Background. Prion diseases or transmissible spongiform encephalopathies are a group of neurodegenerative disorders characterized by rapidly progressive dementia and movement disorders. Prion diseases can be acquired, sporadic, genetic (inherited), and are characterized by the accumulation and aggregation of prions or abnormally coiled proteins. The diseases have a long incubation period (years) but progress rapidly after the manifestation of clinical symptoms. The most common human prion diseases are sporadic in nature. Prion diseases include sporadic Creutzfeldt – Jakob disease, as well as rare cases of sporadic fatal insomnia and variable protease-sensitive prionopathy. The diseases have a long incubation period (years), but progress rapidly after the manifestation of clinical symptoms. Fatal familial insomnia (Insomnia, fatal familial; OMIM: # 600072) is a rare autosomal dominant neurodegenerative disease with high penetrance and associated with mutation in PRNP gene.Results. The article presents clinical case of 15-year-old patient with severe mental development disorder, motor excitability, hyperactivity of sympathetic nervous system and insomnia. The previously described variant in PRNP gene (D178N) was detected by whole exome sequencing. Validation of the mutation in the proband and segregation analysis were carried out: mutation c.532G>A, Asp178Asn in PRNP gene was identified in the proband and his 50-year-old father, who had no signs of prion disease. at the time of the study. Additionally, adenine in the 358th position was found in a homozygous state, which is responsible for the frequent M129M polymorphism in Sanger sequencing of PRNP gene in the proband and his father.Conclusion. The description of the clinical case of fatal familial insomnia in Russia presented by the authors clearly shows the likely difficulties that doctors may face when examining such patients. The diagnosis (clinical, genetic using massively parallel sequencing methods) remains important in relation to medical genetic counseling and family planning, since methods of pathogenetic therapy for hereditary prion diseases have not currently been developed.

In most cases, variants of nucleotide sequence in the SEMA6B gene account for developing the phenotype of progressive myoclonus epilepsy and, to a lesser extent, developmental encephalopathy with or without epilepsy. Loss-of-function variants in nucleotide sequence localized mainly in exon 17 of the SEMA6B gene contribute to production of aberrant proteins with “toxic” functions. A clinical case of status epilepsy in a patient with a variant in the SEMA6B gene (c.2506delС; p.His836ThrfsTer136; NM_032108.4) is described in the article that expands our knowledge regarding the SEMA6B gene variants resulting in progressive myoclonus epilepsy.

