Evaluation of the Patients with the Diagnosis of Pontocerebellar Hypoplasia: A Multicenter National Study.

Pontocerebellar hypoplasia (PCH) is a heterogeneous group of neurodegenerative disorders characterized by hypoplasia and degeneration of the cerebellum and pons. We aimed to identify the clinical, laboratory, and imaging findings of the patients with diagnosed PCH with confirmed genetic analysis. We collected available clinical data, laboratory, and imaging findings in our retrospective multicenter national study of 64 patients with PCH in Turkey. The genetic analysis included the whole-exome sequencing (WES), targeted next-generation sequencing (NGS), or single gene analysis. Sixty-four patients with PCH were 28 female (43.8%) and 36 (56.3%) male. The patients revealed homozygous mutation in 89.1%, consanguinity in 79.7%, pregnancy at term in 85.2%, microcephaly in 91.3%, psychomotor retardation in 98.4%, abnormal neurological findings in 100%, seizure in 63.8%, normal biochemistry and metabolic investigations in 92.2%, and dysmorphic findings in 51.2%. The missense mutation was found to be the most common variant type in all patients with PCH. It was detected as CLP1 (n = 17) was the most common PCH related gene. The homozygous missense variant c.419G > A (p.Arg140His) was identified in all patients with CLP1. Moreover, all patients showed the same homozygous missense variant c.919G > T (p.A307S) in TSEN54 group (n = 6). In Turkey, CLP1 was identified as the most common causative gene with the identical variant c.419G > A; p.Arg140His. The current study supports that genotype data on PCH leads to phenotypic variability over a wide phenotypic spectrum.

Optic neuritis in Turkish children and adolescents: A multicenter retrospective study.

BACKGROUND: Various etiologies may underlie optic neuritis, including autoantibody-mediated disorders described in the last decade. We re-examined demographic, clinical, laboratory features and prognostic factors in pediatric patients with autoimmune optic neuritis according to current knowledge. METHODS: Cases of pediatric ON from 27 centers in Türkiye diagnosed between 2009 and 2022 were included for retrospective evaluation. RESULTS: The study included 279 patients, 174 females and 105 males, with a female-to-male ratio of 1.65. The average age at onset was 12.8 ± 3.4 years, and mean follow-up, 2.1 years (range: 1-12.1 years). Patients <10 years old were grouped as "prepubertal" and those ≥10 years old as "others". The diagnoses made at the end of follow-up were multiple sclerosis associated optic neuritis (n = 90, 32.3 %), single isolated optic neuritis (n = 86, 31 %), clinically isolated syndrome (n = 41, 14.7 %), myelin oligodendrocyte glycoprotein antibody associated optic neuritis (n = 22, 7.9 %), and relapsing isolated optic neuritis (n = 18, 6.5 %). Predominant diagnoses were myelin oligodendrocyte glycoprotein antibody associated optic neuritis and acute disseminated encephalomyelitis associated optic neuritis in the prepubertal group and multiple sclerosis associated optic neuritis in the older group. Recurrences were observed in 67 (24 %) patients, including 28 with multiple sclerosis associated optic neuritis, 18 with relapsing isolated optic neuritis, 11 with myelin oligodendrocyte glycoprotein antibody associated optic neuritis, 8 with aquaporin-4 antibody related optic neuritis, and 2 with chronic relapsing inflammatory optic neuropathy. Recurrences were more common among female patients. Findings supporting the diagnosis of multiple sclerosis included age of onset ≥ 10 years (OR=1.24, p = 0.027), the presence of cranial MRI lesions (OR=26.92, p<0.001), and oligoclonal bands (OR=9.7, p = 0.001). Treatment in the acute phase consisted of intravenous pulse methylprednisolone (n = 46, 16.5 %), pulse methylprednisolone with an oral taper (n = 212, 76 %), and combinations of pulse methylprednisolone, plasmapheresis, or intravenous immunoglobulin (n = 21, 7.5 %). Outcome at 12 months was satisfactory, with 247 out of 279 patients (88.5 %) demonstrating complete recovery. Thirty-two patients exhibited incomplete recovery and further combination treatments were applied. Specifically, patients with relapsing isolated optic neuritis and aquaporin-4 antibody related optic neuritis displayed a less favorable prognosis. CONCLUSION: Our results suggest optic neuritis is frequently bilateral in prepubertal and unilateral in peri­ or postpubertal patients. Age of onset 10 or older, presence of oligoclonal bands, and brain MRI findings reliably predict the development of multiple sclerosis. The risk of developing multiple sclerosis increases mostly during the second and third years of follow-up. Relapsing isolated optic neuritis remains a separate group where the pathogenesis and outcome remain unclear. Investigation of predisposing and diagnostic biomarkers and long follow-up could help to define this group.

