The pathogenesis of inflammatory bowel diseases still remains unclear nowadays. Genetic disposition, impaired immune regulation, disturbance in intestinal microbiota composition, exposure to environmental factors are associated with the development of inflammation in intestinal mucosa and increased epithelial penetrance that define disease's development and progression. There is a theory in scientific literature that vitamin D deficiency (among other environmental factors) increases the risk of inflammatory bowel disease. However, the role of vitamin D in the development of gastrointestinal tract diseases remains poorly studied. This article presents current data on the vitamin D effect on the intestinal mucosa barrier function, on the immune system and on the intestinal microbiota in the context of inflammatory bowel diseases pathogenesis.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a primary electrical heart disease characterized by the development of polymorphic (including bidirectional) ventricular tachycardia in response to adrenergic stimulation. The leading clinical sign of CPVT is syncope provoked by physical or emotional stress, or adrenergic drugs administration. This disease is characterized by high mortality if not treated. The main treatment approach for CPVT is drug therapy with beta-blockers. Recently, however, there are more and more works stating that beta-blockers have lack of efficacy. Combination therapy with the antiarrhythmic drug of the IC class is one of the approaches before implementing the interventional treatment methods in several patients. Interventional methods include cardioverter defibrillator implantation and left side sympathectomy. This paper presents the modern view on the efficacy, safety, and indications for every management method for patients with CPVT.

Background. Despite the clear trend towards infant mortality decrease in our country, there are significant differences in values in some federal districts and regions of Russian Federation. Thus, the assessment of infant mortality rates and health indicators is crucial topic of scientific analysis. Objective. The aim of the study is to investigate selected child health indicators and infant mortality rates in the Chechen Republic. Methods. We have conducted the retrospective cross-sectional study of infant mortality rates, prematurity incidence, infant and newborn morbidity, and mortality of children born sick or got sick. The study was based on the data from official statistics and from the extraction of statistical reporting forms No. 12 and No. 32. Results. The Chechen Republic belongs to the regions with high infant mortality rate, however, it has decreased by 11.6% from 6.9 to 6.1‰ in 2018–2022. The major diseases causing lethal outcomes in infants in this region, and in Russia as a whole, were certain conditions that occur in the perinatal period, and congenital disorders. Meanwhile, mortality from respiratory diseases and some infectious and parasitic diseases exceeded the national average. Prematurity incidence in the republic was 1.5 times lower than the national average, newborns morbidity was 1.7 times lower, infants morbidity was 4.0 times lower. Trend analysis has revealed that prematurity incidence and newborns morbidity have slightly changed over 5 years (+2.2% and –1.0%), while infants morbidity had significant trend (–40.2%). All morbidity rates of children who died at the age under 1 year were significantly lower than the national average for all classes of diseases that are the most common for infants mortality. The mortality rates among children born sick or got sick were on average 5.4 times higher than similar indicators in Russia. The highest mortality rate was observed among children who died from perinatal conditions, congenital disorders, external causes, and some infectious and parasitic diseases. The level of the maternal and child health service performance was 0.44 on average over the 5-year interval, that corresponds to the average level of efficacy. Conclusion. This study has allowed to reveal that there is an urge to improve the organization of medical care for infants in the Chechen Republic.

Background. It was revealed in 2020 that immunization of children in decreed times in several subjects of Russian Federation was below the standard level. Therefore, monitoring of timely vaccination in children of these regions was relevant. Objective. The aim of the study is to evaluate changes in the timeliness of vaccination in children of two subjects of Russian Federation with low immunization rates according to 2020 data. Methods. Immunization of children born in 2015–2017 and 2020–2022 were studied according to the form of federal statistical monitoring (FFSM) No. 6 and vaccination record cards (form No. 063/y) obtained from children's polyclinics of the Republic of Bashkortostan (two in 2020 and three in 2023) and the Republic of Sakha (Yakutia) (two in 2020 and four in 2023). The vaccination timeliness among children against infections from the national immunization schedule (NIS) list was determined. The timeliness of vaccination was evaluated by the proportion of children who received the required number of vaccine doses against each of the infection from the NIS list by the decreed age among all persons of the decreed age. Results. Data from 998 records was analyzed. The increase in timely vaccination against all vaccine-controlled infections in children was revealed. The proportion of children vaccinated according to the NIS has increased by 1.5–4 times. Timely vaccination of 95% children in the decreed age (by FFSM No. 6) was achieved in the Republic of Sakha (Yakutia) against tuberculosis, hepatitis B, measles, rubella, and mumps, and in the Republic of Bashkortostan against measles, rubella, and mumps. The increase in the multivalent vaccines’ usage and simultaneous administration of several vaccines has been discovered. Conclusion. Monitoring the level of documented immunization and timely vaccination in children allows effectively control routine immunization quality. Implementation of multivalent vaccines and simultaneous administration of several vaccines in routine immunization provides radical change in the vaccination rate in pediatric population.