Введение. Прионные заболевания, или трансмиссивные губкообразные энцефалопатии, – группа нейродегенеративных расстройств, характеризующихся быстро прогрессирующими деменцией и двигательными нарушениями. Прионные заболевания могут быть приобретенными, спорадическими, генетическими (наследоваться) и характеризуются накоплением и агрегацией прионов или аномально свернутых белков. Заболевания имеют длительный инкубационный период (годы), но быстро прогрессируют после манифестации клинических симптомов. Наиболее распространенные прионные заболевания человека носят спорадический характер. К прионным заболеваниям относятся спорадическая болезнь Крейтцфельдта – Якоба, а также редкие проявления спорадической бессонницы со смертельным исходом и вариабельная протеаз-чувствительная прионопатия. Фатальная семейная бессонница (Insomnia fatal familial; OMIM: # 600072) – редкое аутосомно-доминантное нейродегенеративное заболевание с высокой пенетрантностью, развивается вследствие миссенс-мутации в кодоне 178 (D178N) гена PRNP, локализованном на хромосоме 20. Результаты. В статье представлен клинический случай пациента 15 лет с выраженными нарушениями психического развития, двигательным возбуждением, гиперактивностью симпатической нервной системы и бессонницей. При проведении полноэкзомного секвенирования выявлен ранее описанный вариант в гене PRNP (D178N). Проведена валидация мутации у пробанда и сегрегационный анализ: мутация c.532G>A, Asp178Asn в гене PRNP выявлена у пробанда и его 50-летнего отца, у которого на момент исследования не было отмечено признаков прионного заболевания. Дополнительно при проведении секвенирования по Сэнгеру гена PRNP у пробанда и его отца был обнаружен в 358-м положении аденин в гомозиготном состоянии, отвечающий за частый полиморфизм М129М. Заключение. Представленное авторами описание клинического случая фатальной семейной бессонницы в России наглядно показывает вероятные сложности, с которыми могут столкнуться врачи при обследовании таких пациентов. Своевременная диагностика (клиническая, генетическая с использованием методов массового параллельного секвенирования) остается важной в отношении медико-генетического консультирования и планирования семьи, так как методов патогенетической терапии наследственных прионных заболеваний в настоящее время не разработано. Background. Prion diseases or transmissible spongiform encephalopathies are a group of neurodegenerative disorders characterized by rapidly progressive dementia and movement disorders. Prion diseases can be acquired, sporadic, genetic (inherited), and are characterized by the accumulation and aggregation of prions or abnormally coiled proteins. The diseases have a long incubation period (years) but progress rapidly after the manifestation of clinical symptoms. The most common human prion diseases are sporadic in nature. Prion diseases include sporadic Creutzfeldt – Jakob disease, as well as rare cases of sporadic fatal insomnia and variable protease-sensitive prionopathy. The diseases have a long incubation period (years), but progress rapidly after the manifestation of clinical symptoms. Fatal familial insomnia (Insomnia, fatal familial; OMIM: # 600072) is a rare autosomal dominant neurodegenerative disease with high penetrance and associated with mutation in PRNP gene. Results. The article presents clinical case of 15-year-old patient with severe mental development disorder, motor excitability, hyperactivity of sympathetic nervous system and insomnia. The previously described variant in PRNP gene (D178N) was detected by whole exome sequencing. Validation of the mutation in the proband and segregation analysis were carried out: mutation c.532G>A, Asp178Asn in PRNP gene was identified in the proband and his 50-year-old father, who had no signs of prion disease. at the time of the study. Additionally, adenine in the 358th position was found in a homozygous state, which is responsible for the frequent M129M polymorphism in Sanger sequencing of PRNP gene in the proband and his father. Conclusion. The description of the clinical case of fatal familial insomnia in Russia presented by the authors clearly shows the likely difficulties that doctors may face when examining such patients. The diagnosis (clinical, genetic using massively parallel sequencing methods) remains important in relation to medical genetic counseling and family planning, since methods of pathogenetic therapy for hereditary prion diseases have not currently been developed.

Purpose. The purpose of the publication was to conduct an epidemiological survey for a comprehensive study of the dental status in children with autism spectrum disorder to clarify the areas of medical and social work and the potential scope of dental intervention.Materials and Methods. We examined 98 children with autism spectrum disorders aged 3 to 7 years, 69 of them with temporary and 29 with mixed occlusion. A dental examination of patients was carried out, the state of oral hygiene, carious defects of the teeth, and the state of periodontal tissues were assessed. Results. It is shown that the state of oral hygiene in children with autism spectrum disorder is unsatisfactory. The need for dental care in 85±5.6% of patients was diagnosed; there was a high prevalence (78.6%) of caries of primary teeth against the background of a significant intensity of caries pathology (the share of the “D” component in the overall structure of caries intensity is 81±3.11%); The prevalence of gingivitis was 61%, and the proportion of children with healthy parodontium was 7.14%.Conclusion. The results of the study determine the need to provide children with autism spectrum disorders with qualified dental care and its significant volumes. A set of recommended therapeutic and preventive measures has been proposed, including strengthening oral hygiene with particular regard to the specific characteristics of the underlying disease (emphasis on the motivational factor, transferring manual actions to a game format, using gadgets), strengthening pathogenetic therapy with the daily use of remineralizing drugs, the use of special physical therapeutic techniques (programs) in combination with regular examinations at the dentist and an increase in the intensity of preventive measures.

