Clinical and Electrophysiological Features Predicting Response to Antiseizure Medications in Juvenile Absence Epilepsy.

BACKGROUND: We aimed to evaluate the clinical findings and electroencephalographic (EEG) characteristics of patients with juvenile absence epilepsy (JAE) and to determine the factors that predict response to antiseizure medications (ASMs) in JAE. METHODS: We reviewed the medical records of 29 patients with JAE. The patients who were seizure-free during the last 12 months of their follow-up and who did not have generalized spike waves on their last EEG were considered as the treatment-responsive group, and the patients whose clinical seizures persisted during the last 12 months of their follow-up or who had generalized spike waves on their follow-up EEGs were considered as patients who did not respond to ASMs. RESULTS: There were 29 patients, 20 girls and nine boys, with a mean age of 13.34 ± 2.17 years and a follow-up time of 32.1 ± 11.9 months. Twenty-two cases (75.8%) were evaluated as responsive to treatment. Generalized tonic-clonic seizures (GTCS) were statistically more common in patients who did not respond to ASM. Epileptic seizures began at a younger age in the group that responded to medication. Occipital intermittent rhythmic delta activity (OIRDA) in EEG was significantly higher in the group that responded to the medication. CONCLUSION: Our study shows that concomitant GTCS may predict poorer response to ASMs in JAE. Younger age at diagnosis and OIRDA on EEG may be associated with better response to treatment. Our findings need to be confirmed by further prospective and long-term studies.

Retrospective evaluation of Guillain-Barre syndrome in children: A single-center experience.

BACKGROUND: Although Guillain-Barré syndrome (GBS) is now the most common cause of acute flaccid paralysis in children, information on the long-term follow-up of GBS is still limited. Identification of prognostic factors can play an important role in treatment strategies and the follow-up of patients. This study aimed to evaluate the effectiveness of monitoring the GBS disability score (DS) in predicting morbidity and mortality. METHODS: The patients were separated into two groups those with DS≥ or <3 on admission. These groups were compared in respect of demographic data, clinical and laboratory findings, and the DS recorded on admission and at first, third, sixth, 12th, and 24th months. RESULTS: The study included 44 patients (54.5% male, 45.5% female) with a median age of 5 years. The most common involvements during the disease were weakness, ataxia, neuropathic pain, cranial neuropathy, respiratory distress, autonomic dysfunction, and psychiatric symptoms, respectively. In patients with a DS of ≥3, the time from onset of symptoms to hospital admission was shorter, and the length of hospital stay was longer. Children with back pain and autonomic dysfunction had a DS of ≥3. A high 3-month DS was found to be a significant predictor for the development of sequelae. CONCLUSIONS: Although progressive muscle weakness and inability to walk are the most common symptoms of GBS, it should be kept in mind that atypical manifestations such as hemiplegia and ophthalmoplegia may also occur. For an objective assessment of clinical improvement during follow-up, the DS for motor functions can be used.

Psychometric properties of the Turkish version of the Epilepsy Disclosure Scale - Youth and Parent Versions.

AIM: Due to reactions, such as being ridiculed, blamed, or rejected, children with epilepsy and their families may consider epilepsy as something to be ashamed of, and therefore both the child and parents hide the disease from other people. No valid and reliable measurement in Turkish language that evaluates the level of this behavior, which will greatly affect the management of epilepsy, in both children and parents has been found in the literature. This study was carried out to test the validity and reliability of the Epilepsy Disclosure Scale (EDS) - Youth and Parent Versions in Turkey. MATERIALS AND METHOD: A descriptive, comparative, correlational, and methodological design was used in the study. The study was carried out with 200 youth with epilepsy between the ages of 8 and 18, who were registered in the pediatric neurology outpatient clinic of a university hospital located in the western region of Turkey, and their parents. The study data were collected using a Descriptive Information Form and the Turkish version of the EDS-Y and the EDS-P. The data were evaluated using content validity index, explanatory and confirmatory factor analyses, Cronbach's alpha, split-half, and item-total score correlation. FINDINGS: The total explained variance of the Turkish version of the EDS-Y consisting of one sub-dimension and six items was determined as 53.55%, and the total explained variance of the Turkish version of the EDS-P consisting of one sub-dimension and six items was determined as 59.39%. Cronbach's alpha values were 0.864 for the overall Turkish EDS-Y and 0.881 for the EDS-P. According to the confirmatory factor analysis, the model fit indices of both scales were found to be above 0.90 and the factor loads of all items were greater than 0.40. CONCLUSION: The Turkish versions of the EDS-Y and EDS-P scales have acceptable internal consistency reliability and content and construct validity and can be used by health professionals to evaluate the concealment of epilepsy from the perspectives of both young people and parents.

