Background. Lennox–Gastaut syndrome (LGS) is a classic developmental and epileptic encephalopathy with a debut in childhood, characterized by resistance to therapy, a severe course, and an unfavorable prognosis. Due to the existing difficulties in treatment of LGS, hopes are pinned on development of new antiepileptic drugs with fundamentally different mechanisms of action, aimed specifically at the treatment of this severe form of epilepsy.
Rufinamide (Inovelon®) is a new antiepileptic drug registered in the Russian Federation for use in the adjunctive therapy of LGS in patients older than 1 year. The main mechanism of action of rufinamide is the restriction of neuronal discharges associated with the blocking effect on sodium channels (regulation of sodium channels activity by increasing duration of their inactive state), and stabilization of neuronal membranes. The drug has a number of advantages concernung pharmacokinetic parameters and efficacy (including a wide spectrum of antiepileptic activity, good oral absorption, absence of active metabolites, urinary excretion, low affinity for plasma proteins, biotransformation without cytochrome P450 isoenzymes, low risk of drug interactions) and fairly good tolerability. The daily dose of rufinamide varies from 600 mg (with simultaneous administration of valproate) to 1000 mg (if the patient does not take valproate) in children over 4 years of age with a body weight of less than 30 kg and up to 2200–3200 mg in children over 4 years of age with a body weight of more than 30 kg and in adults; in children under 4 years of age, the maximum daily dose in combination with valproate is 30 mg/kg, and without valproic acid – 45 mg/kg.
Aim. To analyze the efficacy and tolerability of rufinamide in the treatment of epilepsy based on the long-term experience of using the drug in the Svt. Luka’s Association of Medical Institutions.
Materials and methods. We observed 64 patients aged from 1.5 to 26 years (44 men, 20 women) treated with rufinamide (Inovelon®). Among them, the structural etiology LGS was diagnosed in 36 patients, the genetic and presumably genetic etiology LGS – in 28. In all cases, rufinamide was used in accordance with approved indications as an additional antiepileptic drug, more often in combination with valproate, topiramate, levetiracetam or lamotrigine. Titration of the drug was carried out according to the recommendations in the instructions for use, up to a therapeutic dose that ranged from 200 to 1600 mg/day (in most cases from 400 to 1200 mg/day), depending on age and concomitant therapy.
Results and conclusion. Remission of all types of seizures was registered in 17 (26.6 %) patients, and a decrease in the incidence of seizures by more than 50 % was recorded in 28 (43.8 %) patients. Of them, 13 patients demonstrated reduction in seizures frequency by more than 75–90 % and remission of one of several types of seizures. In general, the therapeutic effect (reduction of seizures frequency by at least 50 %) was achieved in 45 (70.3 %) of 64 patients. A decrease in seizures frequency of by at least 50 % was observed in 8 (12.5 %) patients; in 10 (15.6 %) patients, rufinamide therapy was not effective; in 1 (1.56 %) case an aggravation of bilateral convulsive seizures was noted when rufinamide was administered.
In most cases, rufinamide is well tolerated. Our patients had side effects in 10 (15.6 %) cases. Only in 2 (3.1 %) cases, rufinamide was withdrawn directly due to side effects (the reason for withdrawal in these cases was an allergic reaction and psychosis).
The retention rate for therapy lasting 1 year or more is 65.6 % (42 of 64 patients).
Thus, our data have demonstrated efficacy and good tolerability of rufinamide in treating epileptic seizures associated with LGS, confirming numerous literature data. However, in our analysis, a higher rate of seizure remission was obtained, although we have included patients with mainly resistant forms of epilepsy in the analysis.

Background. Cerebral palsy is the most common cause of childhood disability among diseases of the nervous system, the prevalence of which averages 2.5 cases per 1,000 children.
Aim. To identify relevant indicators in relation to the prediction of delayed rates of neuropsychic development in children and the formation of cerebral palsy in children 5–8 years old using mathematical modeling.
Materials and methods. The study included 100 patients aged 5–8 years: 79 patients with neurological disorders and deviations in psycho-speech development, 21 patients – comparison group. The examination of children in both groups included: analysis of the child’s life history, analysis of psychomotor development in the first year of life, analysis of morbidity in the first year of life, assessment of psychomotor development at the time of the study, electroneuromyography using stimulation and superficial electroneuromyography, as well as ultrasound examination of the lower leg muscles with assessment of the functional state and muscle density using fibroscan.
For statistical processing of the obtained data, descriptive statistics were performed. Determination of the statistical significance of indicators was carried out using the Kolmogorov–Smirnov test for continuously distributed values and Fisher’s exact test for discrete values. One-hot coding was used to represent categorical features. The analysis of the obtained data was carried out using a Python program using the pandas, numpy, scikit-learn, and boruta libraries.
Results and conclusion. For children with deviations in neuropsychic development, significant early diagnostic markers are parameters of psychomotor development and neurological status (age when the child began to hold his head, decreased strength of the flexors of the foot and hip, level of walking) and instrumental examination (ultrasound of muscles thighs, electroneuromyography) – changes in the density and parameters of electrical excitability of muscles, which can serve as an early diagnostic sign of the development of motor dysfunction and an indicator for the formation of a trajectory of rehabilitation therapy.