Ketogenic diet (KD) whilst being an effective method of diet therapy for drug-resistant epilepsy (DRE) is nevertheless accompanied by a significant number of side effects that include the possibility for the delayed physical development in pediatric patients. The problem is multifactorial and is primarily associated with the non-physiological nature of the ketogenic diet itself. Foreign studies on the KD effect on the physical development in children are contradictory and there are none domestic ones. The purpose of this research was to study the dynamics of anthropometric parameters in children with DRE against the background of KD and to assess the possibilities of the alimentary factor in its improvement. Materials and methods used: single-center retrospective cohort study had been carried out on the basis of the Russian Federal Research Centre for Nutrition, Biotechnology and Food Safety (Moscow, Russia) in 2016-2024. The study included patients with an established diagnosis of DRE against the background of KD aged 1 to 18 y/o. Patients were monitored for 24 months as follows: quarterly during the first year and semiannually during the second year of observation, using anthropometric, clinical-laboratory and clinical-instrumental research methods. Results: by the 3rd month of KD, out of 174 pediatric patients, the diet was effective in 105 (60%); by 12th month, 100% control over attacks was achieved in 11 (6%). Analysis of anthropometric parameters made it possible to establish that at the initial point of observation, in accordance with the z-score of the body mass index (BMI), 108 (64%) had normal nutritional status, 22 (13%) had malnutrition and 40 (24%) were overweight/obese. When studying the dynamics of weight and height indicators of children who were on KD throughout the observation period, it was found that the median BMI z-score statistically significantly changed upward (p=0.047), which was largely due to growth retardation, with a decrease in the height/age z-score throughout the observation period (p<0.001). It was found that the protein component of the diet, as well as the level of ketonemia, have a significant impact on the dynamics of the BMI z-score in KD patients. The amount of protein in the diet at 6% to 7% of the energy value contributed to the maintenance of optimal growth parameters in children within this research. Conclusion: the significance of the BMI indicator in assessing the nutritional status over KD decreases against the background of growth retardation. Taking into account the value of the protein/energy indicator when calculating nutrition helps in maintaining of the physical development rate in such patients.

The article presents the clinical cases of 6 patients with epilepsy, psychomotor and speech developmental delay. The heterozygous variants of the nucleotide sequence in SPTAN1 gene were detected by whole exome sequencing. Mutations in SPTAN1 gene have been described in patients with developmental and epileptic encephalopathy 5 (ОMIM: 613477). The clinical history, electroencephalographic and magnetic resonance imaging data of our patients are similar in children with variants in SPTAN1 gene described previously. It was shown that variants in SPTAN1 gene located closer to the C-terminal region are associated with a more severe phenotype, whereas the variants near the N-region – with a milder course of the disease without structural brain anomalies. However, further research is necessary in the future to better understand genotype-phenotypic correlations in SPTAN1-associated encephalopathy.

Focal epilepsy is the most common type of epilepsy accounting for 60–70% of all cases of this pathology. We present two familial cases of focal epilepsy associated with a nucleotide sequence variant in DEPDC5 gene. Clinical and ancestry examination was performed by using instrumental (magnetic resonance imaging, video-electroencephalography) and genetic testing methods. The nucleotide sequence variants in DEPDC5 gene were found in two probands and paired fathers with epilepsy. Focal cortical dysplasia was detected only in the father of Proband 1 as well as Proband 2 with resistant epilepsy and severe cognitive deficit. Hence, such clinical cases confirm that pathogenic variants in DEPDC5 gene are related with familial focal epilepsy, which clinical manifestation may depend on the type of identified mutation. The study of genotype-phenotype correlations is necessary to apply proper therapy. Before surgical treatment of epilepsy, the genetic testing by whole exome or whole genome sequencing should be performed.

Focal epilepsy is the most common type of epilepsy accounting for 60–70% of all cases of this pathology. We present two familial cases of focal epilepsy associated with a nucleotide sequence variant in DEPDC5 gene. Clinical and ancestry examination was performed by using instrumental (magnetic resonance imaging, video-electroencephalography) and genetic testing methods. The nucleotide sequence variants in DEPDC5 gene were found in two probands and paired fathers with epilepsy. Focal cortical dysplasia was detected only in the father of Proband 1 as well as Proband 2 with resistant epilepsy and severe cognitive deficit. Hence, such clinical cases confirm that pathogenic variants in DEPDC5 gene are related with familial focal epilepsy, which clinical manifestation may depend on the type of identified mutation. The study of genotype-phenotype correlations is necessary to apply proper therapy. Before surgical treatment of epilepsy, the genetic testing by whole exome or whole genome sequencing should be performed.