Inflammation and endothelial dysfunction in pediatric migraine patients.

BACKGROUND: Inflammation and endothelial dysfunction are the suggested underlying mechanisms in migraine. Pentraxins, C-reactive protein, erythrocyte sedimentation rate, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio are good indicators of inflammation. Alterations in insulin levels and insulin sensitivity may trigger endothelial dysfunction. This study evaluates the association between migraine and serum biomarkers of inflammation and endothelial dysfunction in children. METHODS: Children with migraine and healthy subjects were recruited. Serum samples were obtained in an attack-free period. We collected data on serum levels of complete blood cell count, C-reactive protein, erythrocyte sedimentation rate, pentraxin-3, and data from biochemical investigations. We compared these with clinical data such as age, sex, disease duration, attack frequency, attack duration, analgesic use, family history, and Pediatric Migraine Disability Assessment Questionnaire scores. RESULTS: We assessed samples from 32 children (11 boys, 21 girls) with migraine and 19 healthy controls (8 boys, 11 girls). We found significantly higher pentraxin-3, insulin, and insulin resistance in patients with migraine (P = 0.001, P = 0.032, and P = 0.008, respectively). A positive directional correlation is found between pentraxin-3 and Pediatric Migraine Disability Assessment Questionnaire scores. The best cut-off values for pentraxin-3 is determined between 12.75 pg/mL to 15 pg/mL in migraineurs. CONCLUSIONS: In conclusion increased pentraxin-3 levels support the suggestions that inflammation plays a role in pediatric migraine. The vascular endothelial dysfunction is observed by a rise in insulin and insulin resistance levels. Our findings support the idea that ongoing inflammation and vascular endothelial dysfunction between attacks may play a role in migraine pathogenesis in children.

Benefits of ketogenic diet in a pediatric patient with Ehlers-Danlos syndrome and STXBP1-related epileptic encephalopathy.

PURPOSE/AIM: Ehlers-Danlos syndrome (EDS) is a hereditary connective tissue disease. Epilepsy is not a common neurological finding in EDS. Here we report a pediatric patient with EDS comorbid with STXBP1 related epileptic encephalopathy as 'electrical status epilepticus during slow-wave sleep (ESES)' and whose refractory epileptic seizures were controlled with ketogenic diet. CASE REPORT: A 6-year-old girl who had EDS presented with refractory seizures and worsening cognitive functions. Her sleep electroencephalography (EEG) revealed electrical status epilepticus during slow-wave sleep (ESES). The epileptic encephalopathy panel revealed a de novo c.560C > T (p.pro187Leu) heterozygous mutation in the STXPB1 gene. Ketogenic diet treatment was started for her refractory seizures and seizures stopped in the third month of the 3:1 classical ketogenic diet. CONCLUSION: Our case is remarkable due to the coexistence of EDS and epileptic encephalopathy as well as ESES findings in STXBP1-associated epileptic encephalopathy and is therefore presented. Ketogenic diet would be beneficial on the management of refractory seizures in STXBP1-related epileptic encephalopathy and ESES.

Psychometric properties of a Turkish version of the quality of life in childhood epilepsy questionnaire.

BACKGROUND: Epilepsy is a neurological disease that requires long-term treatment and monitoring and causes significant restrictions in physical, emotional, intellectual, and social life that negatively affect the quality of life of the individual. This study aimed to test the validity and reliability of the Quality of Life in Childhood Epilepsy Questionnaire in Turkey. METHODS: The study was conducted on 421 parents using a descriptive correlational method. The data of the study were collected using a Descriptive Information Form and the Quality of Life in Childhood Epilepsy Questionnaire. Data analysis and evaluation were performed using factor analysis, Cronbach's alpha, and item-total score correlation. FINDINGS: The scale consists of 16 items and four sub-dimensions. The four sub-dimensions recorded a variance of 87.83%. Cronbach's alpha coefficient of the Turkish version of the scale was 0.96. The two-month test-retest reliability evaluated with intra-class correlation was 0.85. Confirmatory factor analysis indicated, the model fit index results were recorded as follows: 0.93 as the Goodness-of-Fit Index; comparative fit index, 0.98 and non-normed fit index (NNFI), 0.97. CONCLUSIONS: The study determined that the Turkish version of the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-16) is a valid and reliable measurement tool when used to measure quality of life for Turkish children with epilepsy. PRACTICE IMPLICATIONS: It is recommended that the health-related quality of life should be evaluated to assess the treatment of children with epilepsy and to intervene early in potential risk factors associated with the disease management process. All healthcare professionals can use this scale in interventional studies aiming at evaluating or improving the quality of life of children with epilepsy.

