tolerated. Common side effects of LEV are somnolence, asthenia, dizziness, mood changes, kidney dysfunction, minor infections, and thrombocytopenia. Recently, increased creatine phosphokinase (CPK) concentration or rhabdomyolysis after LEV administration has been reported. The goal of the study was to evaluate clinical risk factors associated with increased CPK concentration or rhabdomyolysis in LEV administration. MATERIALS AND METHODS: One hundred and sixty children were enrolled. The risk factors were retrospectively analyzed. RESULTS: Among the 160 patients, 84 (52.5%) were boys and 76 (47.5%) were girls, and the mean age was 85.95 ± 49.03 months (9-188 months). Of the 160 patients, 66 (41.3%) were treated with monotherapy, and 94 (58.8%) with polytherapy. We detected increased CPK concentration or rhabdomyolysis in three patients (1.9%). The CPK values of these three patients were 943, 1504, and 5046, respectively. No significant differences were observed in the serum CPK concentration between the patients treated with LEV. CONCLUSION: We detected that LEV may cause increased CPK concentration or rhabdomyolysis. When treating patients with LEV, clinicians should closely monitor serum CPK level. To the best of our knowledge, this is the first study of elevated CPK concentration or rhabdomyolysis associated with LEV therapy in children.
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BACKGROUND: Autosomal recessive cerebellar ataxias (ARCAs) are a heterogeneous group of inherited neurodegenerative disorders. The aim of this study was to present the clinical and genetic features of patients with ataxia complaints and those genetically diagnosed with ARCAs. MATERIALS AND METHODS: Thirty-one children with ARCA were retrospectively analyzed. RESULTS: Fourteen (45.2%) were boys and 17 (54.8%) were girls with the mean age at onset of symptoms of 46.13 ± 26.30 months (12-120 months). Of the 31 patients, 21 (67.7%) were from consanguineous marriages. Eight patients had Friedreich's ataxia, five had ataxia telangiectasia, three had L-2-hydroxyglutaric aciduria, three had Joubert syndrome, two had neuronal ceroid lipofuscinosis, two had megalencephalic leukoencephalopathy with subcortical cysts, two had ataxia with ocular motor oculomotor apraxia type 1, one had cytochrome c oxidase deficiency, one had autosomal recessive spastic ataxia of Charlevoix-Saguenay, one had Niemann-Pick type C, one had congenital disorders of glycosylation, one had adrenoleukodystrophy, and one had cobalamin transport disorder. CONCLUSION: The prevalence of hereditary ataxia can vary among countries. The consanguineous marriage is an important finding in these diseases. These genetic tests will increase the number of ARCA patients diagnosed.
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Neurodegeneration with brain iron accumulation (NBIA) is a group of genetic disorders with a progressive extrapyramidal syndrome and excessive iron deposition in the brain, particularly in the globus pallidus and substantia nigra. Mitochondrial membrane protein-associated neurodegeneration (MPAN), a subtype of NBIA, is caused by mutation in the orphan gene C19orf12. A slowly progressive gait disorder from generalized dystonia and spasticity and cognitive impairment constitute the main features of MPAN. The C19orf12 p.Thr11Met mutation is frequent among Turkish patients with MPAN. Here, we report the clinical manifestations and genetic study results of six Turkish patients with MPAN due to different mutations from previous.
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Intrauterine infections with the pathogens, including toxoplasmosis, other (syphilis, varicella, mumps, parvovirus, and HIV), rubella, cytomegalovirus, and herpes simplex (TORCH) in susceptible individuals during pregnancy, result in microcephaly, white matter disease, cerebral atrophy, and calcifications in the fetus. Pseudo-TORCH syndrome is an umbrella term, consisting of several syndromes, resultant from different genetic alterations and pathogenetic mechanisms. Band-like calcification with simplified gyration and polymicrogyria (BLC-PMG) is one of these conditions, resultant from biallelic mutations in the OCLN gene, located in the chromosome 5q13.2. OCLN gene encodes occludin, a tight junction protein, which is expressed in the endothelia. The absence of occludin in the developing brain subsequently results in abnormal blood-brain barrier, thus immune-cell mediated tissue damage and cortical malformation. Herein, we present a pediatric patient who had progressive microcephaly, spasticity, multi-drug resistant epilepsy, PMG and intracranial band-type calcifications, accompanied by central diabetes insipidus and renal dysfunction. Whole exome sequencing revealed a homozygote W58Ffs*10 (c.173_194del) frameshift mutation in the OCLN gene. Of 34 BLC-PMG cases with demonstrable OCLN mutations, only three had renal manifestations, which is responsible for the majority of the demises. This is the first case diagnosed as having central diabetes insipidus and responded to desmopressin treatment to the best of our knowledge, however, this clinical improvement could not prevent the patient from renal dysfunction. The patient deceased at four years of age from sepsis, therefore early diagnosis, optimal follow-up for renal involvement and infection prevention measures are necessary for the patients with BLC-PMG.