Ketogenic diet (KD) refers to promising methods of treatment of epilepsy resistant to anticonvulsants. A clinical case of the use of KD in a child with drug resistant epilepsy (DRE) is presented. This clinical case demonstrates the effectiveness of KD in a child with DRE in the form of achieving 100% control over seizures and positive shifts in the psycho-motor development of the child and positive changes in the child’s psychomotor development while ensuring adequate physical health.

В последние десятилетия достижения в области применения полноэкзомных и полногеномных технологий секвенирования позволили идентифицировать большое количество генов, связанных с умственной отсталостью, включая редкие формы, в частности, ассоциированные с мутациями в гене QRICH1. Синдром Вервери-Брэди (СВБ; MIM# 617982) - редкий синдром с аутосомно-доминантным типом наследования, характеризуется нарушением интеллекта, задержкой речи и легкими дисморфическими чертами лица. Впервые в России представлено клиническое и молекулярное описание двух пациентов с эпилепсией, задержкой развития и речи, мягкими дисморфическими чертами лица. При полноэкзомном секвенировании выявлены варианты нуклеотидной последовательность в гене QRICH1 -миссенс-мутация (c.1711G>A; p. Asp571Asn) и мутация сдвига рамки считывания (c.1963_1964insT; p.Lys655IlefsTer). На сегодняшний день в мире зарегистрировано 38 пациентов с мутациями в гене QRICH1. Recent advances in sequencing technologies have enabled identification of multiple genes associated with intellectual disability disorders, including QRICH1 gene. Ververi-Brady syndrome (VBS; MIM: #617982) is a rare developmental disorder, characterized by mild developmental delay, mildly impaired intellectual development and speech delay and mild dysmorphic facial features. For the first time in Russia, clinical and molecular description of two patients with epilepsy, developmental and speech delay, and mild dysmorphic facial features is presented. The variants nucleotide sequence in QRICH1 gene - missense mutation (c.1711G>A; p. Asp571Asn) and frameshift mutations (c.1963_1964insT; p.Lys655IlefsTer) were detected by whole exome sequencing. To date, thirty-eight individuals have been reported with QRICH1 mutations in the world.

Objective: to confirm a therapeutic equivalence and similar safety profile of “Midazolam, oromucosal (buccal) solution” and “Sibazon, solution for intravenous and intramuscular administration” used in children aged from 1 year to 18 years suffering from primary generalized and bilateral tonic, clonic and tonic-clonic seizures.Material and methods. An open-label, randomized clinical trial on efficacy and safety was conducted with 25 patients having primary generalized and bilateral tonic, clonic and tonic-clonic seizures due to epilepsy or epileptic syndrome. The study used age-appropriate doses of Midazolam with a single buccal administration as well as diazepam (Sibazon) for single intramuscular administration. Midazolam dosing was as follows: 5 mg for children of the younger age group (1 tube-dropper 5 mg/ml), 7.5 mg for children of the middle age group (1 tube-dropper 5 mg/ml and 1 tube-dropper 2.5 mg/ml), 10 mg for older children (2 tube-droppers 5 mg/ml). The drug effectiveness was assessed by primary and secondary criteria. The number of cases of drug administration in each group was used as the primary criteria, in which the convulsions ended up within 10 minutes after using the drug and did not resume within 60 minutes after drug administration. The following criteria were used as secondary: no repeated convulsive seizures within 24 hours after drug administration, no repeated convulsive seizure within 48 hours after drug administration, time before repeated convulsive seizure within 48 hours after drug administration. Clinical assessment was carried out according to clinical data, electroneurophysiologic (electroencephalographic) studies, electrocardiography, clinical blood and urine tests, aswell as biochemical blood tests by measuring glucose, total protein, albumin, total bilirubin, cholesterol, aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase, alkaline phosphatase, creatinine, urea, and creatinine clearance level.Results. Compliance with the first efficacy criterion after using Midazolam and Sibazon was observed in 11 (84.6%) and 9 (75%) patients in Group 1 and Group 2, respectively, showing insignificant differences (Fisher's exact test (FET): p=0.645). The number of no cases of repeated convulsive seizure within 24 hours after drug administration differed significantly and was 12 (92.3%) and 6 (50%), respectively (FET: p=0.030). The number of cases with no second seizures within 48 hours after drug administration in Group 1 and Group 2 was 12 (92.3%) and 5 (41.7%), respectively, showing insignificant differences (FET: p=0.0112). No serious adverse events were reported during the study. No patients cancelled participation in the study due to developed adverse event.Conclusion. The data obtained evidence about compatibility of therapeutic efficacy profile and similar safety profile for “Midazolam, oromucosal (buccal) solution” and “Sibazon, solution for intravenous and intramuscular administration” that agrees with multiple data of earlier studies.