A multicenter study of radiologically isolated syndrome in children and adolescents: Can we predict the course?

OBJECTIVES: To evaluate clinical characteristics, imaging features and etiological profile of Radiologically Isolated Syndrome (RIS) along with clinical and radiological follow-up. METHODS: Demographic, clinical and radiological data of patients younger than 18 years fulfilling the criteria for RIS were retrospectively analyzed. RIS was defined by the detection of lesions meeting the revised 2010 McDonald Criteria for dissemination in space on magnetic resonance imaging (MRI) in the absence of any symptoms of demyelinating disease or an alternative cause for the MRI findings. RESULTS: There were total 69 patients (38 girls, 31 boys). The median age at index MRI was 15.7 years, and median follow-up time was 28 months. The most common reason for neuroimaging was headache (60.9%). A first clinical event occurred with median 11 months in 14/69 (20%) of cases. Those with oligoclonal bands (OCB) in cerebrospinal fluid (CSF) and follow-up longer than 3 years were more likely to experience a clinical event (p<0.05): 25% of those with OCB manifested clinical symptoms within the first year and 33.3% within the first two years compared to 6.3% and 9.4%, respectively in those without OCB. Radiological evolution was not associated with any variables: age, sex, reason for neuroimaging, serum 25-hydroxyvitamin D level, elevated IgG index, OCB positivity, total number and localization of lesions, presence of gadolinium enhancement, achievement of 2005 criteria for DIS and duration of follow-up. CONCLUSION: Children and adolescents with RIS and CSF OCB should be followed-up for at least 3 years in order to detect any clinical symptoms suggestive of a demyelinating event. Because disease-modifying treatments are not approved in RIS and no consensus report justifies their use especially in pediatric RIS, close follow-up of OCB-positive patients is needed for early recognition of any clinical event and timely initiation of specific treatment.

Successful treatment of acute myocardial injury of Duchenne muscular dystrophy with steroids: a case report.

BACKGROUND: Duchenne muscular dystrophy (DMD) is an X-linked muscular disease which is caused by the absence of dystrophin. Troponin elevation with acute chest pain may indicate acute myocardial injury in these patients. We report a case of DMD that presented with ACP and troponin elevation, who was diagnosed with acute myocardial injury, and successfully treated with corticosteroids. CASE PRESENTATION: A 9-year-old with DMD was admitted to the emergency department with the complaint of acute chest pain. His electrocardiogram (ECG) revealed inferior ST elevation and serum troponin T was elevated. The transthoracic echocardiography (TTE) demonstrated inferolateral and anterolateral hypokinesia with depressed left ventricular function. An ECG-gated coronary computed tomography angiography ruled out acute coronary syndrome. Cardiac magnetic resonance imaging revealed mid-wall to sub-epicardial late gadolinium enhancement at the basal to the mid inferior lateral wall of the left ventricle and corresponding hyperintensity on T2-weighted imaging, consistent with acute myocarditis. A diagnosis of acute myocardial injury associated with DMD was made. He was treated with anticongestive therapy and 2 mg/kg/day of oral methylprednisolone. Chest pain resolved the next day, and ST-segment elevation returned to normal on the third day. Troponin T decreased in the sixth hour of oral methylprednisolone treatment. TTE on the fifth day revealed improved left ventricular function. CONCLUSION: Despite advances in contemporary cardiopulmonary therapies, cardiomyopathy remains the leading cause of death in patients with DMD. Acute chest pain attacks with elevated troponin in patients with DMD without coronary artery disease may indicate acute myocardial injury. Recognition and appropriate treatment of acute myocardial injury episodes in DMD patients may delay the development of cardiomyopathy.