Neuronal ceroid lipofuscinosis: genetic and phenotypic spectrum of 14 patients from Turkey.

INTRODUCTION AND PURPOSE: Neuronal ceroid lipofuscinoses (NCLs) is a group of congenital metabolic diseases where the neurodegenerative process with the accumulation of ceroid and lipofuscin autofluorescent storage materials is at the forefront. According to the age of presentation, NCLs are classified as congenital, infantile (INCL), late infantile (LINCL), juvenile (JNCL), and adult (ANCL) NCLs. In our study, it was aimed to discuss the clinical and molecular characteristics of our patients diagnosed with NCL. MATERIAL AND METHOD: This is a descriptive cross-sectional study which was conducted in 14 patients from 10 unrelated families who were diagnosed with different types of NCL based on clinical presentation, neuroimaging, biochemical measurements, and molecular analyses, at the department of pediatric metabolism between June 2015 and June 2020. RESULTS: A total of 14 patients were diagnosed with different types of NCL. Of those, 4 patients were diagnosed with NCL7 (4/14; 30%), 3/14 (23%) with NCL1, 3/14 (23%) with NCL2, 2/14 (14.2%) with NCL13, and 1/14 (7.1%) with NCL10. Eleven pathogenic variants were detected, 5 of which are novel (c.721G>T [p.Gly241Ter] and c.301G>C [p.Ala146Pro] in MFDS8 gene; c.316C>T [p.Gln106Ter] in PPT1 gene; c.341C>T [p.Ala114Val] in TPP1 gene; c.686A>T [p.Glu229Val] in CTSD gene) CONCLUSION: This study is one of the pioneer comprehensive researches from Turkey that provides information about disease-causing variants and clinical presentation of different and rare types of NCLs. The identification of novel variants and phenotypic expansion is important for genetic counselling in Turkey and expected to improve understanding of NCLs.

Clinical predictors of drug-resistant epilepsy in children

Background/aim: In up to 20% of epilepsy patients, seizures may not be controlled despite the use of antiepileptic drugs, either alone or in combination. These individuals are considered to have drug-resistant epilepsy. Drug-resistant epilepsy is usually associated with intellectual disability, psychiatric comorbidity, physical injury, sudden unexpected death, and low quality of life. Early detection and prediction of drug-resistant epilepsy are essential in determining the patient's most appropriate treatment option. This retrospective study aimed to determine the clinical, electroencephalographic, and radiological factors associated with medically intractable childhood seizures. Materials and methods: Data regarding 177 patients diagnosed with drug-resistant epilepsy were compared with 281 patients with drug-responsive epilepsy. Results: Univariate analysis showed that age at seizure onset, having mixed seizure types, history of status epilepticus, history of neonatal seizures, history of both having febrile and afebrile seizures, daily seizures at the onset, abnormality on the first electroencephalogram, generalized epileptic abnormality on electroencephalogram, abnormal neurodevelopmental status, abnormal neuroimaging, and having symptomatic etiology were significant risk factors for the development of drug-resistant epilepsy (p < 0.05). In multivariable analysis, having mixed seizure types, history of status epilepticus, having multiple seizures in a day, intellectual disability, symptomatic etiology, and neuroimaging abnormality remained significant predictors for developing drug-resistant epilepsy. Conclusions: In the course of childhood epilepsy, some clinical features may predict the outcome. Early identification of patients with high risk for drug-resistant epilepsy will help plan the appropriate treatment option. Further prospective studies should confirm these findings.

Zonisamide attenuates hyperoxia-induced apoptosis in the developing rat brain.