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Enfermedades Autoinmunes del Sistema Nervioso/genética , Diabetes Insípida Neurogénica/genética , Malformaciones del Sistema Nervioso/genética , Ocludina/genética , Fenotipo , Defectos Congénitos del Transporte Tubular Renal/genética , Enfermedades Autoinmunes del Sistema Nervioso/patología , Diabetes Insípida Neurogénica/patología , Femenino , Mutación del Sistema de Lectura , Homocigoto , Humanos , Lactante , Malformaciones del Sistema Nervioso/patología , Defectos Congénitos del Transporte Tubular Renal/patologíaRESUMEN
Three prime repair exonuclease 1 (TREX1) degrades single- and double-stranded DNA with 3'-5' exonuclease activity. TREX1 mutations are related to type 1 interferon-mediated autoinflammation owing to accumulated intracellular nucleic acids. Several cases of systemic lupus erythematosus, Aicardi-Goutieres syndrome (AGS), familial chilblain lupus (FCL), and retinal vasculopathy-cerebral leukodystrophy caused by TREX1 mutations have been reported, so far. In this report, we described five patients with TREX1 mutations from three families with three different disorders, which include AGS, FCL, and FCL with central nervous system vasculitis.
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Duchenne muscular dystrophy (DMD) is a disorder that alter the expression of the dystrophin protein. Dystrophin deficiency alters the structural integrity of the contractile apparatus/sarcolemmal integrity, leading to dystrophic changes. Dystrophin deficiency results in an increase in oxidative stress. We aimed to investigate the thiol/disulfide balance as an oxidative stress marker in children with DMD. We included 24 DMD, and 22 healthy control group subjects in the study. The total thiol, native thiol, and disulphide levels were measured and the disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios were calculated in DMD patients and healthy subjects. The mean age distribution of the patients and the healthy control group subjects was similar. The total thiol, native thiol, and disulfide levels were lower in DMD group than the healthy controls. In conclusion, the markers and ratios were measured and calculated in the blood, and we detected that the total thiol, and native thiol levels were lower in DMD group than the healthy controls. These results indicate that dynamic thiol-disulphide homeostasis can be used as a marker of oxidative stress in clinical trials with DMD.
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Disulfuros/sangre , Homeostasis/fisiología , Distrofia Muscular de Duchenne/diagnóstico , Estrés Oxidativo/fisiología , Compuestos de Sulfhidrilo/sangre , Adolescente , Biomarcadores/sangre , Niño , Femenino , Humanos , Masculino , Distrofia Muscular de Duchenne/sangreRESUMEN
Autosomal-recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is caused by mutations of the SACS gene, characterized by late-infantile-onset spastic ataxia and other neurological features. ARSACS has a high prevalence in northeastern Quebec, Canada. Recently, several ARSACS cases have been reported from outside Canada. We report typical clinical and neuroimaging features in a Turkish child, which confirmed genetic diagnosis of ARSACS.
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Antibodies against glutamic acid decarboxylase (GAD) are associated with various neurologic conditions described in patients including stiff person syndrome, cerebellar ataxia, refractory epilepsy, limbic and extralimbic encephalitis. GAD antibodies-related limbic encephalitis cases are well described; reports of extralimbic involvement are limited. We describe four cases of GAD antibody-related autoimmune encephalitis. Three of them had extralimbic involvement and only one had limbic encephalitis.
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Encéfalo/patología , Encefalitis/inmunología , Glutamato Descarboxilasa/metabolismo , Enfermedad de Hashimoto/inmunología , Encefalitis Límbica/metabolismo , Autoanticuerpos/inmunología , Autoanticuerpos/metabolismo , Encéfalo/inmunología , Niño , Encefalitis/diagnóstico , Encefalitis/patología , Femenino , Glutamato Descarboxilasa/inmunología , Enfermedad de Hashimoto/diagnóstico , Enfermedad de Hashimoto/patología , Humanos , Encefalitis Límbica/inmunología , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/inmunología , Enfermedades del Sistema Nervioso/patologíaRESUMEN
Leigh syndrome (LS) is a progressive neurodegenerative disease caused by either mitochondrial or nuclear DNA mutations resulting in dysfunctional mitochondrial energy metabolism. The onset of clinical features is typically between 3 and 12 months of age; however, a later onset has been described in a few patients. Complex I deficiency is reported to be the most common cause of mitochondrial disorders. We described a patient with a late-onset LS, who presented with gait ataxia, caused by complex I deficiency (NDUFV1 gene).