Evaluation of pediatric patients presenting with acute-onset unilateral transient acquired blepharoptosis / Avaliação de pacientes pediátricos apresentando blefaroptose transitória unilateral de início agudo

ABSTRACT Purpose: To evaluate the clinical features of pediatric patients with acute-onset, unilateral transient acquired blepharoptosis. Methods: In this retrospective study, the clinical records of patients between April 2015 and June 2020 were reviewed for evaluation of demographic features, accompanying neurological and ophthalmologic manifestations, symptom duration, etiological cause, and imaging findings. Patients with congenital and acquired blepharoptosis with chronic etiologies were excluded. Results: Sixteen pediatric patients (10 boys and 6 girls) with acquired acute-onset unilateral transient blepharoptosis were included in this study. The patients' mean age was 6.93 ± 3.16 years. The most commonly identified etiological cause was trauma in 7 patients (43.75%) and infection (para-infection) in 5 patients (31.25%). In addition, Miller Fisher syndrome, Horner syndrome secondary to neuroblastoma, acquired Brown's syndrome, and pseudotumor cerebri were identified as etiological causes in one patient each. Additional ocular findings accompanied blepharoptosis in 7 patients (58.33%). Blepharoptosis spontaneously resolved, without treatment, in all the patients, except those with Miller Fisher syndrome, neuroblastoma, and pseudotumor cerebri. None of the patients required surgical treatment and had ocular morbidities such as amblyopia. Conclusion: This study demonstrated that acute-onset unilateral transient blepharoptosis, which is rare in childhood, may regress without the need for surgical treatment in the pediatric population. However, serious pathologies that require treatment may present with blepharoptosis.

RESUMO Objetivo: Avaliar as características clínicas de pacientes pediátricos com blefaroptose adquirida unilateral, transitória e de início agudo. Métodos: Neste estudo retrospectivo, foram revisados prontuários clínicos entre abril de 2015 e junho de 2020. Os pacientes foram avaliados em termos de características demográficas, manifestações neurológicas e oftalmológicas associadas, duração dos sintomas, etiologia e achados de imagem. Foram excluídos pacientes com blefaroptose congênita e com blefaroptose adquirida de etiologia crônica. Resultados: Foram incluídos neste estudo 16 pacientes pediátricos (10 masculinos e 6 femininos) com blefaroptose adquirida transitória unilateral de início agudo. A média de idade dos pacientes foi de 6,93 ± 3,16 anos. As causas etiológicas mais comumente identificadas foram trauma em 7 pacientes (43,75%) e infecção (casos parainfecciosos) em 5 pacientes (31,25%). Além disso, a síndrome de Miller-Fisher, a síndrome de Horner secundária a neuroblastoma, a síndrome de Brown adquirida e pseudotumor cerebral foram determinados como causas etiológicas em um paciente cada uma. Achados oculares adicionais estavam associados à blefaroptose em 7 pacientes (58,33%). Foi observada a resolução espontânea da blefaroptose, sem tratamento, em todos os pacientes, exceto nos pacientes com síndrome de Miller-Fisher, neuroblastoma e pseudotumor cerebral. Nenhum paciente precisou de tratamento cirúrgico. Morbidades oculares, como ambliopia, não foram encontradas em nenhum paciente. Conclusão: Este estudo demonstrou que a blefaroptose transitória unilateral de início agudo, rara na infância, pode regredir sem a necessidade de tratamento cirúrgico na população pediátrica. No entanto, também não deve ser esquecido que patologias graves que requerem tratamento podem se apresentar com blefaroptose.

Evaluation of pediatric patients presenting with acute-onset unilateral transient acquired blepharoptosis.

PURPOSE: To evaluate the clinical features of pediatric patients with acute-onset, unilateral transient acquired blepharoptosis. METHODS: In this retrospective study, the clinical records of patients between April 2015 and June 2020 were reviewed for evaluation of demographic features, accompanying neurological and ophthalmologic manifestations, symptom duration, etiological cause, and imaging findings. Patients with congenital and acquired blepharoptosis with chronic etiologies were excluded. RESULTS: Sixteen pediatric patients (10 boys and 6 girls) with acquired acute-onset unilateral transient blepharoptosis were included in this study. The patients' mean age was 6.93 ± 3.16 years. The most commonly identified etiological cause was trauma in 7 patients (43.75%) and infection (para-infection) in 5 patients (31.25%). In addition, Miller Fisher syndrome, Horner syndrome secondary to neuroblastoma, acquired Brown's syndrome, and pseudotumor cerebri were identified as etiological causes in one patient each. Additional ocular findings accompanied blepharoptosis in 7 patients (58.33%). Blepharoptosis spontaneously resolved, without treatment, in all the patients, except those with Miller Fisher syndrome, neuroblastoma, and pseudotumor cerebri. None of the patients required surgical treatment and had ocular morbidities such as amblyopia. CONCLUSION: This study demonstrated that acute-onset unilateral transient blepharoptosis, which is rare in childhood, may regress without the need for surgical treatment in the pediatric population. However, serious pathologies that require treatment may present with blepharoptosis.