The article concentrates on the experience of using the ketogenic diet (KD) in neurological practice in children with epilepsy resistant to anticonvulsant treatment. Prescription of KD in combination with drug therapy or without it allowed to achieve 100% control over seizures (confirmed by electroencephalographic study), significant progress in psycho-speech, cognitive, motor development in 21% of cases, which increased the chances of socialization of children and improved family life quality.

A study of the clinical effectiveness of the method of plantar pneumostimulation in the rehabilitation of 82 children with spastic and atonic-astatic forms of infantile cerebral palsy, aged 11 months to 17 years, suffering from symptomatic epilepsy, was carried out. When using the assessment of dynamics using the GMFM-66 and GMFCS scales, positive dynamics in motor status was revealed, which turned out to be significant in the younger age group. The authors believe that the reason for this phenomenon is the application of proprioceptive-corrective action in the case of an incomplete process of neuroontogenesis, which allows the maximum use of the reserves of the child's plastic brain. All children underwent an electroencephalographic study before and after the course of plantar pneumostimulation, and in none of the cases there was no clinical or neurophysiological exacerbation of the epileptic process. A conclusion is made about the effectiveness and epileptological safety of the plantar pneumostimulation technique, which allows us to recommend it for widespread implementation in neurorehabilitation practice.

Objective: to prove the therapeutic equivalence and similar safety profile of “Sibazon, rectal solution” (international nonproprietary name: diazepam) and “Sibazon, solution for intravenous and intramuscular administration” in children with primary generalized and bilateral tonic, clonic and tonic-clonic seizures.Material and methods. An open-label, randomized clinical trial on efficacy and safety was conducted in 20 patients suffering from epilepsy with generalized seizures aged 1 to 17 years. Clinical blood and urine tests, biochemical blood analysis were used for diagnostics (glucose, total protein, albumin, total bilirubin, cholesterol, aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase, alkaline phosphatase, creatinine, urea, creatinine clearance), as well as data on electrocardiographic (ECG) and electroencephalographic (EEG) studies. The patients were divided into two groups: in Group 1 (n=8), a rectal solution was used, in Group 2 (n=12) – a solution for intravenous and intramuscular administration.Results. The number of cases in which seizures were completed within 10 minutes after using the drug without resuming within subsequent 60 minutes, in Group 1 was 7 (87.5%), and in Group 2 – 9 (75.0%) (Fisher exact test (FET): p=0.617). Repeated primary generalized or bilateral tonic/clonic/tonic-clonic seizures within 24 hours after drug administration, in Group 1 were absent in 5 (62.5%) patients, in Group 2 – in 6 (50%) (FET: p=0.670); within 48 hours after drug administration – in 5 (62.5%) and 7 (58.3%) children, respectively (FET: p=1.00). Physical examination revealed no pathology in all patients at the final visit. While comparing ECG and EEG data at the final visit, no inter-group differences were found by the number of children with deviations from the norm. The results of laboratory studies confirmed that using the studied drugs had no negative effect on the main indicators of clinical and biochemical blood tests as well as clinical urine analysis.Conclusion. The effectiveness of the rectal form of Sibazon in relieving pediatric generalized epileptic seizures is comparable to that of Sibazon for intramuscular administration. The drug rectal form, due to easy-to-use administration, is preferable for outpatient practice. “Sibazon, rectal solution” is safe and has good tolerability.