Despite significant advances made in epileptology, treatment-resistant epilepsy accounts for approximately 30 % of all forms of this disease. Such diseases include, among others, Lennox–Gastaut syndrome – a classic developmental and epileptic encephalopathy with onset in childhood, characterized by resistance to therapy, severe course and poor prognosis. For patients in this category, the search for new effective antiepileptic drugs remains highly relevant, especially in cases where numerous combinations of antiepileptic drugs do not produce an effect, surgical treatment is impossible, and alternative methods (vagus nerve stimulation and ketogenic diet) are ineffective. The authors present a review of the literature on the modern definition and diagnostic criteria of Lennox–Gastaut syndrome, diagnostic methods and treatment of this form of epilepsy, which has a severe course and a generally unfavorable prognosis.

For more than two hundred years after its discovery, nitric oxide (I) has been widely used in medicine as an anesthetic, in the car industry as an engine performance enhancer, in the food industry as a preservative, and, unfortunately, among young people as a mild narcotic substance. Despite the widespread opinion that there is no harm from the use of “laughing gas” for recreational purposes, in the literature and in practice, there are a lot of cases when patients suffer from various complications, including neurological ones, caused precisely by the use of nitric oxide (I). One of the main mechanisms of the pathological effects of nitrous oxide on the nervous tissue is the inactivation of vitamin B12. This has been proven by studying the physicochemical properties of the gas, the effect on the organisms of laboratory animals, the change in the concentration of certain substances in the human body, and also by the use of cyanocobalamin for the treatment of these patients. This article describes a clinical case of the development of myelopolyneuropathy caused by the toxic effects of nitric oxide (I).

Hurst’s disease (acute hemorrhagic leukoencephalitis) is a rare fulminant demyelinating disease of the central nervous system. It was singled out as a separate nosological form in the middle of the 20th century. The etiology is not fully understood. According to statistics, the disease most often occurs after a viral or bacterial infection. Patients have an increase in body temperature up to febrile values, headaches, gastrointestinal disorders, cognitive impairments. When making a diagnosis, they are guided by the results of neuroimaging (computed tomography/magnetic resonance imaging), analysis of cerebrospinal fluid, and brain biopsy. Corticosteroids, acyclovir, antibiotics, immunoglobulins, plasmapheresis are used for treatment. The prognosis in patients with acute hemorrhagic leukoencephalitis is poor.

MERRF syndrome (myoclonic epilepsy ragged red fibres) belongs to the group of primary mitochondrial diseases and is characterized by a combination of myoclonic epilepsy and the phenomenon of ragged red fibres on muscle biopsy. The aim of this work is to study mitochondrial disorders in patients from a family with MERRF syndrome by determining the cytochemical activity of mitochondrial enzymes in peripheral blood lymphocytes and the level of lactate in the blood. Clinical cases of a 25-year-old sister and a 19-year-old brother with MERRF syndrome with the m.8344A>G variant in MT-TK (tRNA (Lys)) with a blood heteroplasmy level of 50 % in the sister and homoplasmy in the brother are presented. Mitochondrial disorders were assessed by blood lactate levels and cytochemical studies of mitochondrial enzyme activity in peripheral blood lymphocytes. Pre-prandial blood lactate levels were elevated in both patients. After a carbohydrate load, it increased in the sister, and decreased in the brother. The sister had decreased activity of peripheral blood lymphocyte enzymes while taking levetiracetam, 100 mg of coenzyme Q10 and 100 mg of L-carnitine. The dose of energotropic drugs was increased, which led to an increase in the activity of mitochondrial enzymes. The brother had a compensatory increase in the level of succinate dehydrogenase and a decrease in the activity of other enzymes. The methods we used can be used in clinical practice to diagnose mitochondrial disorders and to adjust the dosage of energotropic drugs, which remain relevant due to the lack of effective gene therapy.