Vanishing white matter disease with different faces.

PURPOSE: The goal of this study was to better understand vanishing white matter (VWM) disease, which is one of the most common hereditary white matter disorders, and its relationship to radiologic features, genetic analyses, and clinical findings. METHODS: We performed a study on 11 patients to describe the clinical and neuroimaging features of VWM. Patients were grouped into "infantile," "early childhood," and "juvenile" based on their onset age. EIF2B1-5 genes encoding five subunits of eukaryotic translation initiation factor 2B (eIF2B) were analyzed in all patients with clinically suspected VWM disease. RESULTS: In brain magnetic resonance imaging (MRI), all patients showed white matter abnormalities with various degrees. The initial clinical presentation in five of patients was ataxia, with severe refractory epilepsy in three patients. In children with infantile-onset VWM, a rapid deterioration of motor function was detected, and the frequency of epilepsy was higher. Two patients showed manifestations of end-stage VWM disease, and one of them had chronic subdural hematoma. One of our patients and his father were diagnosed with Brugada syndrome. Sequencing of the exons and exon-intron boundaries of the EIF2B1-5 genes revealed mutations in the genes EIF2B5 (5 cases), EIF2B3 (3 cases), and EIF2B4 (2 cases). We also found a novel mutation in one patient: c.323_325delGAA in the EIF2B1 gene. CONCLUSIONS: In this study, in addition to classical clinical and radiological findings, we wanted to emphasize that we may be confronted with refractory epilepsy (early infancy), cardiac problems, and intracranial complications that may occur in advanced stages.

The effect of antiepileptic drugs on thyroid hormonal function: valproic acid and phenobarbital.

The aim of this study was to evaluate the thyroid function alterations in a group of epileptic children taking antiepileptic drugs. The study included a total of 183 pediatric epilepsy patients, aged 15 months-16 years, comprising 114 patients treated with valproic acid, 69 patients treated with phenobarbital, and 151 age-matched healthy volunteers as the control group. Serum levels of thyroid hormones were measured before the beginning of the antiepileptic therapy and after 12 months of treatment. Thyroid-stimulating hormone levels were significantly higher in the 12th month of phenobarbital and valproic acid treatment. The level of free triiodothyronine before treatment was higher in epileptic patients than in the control group. Subclinical hypothyroidism at month 12 was determined in 15.2% of the valproic acid group and in 2.9% of the phenobarbital group. When compared with the pre-treatment values, there was a statistically significant difference in the incidence of subclinical hypothyroid in the valproic acid group and no significant difference in the phenobarbital group. Symptomatic hypothyroidism was not detected. It was concluded that the thyroid functions of patients using valproic acid and phenobarbital for a long time should be regularly monitored.

Cerebral atrophy in 21 hypotonic infants with severe vitamin B12 deficiency.

AIM: Nutritional B12 deficiency is a treatable cause of neurodevelopmental delay in infants. We report 21 infants with developmental regression and brain atrophy as revealed using cranial magnetic resonance imaging (MRI), secondary to severe vitamin B12 deficiency. METHODS: Twenty-one infants aged 4-24 months with B12 deficiencies who were admitted to our clinic between May 2013 and May 2018 were included in the study. MRI, bone marrow aspiration and the Denver-II Developmental Screening Test were performed in all infants. RESULTS: The mean age of the infants was 12.3 months, and the mean B12 level was 70.15 ± 32.15 ng/L. Hypotonia and neurodevelopmental retardation, and anaemia were present in all patients. Their bone marrow examinations were compatible with megaloblastic anaemia. Twelve patients had microcephaly, seven had tremor and one patient died of severe sepsis. Almost all patients were fed with breast milk and their mothers were also malnourished. Nine (42.9%) of the patients were Turkish and 12 (57.1%) were Syrian. All patients had abnormal Denver-II Developmental Screening Test scores. Most patients had severe cortical atrophy, cerebral effusion, thinning of the corpus callosum and delayed myelinisation in cranial MRI. Treatment with B12 resulted in dramatic improvement in general activity and appetite within 72 h. Tremors resolved in all cases. CONCLUSION: Neurological findings and developmental delay related to nutritional B12 deficiency can be prevented without sequelae if diagnosed early. Screening and treating of mothers for this deficiency will contribute to the health of both the mother and their feeding infant.