We present the clinical case of patient with epilepsy, developmental retardation and hearing loss. The whole exome sequencing allowed to reveal compound heterozygous variants of the nucleotide sequence in SPATA5 gene (c.1714+1G>A, c.1678G>A). Mutations in the SPATA5 gene have been described in patients with epilepsy, hearing loss and mental retardation syndrome (MIM 616577). Paired parents were carriers of one heterozygous gene variant. Such mutations lead to the development of epileptic disorders in 3% of cases, and should be considered in patients not only as a possible cause of neurodegenerative diseases, but also leading to pathology with clinical manifestations mimicking mitochondrial disease.

Autism spectrum disorders (ASDs) are a group of complex disintegrative disorders of mental development, characterized by a lack of ability to social interaction, communication, stereotyped behavior, leading to social maladaptation. We present a rare clinical case of a delay in psychomotor and speech development, specific facial dysmorphia, impaired behavior, and a detected mutation in the ADNP gene. When conducting targeted exomic sequencing, we revealed a previously undescribed variant of the nucleotide sequence in the ADNP gene (p.Ala1017fs). Mutations in the ADNP gene in a heterozygous state were described for patients with Helsmoortel-van der Aa syndrome (OMIM: # 615873). Mutations in the ADNP gene are the genetic cause of ASD in 0.17% of cases. When interpreting the data of new generation sequencing (NGS) in patients with epileptic encephalopathy, ASD, and characteristic phenotype, it is advisable to take into account that the ADNP gene is one of the key genes responsible for embryonic neurodevelopment.

Introduction . Epilepsy is a neurological disorder characterized by periodic seizure attacks. Around 70–80% of epilepsy cases have a hereditary component. Aim : to identify the genetic factors of pharmacoresistant epilepsy in children. Materials and methods . Fifty two patients with epilepsy and psychomotor / speech retardation were examined. We used the next generation sequencing (NGS) technique, which is the targeted exome sequencing, the “Hereditary epilepsy” panel of genes, and the whole exome sequencing assay. Results . Mutations were detected in 30 (57.7%) patients, while 22 patients had no mutations. In the latter cases, either epilepsy was of non-hereditary nature or the tested nucleotide sequence was located in the non-coding part of the gene (intron); in addition, a chromosomal rearrangement could be involved. Conclusion . The obtained data illustrate a diagnostic significance of the whole exome sequencing and encourage the interaction between an epileptologist and a geneticist in the diagnostic procedure. Identification of the genetic base of the disease is of great importance for genetic counseling and for selecting an antiepileptic therapy in this group of patients. The authors declare about the absence of conflict of interest with respect to this publication. Authors contributed equally to this article.

The article presents current dietetic approaches to organisation of a ketogenic diet (KD) in children with pharmacoresistant epilepsy. The indications, contraindications, side effects of KD are considered as well as methods of control over patients who receive ketogenic diet therapy, information recourses for it’s application are provided. Characteristics of KDs used in epilepsy are given – the classical, MCT, the Atkins modified diet, and a low-glycemic diet. The role of specialised food products designed for patients who need a ketogenic diet is outlined. The results of studying the actual nutrition of children with pharmacoresistant epilepsy who receive KD are indicative of a considerable decrease, as compared with the recommended allowances, of the levels of vitamins (С, В1, В2, folates, D3) and mineral substances (calcium, phosphorus, magnesium, iron, selenium). The results demonstrate good prospects for a broader application of KD in clinical practice with collaboration of neurologists and dietitians. Key words: children, ketogenic diet, ketone bodies, medium-chain triglycerides, epilepsy