Background. Methylmalonic aciduria (MMA) is a rare disease from the group of hereditary metabolic diseases. The MMA clinical picture is polymorphic and meanwhile similar to other metabolic disorders. Determination of specific metabolites in biological fluids and molecular genetic testing are crucial to diagnose this disease. Timely diagnosis mainly determines the treatment efficacy and, therefore, the prognosis of MMA development. Clinical case description. Two siblings with MMA caused by methylmalonyl-CoA mutase deficiency (OMIM #251000) have shown duplication chr6-49459106-T-TA: NM_000255.4c.360dupT (p.Lys121fs) in homozygous state in exon 2 of the MMUT gene. The disease was diagnosed in the first child with underlying metabolic crisis that finally led to irreversible changes in organs and systems and lethal outcome. The diagnosis in the second child was established antenatally, thus, therapy was initiated from the first day of life. Favorable clinical course of the disease was observed during 5 months of follow-up. Conclusion. Timely MMA diagnosis (antenatal or during neonatal screening) is crucial for effective management and relatively favorable life prognosis for infants.

Wilson’s disease is severe autosomal recessive disease manifested primarily by hepatic, neurological, and psychiatric disorders due to excessive copper deposition in organs and tissues. Clinical case description. The variant with uncertain clinical value of the ATP7B gene, c.2111C>T (p.T704I, chr13:52534294G>A (HG19)), was described in the family where parents are cousins. The eldest daughter out of four children died at the age of 11 due to liver cirrhosis. Wilson’s disease was genetically confirmed in two children (clinically — abdominal form). The younger son was diagnosed heterozygous state of the disease (without any clinical manifestations). The revealed variant of the ATP7B gene was previously identified in 3 more patients with Wilson’s disease, however, in a compound heterozygous state with known pathogenic genetic variant. Conclusion. c.2111C>T (p.T704I) variant of the ATP7B gene can be considered as probably pathogenic. Further research is required to evaluate its functional significance in Wilson’s disease pathogenesis.

Background. Psoriasis and vitiligo are chronic, relatively common dermatological diseases. Meanwhile, their combination in children is rare. The combination of psoriasis and vitiligo in a child with Sotos syndrome has not been previously described. Clinical case description. The boy, 10 years old, was hospitalized with complaints (according to his mother) of rashes on the scalp, body, and limbs, with mild itching that was not related to the time of day. The pathological skin process was widespread. The patient was hyperactive, restless, emotionally labile, irritable. Complaints of rashes was mentioned firstly at the age of 7. Sotos syndrome was established at the age of 8 (variant c.6559C>T (p.Arg2187Ter) in 23 exon of the NSD1 gene (5q35.3), autosomal dominant type of inheritance (pathological allele de novo)). Psoriasis vulgaris was diagnosed with secondary vitiligo (localized form) at the age of 8.5 years. Symptomatic antipruritic and external pathogenetic therapy was performed in the hospital. Phototherapy was not prescribed due to the relative contradiction (small retrocerebral cyst) and the peculiarities of major disease (hyperactivity, restlessness) that complicated to place the child in the phototherapy booth. Positive dynamics was noted during the treatment (14 days): no itching, decrease of peeling severity, flattening and blanching of psoriatic rash elements to spots of post-inflammatory hypopigmentation. The lesion (focus of depigmentation) on the right knee joint skin remained unchanged. The patient was discharged to outpatient care. The prognosis for Sotos syndrome and skin lesions is favorable. Conclusion. The first medical observation of the child with Sotos syndrome burdened with psoriasis and vitiligo is presented. The pathogenetic correlation of these diseases is not clearly defined. Management of such cases requires the joint collaboration of dermatologists, geneticists and pediatricians.