Oxygen therapy used in the treatment of perinatal hypoxia induces neurodegeneration in babies with immature antioxidant mechanisms. Zonisamide is a new antiepileptic drug used in childhood intractable seizures. Many studies demonstrated its neuroprotective effects. There is no study evaluating its effect on hyperoxic brain injury. The aim of this study was to investigate the neuroprotective effect of zonisamide on hyperoxia-induced neonatal brain injury. A total of 21 Wistar rat pups were used. The animals were divided into three groups: control group, hyperoxia group, and zonisamide-treated group. The zonisamide-treated group received an intraperitoneal injection of zonisamide. Zonisamide significantly preserved the number of neurons in CA1 and dentate gyrus parts of hippocampus, prefrontal, and parietal cortex. Zonisamide treatment also decreased the number of apoptotic neurons in all examined parts of hippocampus, prefrontal, and parietal cortex. We suggest that zonisamide treatment may be used as a neuroprotective agent in hyperoxic brain injury.

Carnitine palmitoyl transferase II deficiency in an adolescent presenting with rhabdomyolysis and acute renal failure.

The most common cause of recurrent rhabdomyolysis in childhood is inherited metabolic disorders. Carnitine palmitoyl transferase II (CPT II) deficiency is a lipidosis and is a common cause of inherited recurrent myoglobinuria. The disease is inherited in autosomal recessive trait, and the clinical phenotype ranges from a severe and multisystemic infantile form to a milder muscle form, which is characterized with rhabdomyolysis and myoglobinuria. Exercise, infection, fasting, and cold are the most important triggering factors of rhabdomyolysis in CPT II deficiency. The severity of attacks is highly variable and some of these attacks may be complicated by acute renal failure. We report a case of a 13-year-old girl with recurrent rhabdomyolysis due to CPT II deficiency whose last attack was complicated by acute renal failure.

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.

Incidental white matter lesions in children presenting with headache.

AIM: We aimed to describe the prevalence and significance of white matter lesions detected on magnetic resonance imaging (MRI) in children with headache. MATERIAL AND METHODS: Children who were admitted with the complaint of headache and had neuroimaging between December 2007 and June 2012 were included in the study. The clinical and neuroimaging data of the patients were retrospectively evaluated. MRI results of the patients were documented in detail. The patients with non-specific white matter lesions were called for a control visit, and current status of headache and neurological findings were determined. RESULTS: A total of 941 patients were included in the study. Sixty-one percent of the patients received cranial neuroimaging. 8.2% had only cranial computed tomography (CT), 7.5% had cranial CT and cranial MRI, and 84.3% had only cranial MRI. 22.1% of the patients had abnormal cranial MRI findings. The rate of incidental non-specific white matter changes detected in our study group was 23/527 (4.4%). Among the 23 patients, 12 (52.2%) were male and 11 (47.8%) were female. Fourteen (60.9%) had migraine without aura, 8 (34.8%) had tension-type headache, and 1 (4.3%) had migraine with aura. Mean age of patients at the time of imaging was 12.1 ± 3.4 years (range 4.0-16.0 years). All patients with non-specific white matter changes on MRI showed normal psychomotor development, and there was no history of seizures or head trauma. The physical and neurological examinations of all patients were normal. The mean clinical follow-up period of the patients was 16.8 ± 17.3 months (range 6-80 months). No patients showed neurological deterioration during the follow up. The white matter lesions were supratentorial in all patients. The mean size of the lesions was 5.1 ± 4.5 mm (minimum, 2 mm; maximum, 24 mm). Repeated radiological evaluations were performed in 11 (47.8%) of the patients. No new white matter lesions were detected in control MRI during follow up. CONCLUSION: Non-specific incidental white matter changes may be seen in children with headache. For normal clinical follow up, in the absence of evident benefits from repeated imaging studies, we suggest that repeated imaging studies are not warranted in every patient and should be tailored according to clinical course.

Phrenic nerve palsy associated with brachial plexus avulsion in a pediatric patient with multitrauma.

Although brachial plexus injury occurring during multitrauma is frequent in adults, it is rarely observed in childhood. The most common cause of pediatric traumatic brachial palsy is motor vehicle accidents followed by pedestrian struck. Generally, phrenic nerve palsy accompanying brachial plexus trauma is observed in 10% to 20% of cases, but it is overlooked because unilateral injuries are frequently asymptomatic. Severe unilateral phrenic nerve palsy accompanying brachial plexus avulsion is very rare. Here, we present a pediatric case of unilateral phrenic nerve palsy associated with respiratory distress and brachial plexus avulsion due to multitrauma.