Importance of Streptococci Infections in Childhood Neuropsychiatric Disorders.

Paediatric autoimmune neuropsychiatric disorders associated with streptococci (PANDAS) are important neuropsychiatric disorders in childhood. Streptococcus pyogenes infection associated with tics, obsessive-compulsive disorders, and chorea co-occurrence is important. Swedo et al. have increased the awareness of this situation since 1998. How streptococcal infections give rise to this condition is not clear yet, but the severity of the symptoms is reduced by the treatment of streptococcal infections is important. Eight-year- nine-month-old girl presented with complaints of a 2-year history of upper respiratory tract infections and increased severity of blinking of eyes, throat cleaning, tic disorder and obsession with hand cleaning. In addition, choreiform movements were present and fluoxetine did not improve the symptoms. The patient was followed-up and treated with PANDAS pre-diagnosis. Streptococcus treatment and prophylaxis decreased the patient's complaints. A six-year-four months old boy, admitted with abnormal hand and body movements, which increased severity after the school period, and causing deteriorated fine motor skills during infectious periods for two years. There were also complaints with vocal tics and obsessive-compulsive disorder in the form of throat cleaning. Treatment of S. pyogenes was administered in throat culture. After the penicillin prophylaxis, the complaints decreased. In this study, two patients were presented with choreiform movements, obsessive-compulsive disorder and tic disorder due to follow-up PANDAS diagnosis. PANDAS should be considered in children with neuropsychiatric disorders, especially symptoms associated with infection periods.

Acute Mercury Poisoning in a Group of School Children.

OBJECTIVE: Elemental mercury is a toxic liquid element that is used widely in the home, medicine, agriculture, and industry. It is readily vaporized and inhaled at room temperature. Thereby, inhalation can cause acute or chronic poisoning. Mercury can be found in environmental naturally find but some dangers sources give rise to contaminations. It can be very dangerous to all living organisms, especially children. METHODS: This study presents the features of mercury poisoning in a group of pediatric cases. Data were obtained for 29 pediatric cases exposed to elemental mercury in a high school chemistry laboratory in Turkey. Patients with a blood mercury level exceeding 10 µg/L or a urine mercury level exceeding 15 µg/L were considered to have mercury poisoning. The patients were treated with 2,3-dimercaptopropane sulfonic acid or D-penicillamine. RESULTS: Twenty-nine children with mercury poisoning were admitted to the hospital. The median duration of exposure was 58 (range, 15-120) minutes. Ten (29%) children were asymptomatic. Physical and neurological examinations were normal in 19 (65.5%) children. The most common presenting complaint was headache. The most common neurological abnormality, partly dilated/dilated pupils, was present in 9 (31%) children. Mercury levels were measured in blood samples every 5 days, and the median blood mercury level was 51.98 (range, 24.9-86.4) µg/L. There was a positive correlation between the duration of exposure and maximum blood/urine mercury levels (P = 0.001). CONCLUSIONS: Elemental mercury exposure is potentially toxic; its symptomatology varies, especially in children. Secure storage of mercury and other toxic substances and provision of information about this subject to individuals who might be exposed to mercury and their families might help to prevent mercury poisoning.

The Levels of Vitamin D, Vitamin D Receptor, Homocysteine and Complex B Vitamin in Children with Autism Spectrum Disorders.

OBJECTIVE: Autism spectrum disorder (ASD) is a complex neurodevelopmental syndrome with an increasingly prevalent etiology, yet not fully understood. It has been thought that vitamin D, complex B vitamin levels and homocysteine are associated with environmental factors and are important in ASD. The aim of this study was to examine serum vitamin D, vitamin D receptor (VDR), homocysteine, vitamin B6, vitamin B12 and folate levels in ASD. METHODS: In this study, serum vitamin D and VDR, homocysteine, vitamins B6, B12 and folate levels were determined in 60 patients with ASD (aged 3 to 12 years) and in 45 age-gender matched healthy controls. In addition, calcium, phosphorus and alkaline phosphatase, which are associated with vitamin D metabolism, were measured from serum in both groups. ASD severity was evaluted by the Childhood Autism Rating Scale (CARS). RESULTS: Serum vitamin D and VDR were substantially reduced in patients with ASD in comparision to control group. However, homocysteine level was significantly higher and vitamin B6, vitamin B12 and folate were also reduced in patients with ASD. Total CARS score showed a positive association with homocysteine and a negative correlation with vitamins D,B6, B12, folate and VDR. CONCLUSION: This comprehensive study, which examines many parameters has shown that low serum levels of vitamins D, B6, B12, folate and VDR as well as high homocysteine are important in the etiopathogenesis of ASD. However, further studies are required to define the precise mechanism(s) of these parameters and their contributions to the etiology and treatment of ASD.