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.

A rare central nervous system tumor of childhood with spongiform appearance on brain magnetic resonance imaging; primary diffuse leptomeningeal oligodendrogliomatosis.

Primary diffuse leptomeningeal oligodendrogliomatosis is a rare fatal tumor of childhood. Symptoms usually occur when the tumor causes hydrocephalus. Brain magnetic resonance imaging (MRI) may be nearly normal in the early stages of the disease, while hydrocephalus and multiple leptomeningeal cysts with spongiform appearance may appear later on. One may consider the diagnosis when radiologic findings become apparent with multiple leptomeningeal cysts. However, failure to recognize the imaging findings due to the rarity of the disease may delay the diagnosis. Here, we report a 3.5-year-old girl who presented with ataxia and vomiting and had a diagnosis of primary diffuse leptomeningeal glioneuronal tumor with remarkable brain MRI findings as diffuse multiple tiny cystic lesions on the brain and spinal cord. She benefited from radiotherapy and temozolomide treatment with remission of brain MRI findings. Increasing the number of reported cases will enable the elucidation of the disease's pathogenesis and the development of treatment protocols.

Evaluation of Quality of Life and Psychiatric Aspects of Children with Epilepsy and Their Families Using Self-assessment Questionnaires.

OBJECTIVE: The aim of this study was to compare sociodemographic characteristics, quality of life, and levels of depression and anxiety of children with epilepsy and their families with a healthy control group. MATERIALS AND METHODS: In this study, 60 epileptic children and their families were included. The data of these patients were compared with 51 healthy children and their families. The Children's Depression Inventory, Beck Depression and Anxiety Scale, State-Trait Anxiety Inventory for Children, KINDL General quality of life scale, KINDL-epilepsy module, and short form-36 were used to determine the depression, anxiety, and quality of life levels of children and parents. RESULTS: Depression and anxiety scale scores of the epilepsy group were statistically higher than the control group (P < .05). In the epilepsy group, the emotional well-being dimension on the KINDL parent scale and the total health, emotional well-being, family, and friends dimensions on the KINDL child scale were statistically lower than the healthy control group (P < .05). Short form-36 scores of the parents of the epilepsy group were statistically lower than the parents of the control group (P < .05). As the KINDL epilepsy quality of life dimension scores increased, the scores of the parental short form-36 quality of life scale scores increased. KINDL parental total scores were statistically lower in those with comorbidities than those without comorbidities. CONCLUSION: Monitoring for psychiatric comorbidities and quality of life status for both the child and the parents is recommended. Also, it should be emphasized that it would be more beneficial to use self-answered scales when assessing the quality of life of epileptic children.

A rare case of hypomyelinating leukodystrophy-14 benefiting from ketogenic diet therapy.

BACKGROUND: Hypomyelinating leukodystrophy-14 (HLD14) is a rarely seen neurodevelopmental disease caused by homozygous pathogenic ubiquitin-fold modifier 1 gene variants. The disease has an autosomal recessive inheritance. All patients with this condition reported to date have drug-resistant epilepsy. The posttranslational modification of proteins with ubiquitin fold modifier 1 is defective in these patients and is thought to be responsible for severe neurodevelopmental problems. There is no previous report on the effectiveness of the ketogenic diet in the treatment of drug-resistant epileptic seizures in this disease. Therefore, we present a pediatric case diagnosed with HLD14 and whose drug-resistant epileptic seizures were controlled by ketogenic diet therapy. CASE: The patient was a three-year-old male with drug-resistant epilepsy and developmental delay. His brain magnetic resonance imaging revealed cerebellar atrophy, periventricular white matter hypomyelination, and ventricular enlargement. Whole-exome sequencing analysis identified a homozygous pathogenic variant in the ubiquitin-fold modifier 1 gene on chromosome 13q13. Ketogenic diet therapy was initiated for his drug-resistant seizures and subsequently reduced seizure frequency by more than 75%. The patient is still on ketogenic diet therapy. CONCLUSIONS: Ketogenic diet therapy may be beneficial for seizure control in HLD14 patients with drug-resistant seizures.