Homocysteine, Pyridoxine, Folate and Vitamin B12 Levels in Children with Attention Deficit Hyperactivity Disorder.

BACKGROUND: In our study, we aimed to evaluate the serum homocysteine levels, pyridoxine, folate and vitamin B12 levels in children with attention deficit hyperactivity disorders (ADHD). SUBJECTS AND METHODS: This study included 30 newly diagnosed drug-naive children with ADHD (23 males and 7 female, mean age 9.3±1.8 years) and 30 sex-and age matched healthy controls. The diagnosis of ADHD was made according to DSM-V criteria. Children and adolescents were administered the Schedule for Affective Disorders and Schizophrenia for School Aged Children, Present and Lifetime Version, the Conners' Parent Rating Scale-Revised, Long Form, the Conners' Teacher Rating Scale and the Wechsler Intelligence Scale for Children Revised (WISC-R) for all participants. Homocysteine, pyridoxine, folate and vitamin B12 levels were measured with enzyme-linked immunosorbent assay. RESULTS: Homocysteine, pyridoxine, folate and vitamin B12 levels were significantly lower in children with ADHD compared with their controls (p<0.05). A positive significant correlation was observed between the all WISC-R scores and vitamin B12 level in patients (r=0.408, p=0.025). CONCLUSIONS: The results obtained in this study showed that reduced homocysteine, pyridoxine, folate and vitamin B12 levels could be a risk factor in the etiology of ADHD.

Idiopathic Unilateral Paralysis of the Palate in a Youth.

Unilateral isolated paralysis of the soft palate is a rare clinical entity that is associated with rhinolalia and the flow of nasal fluids from the nostril on the affected side. We report a case of a 17-year-old boy admitted complaining of nasal speech and drinks flowing into his right nostril. Most cases of soft palate palsy are idiopathic, whereas a few cases are caused by viral infections or tumors. We describe an isolated case of soft palate palsy with spontaneous recovery within 1 month.

Muscular Dystrophy: A Retrospective Evaluation of 15 Cases.

OBJECTIVES: The aim of this study was to investigate the clinical and laboratory findings of patients followed up with a diagnosis of Duchenne muscular dystrophy (DMD). METHODS: This retrospective study included 15 boys diagnosed with muscular dystrophy at the Pediatric Neurology Department between July 2008 and July 2016. The presenting symptoms; level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine kinase (CK); ophthalmological findings; echocardiography (ECHO) results; findings on brain magnetic resonance imaging (MRI); genetic analysis results; and muscular biopsy findings were evaluated. RESULTS: The mean age of the patients was 5.2±2.3 years (range: 11 months-8 years) and the mean age at the onset of DMD was 4.1±2.2 years (range: 10 months-6 years). The ALT level ranged between 67 and 527 IU/L, the AST between 44 and 455 IU/L, and the CK between 931 and 19,595 IU/L. The genetic analysis determined deletions in 12 (80%) and duplications in 2 (13%) patients. CONCLUSION: Parents with a DMD-affected child should be provided with genetic counseling in order to make decisions about future pregnancies.

Exome sequencing identifies a novel homozygous CLN8 mutation in a Turkish family with Northern epilepsy.

Neuronal ceroid lipofuscinosis (NCL), one of the most common neurodegenerative childhood-onset disorders, is characterized by autosomal-recessive inheritance, epileptic seizures, progressive psychomotor deterioration, visual impairment, and premature death. Based on the country of origin of the patients, the clinical features/courses, and the molecular genetics background of the disorder, 14 distinct NCL subtypes have been described to date. CLN8 mutation was first identified in Finnish patients, and the condition was named Northern Epilepsy (NE); however, the severe phenotype of the CLN8 gene was subsequently found outside Finland and named 'variant late-infantile' NCL. In this study, five patients and their six healthy relatives from a large Turkish consanguineous family were enrolled. The study involved detailed clinical, radiological and molecular genetic evaluations. Whole-exome sequencing and homozygosity mapping revealed a novel homozygous CLN8 mutation, c.677T>C (p.Leu226Pro). We defined NE cases in Turkey, caused by a novel mutation in CLN8. WES can be an important diagnostic method in rare cases with atypical courses.