Expanding the spectrum of VAC14 related pediatric-onset neurological disease; striatonigral degeneration with brainstem involvement.

VAC14 related childhood-onset striatonigral degeneration was first defined in 2016 in two unrelated children with sudden onset neurological disease and regression of developmental milestones. Up to now, 11 cases have been reported. VAC14 is a component of a trimolecular complex that tightly regulates the level of phosphatidylinositol 3,5-bisphosphate (PI (3, 5)P2) and PI (3, 5)P2 is critical for the survival of neural cells. Pathogenic VAC14 variants result in striatonigral degeneration chacterised by prominent vacuolation of neurons in basal ganglia. Here, we present a patient with a homozygous pathogenic VAC14 variant, whose symptoms started at an early age and who had both basal ganglia and brain stem involvement. Our case is one of the youngest patients in literature and involvement of the brain stem is defined for the first time in VAC14 related neurological disease.

A rare central nervous system tumor of childhood with spongiform appearance on brain magnetic resonance imaging; primary diffuse leptomeningeal oligodendrogliomatosis.

Primary diffuse leptomeningeal oligodendrogliomatosis is a rare fatal tumor of childhood. Symptoms usually occur when the tumor causes hydrocephalus. Brain magnetic resonance imaging (MRI) may be nearly normal in the early stages of the disease, while hydrocephalus and multiple leptomeningeal cysts with spongiform appearance may appear later on. One may consider the diagnosis when radiologic findings become apparent with multiple leptomeningeal cysts. However, failure to recognize the imaging findings due to the rarity of the disease may delay the diagnosis. Here, we report a 3.5-year-old girl who presented with ataxia and vomiting and had a diagnosis of primary diffuse leptomeningeal glioneuronal tumor with remarkable brain MRI findings as diffuse multiple tiny cystic lesions on the brain and spinal cord. She benefited from radiotherapy and temozolomide treatment with remission of brain MRI findings. Increasing the number of reported cases will enable the elucidation of the disease's pathogenesis and the development of treatment protocols.

The utility of next-generation sequencing technologies in diagnosis of Mendelian mitochondrial diseases and reflections on clinical spectrum.

OBJECTIVES: Diagnostic process of mitochondrial disorders (MD) is challenging because of the clinical variability and genetic heterogeneity of these conditions. Next-Generation Sequencing (NGS) technology offers a high-throughput platform for nuclear MD. METHODS: We included 59 of 72 patients that undergone WES and targeted exome sequencing panel suspected to have potential PMDs. Patients who were included in the analysis considering the possible PMD were reviewed retrospectively and scored according to the Mitochondrial Disease Criteria Scale. RESULTS: Sixty-one percent of the patients were diagnosed with whole-exome sequencing (WES) (36/59) and 15% with targeted exome sequencing (TES) (9/59). Patients with MD-related gene defects were included in the mito group, patients without MD-related gene defects were included in the nonmito group, and patients in whom no etiological cause could be identified were included in the unknown etiology group. In 11 out of 36 patients diagnosed with WES, a TES panel was applied prior to WES. In 47 probands in 39 genes (SURF1, SDHAF1, MTO1, FBXL4, SLC25A12, GLRX5, C19oRF12, NDUFAF6, DARS2, BOLA3, SLC19A3, SCO1, HIBCH, PDHA1, PDHAX, PC, ETFA, TRMU, TUFM, NDUFS6, WWOX, UBCD TREX1, ATL1, VAC14, GFAP, PLA2G6, TPRKB, ATP8A2, PEX13, IGHMBP2, LAMB2, LPIN1, GFPT1, CLN5, DOLK) (20 mito group, 19 nonmito group) 59 variants (31 mito group, 18 nonmito group) were detected. Seven novel variants in the mito group (SLC25A12, GLRX5, DARS2, SCO1, PC, ETFA, NDUFS6), nine novel variants in the nonmito group (IVD, GCDH, COG4, VAC14, GFAP, PLA2G6, ATP8A2, PEX13, LPIN1) were detected. CONCLUSIONS: We explored the feasibility of identifying pathogenic alleles using WES and TES in MD. Our results show that WES is the primary method of choice in the diagnosis of MD until at least all genes responsible for PMD are found and are highly effective in facilitating the diagnosis process.