Introduction. Chronic urticaria (CU) in children remains a serious clinical problem, especially in cases of resistance to antihistamine therapy, indicating the involvement of non-histaminergic mechanisms, in particular the Substance P (SP) / neurokinin-1 receptor (NK-1R) axis. The chronic form of urticaria occurs in children under 15 years of age with a frequency of up to 1.1%, with the highest prevalence observed in the adolescent group, approaching that of the adult population.
Materials and methods. A non-systematic review of the literature was conducted. Publications were searched in PubMed, Google Scholar, CyberLeninka and eLibrary databases for the period 2000-2024 using the keywords: “substance P”, “chronic urticaria”, “children”, “neurogenic inflammation”, “NK-1 receptor”. 49 relevant sources were selected, including original studies, systematic reviews, clinical guidelines and case series. Due to the limited number of pediatric studies (n = 8), the data were extrapolated with caution, with the main focus on describing pathogenetic mechanisms and identifying gaps in the evidence base.
Results. SP has been shown to play a multifaceted role in the pathogenesis of CU in both adults and, presumably, children, acting as a mediator linking the nervous, immune and vascular systems. Via the NK-1R receptor, SP directly causes mast cell degranulation, mediates neurogenic inflammation, increases vascular permeability, has an immunomodulatory effect (chemotaxis of neutrophils and eosinophils, polarization of the Th2 response) and is a central link in stress-induced exacerbations. Elevated plasma levels of SP and NK-1R expression in the skin correlate with disease severity and resistance. At the same time, most studies have been performed on adult patients, while pediatric data are limited, which does not allow all mechanisms to be unequivocally extrapolated to the pediatric population.
Conclusions. The SP/NK-1R axis may be considered as one of the possible pathogenetic links in antihistamine-resistant CU in children. Despite the theoretical rationale for NK-1R blockade, NK-1R antagonists cannot currently be recommended for pediatric practice due to the lack of efficacy and safety data, as well as conflicting results in adults

Rationale. In pediatric practice, phenotypes of bronchial asthma (BA) defined by comorbid allergic diseases — atopic dermatitis (AtD) and allergic rhinitis (AR) — are of particular importance. Their combination in a single patient indicates a systemic nature of inflammation and likely a higher genetic predisposition. However, the contribution of heredity to the formation of different BA phenotypes in preschool children remains insufficiently studied.
Objective: to evaluate the frequency and structure of hereditary allergic history burden in different BA phenotypes in children under 5 years of age.
Materials and methods. A retrospective cohort study was conducted involving 493 children aged 3–5 years with BA and 200 control children. Four groups were formed based on phenotype: isolated BA (n = 128), BA with AtD (n = 130), BA with AR (n = 122), BA with AtD and AR (n = 113). Family history of allergy was analyzed with calculation of odds ratios (OR) and 95% confidence intervals (CI). The χ² test with Yates’ correction was used for frequency comparisons. Results. A positive hereditary history was found in 66,7% of children with BA compared to 19,5% in the control group (OR = 8,28; p < 0,001). The frequency of family history of allergy increased with the number of comorbid allergic diseases: isolated BA — 53.9% (OR = 4,83; p < 0,001), BA+AR — 55,7% (OR = 5,20; p < 0,001), BA+AtD — 70,8% (OR = 10,00; p < 0,001), BA+AtD+AR — 88,5% (OR = 31,76; p < 0,001). The BA+AtD+AR phenotype significantly exceeded other groups in the frequency of inheritance through both parental lines (31,0% vs. 5,5–13,1% in other phenotypes; p < 0,001 for all comparisons). The highest maternal inheritance rates were found in the BA+AtD phenotype (37,7%; OR = 5,16; p < 0,001), while the highest paternal inheritance rates were in BA+AtD+AR (25,7%; OR = 3,97; p < 0,001).
Conclusion. BA phenotypes in children under 5 years of age with multiple comorbid allergic pathologies, especially those including the combination of AtD and AR, have the most pronounced genetic determination. The greatest family history of allergy is characteristic of the BA+AtD+AR phenotype, confirming the role of accumulation of atopic diseases as a marker of high genetic predisposition.

Rationale: Allergic rhinitis is becoming an increasingly common disease, affecting a large proportion of the population, especially children. The steady increase in morbidity and the continuing difficulties of timely verification of the diagnosis dictate the need for an in-depth study of the epidemiological aspects of this pathology.
Objective: To assess the dynamics of the prevalence of symptoms of allergic rhinitis in schoolchildren of the Grodno region over a 15-year period (2008–2023) using the ISAAC questionnaire.
Materials and methods. The study, based on a survey of schoolchildren 6–7 years old and 13–14 years old, revealed an ambiguous dynamics of rhinitis symptoms. In younger students, there is an increase in sneezing and nasal congestion without signs of a cold, as well as an increase in cases of hay fever. Adolescents, by contrast, had decreased rates of rhinitis without infection, but increased rates of symptoms associated with allergic conjunctivitis and increased rates of established diagnosis of hay fever. The effect of symptoms on daily activity remains moderate or negligible in both age groups.
Conclusion. Improved diagnosis and awareness may contribute to the rise in diagnosed cases of allergic rhinitis. Further research is needed to identify the causes of the rise in allergic diseases and to develop prevention and treatment measures, including allergies and seasonal therapies.

Relevance. An urgent task of modern medicine is to assess the effectiveness of the immune response to hepatitis B vaccination in children with Down syndrome. Studies show that most children with Down syndrome do not develop sufficient levels of protective antibodies after standard hepatitis B vaccination. Assessing the effectiveness of the immune response will allow for the development of personalized vaccination programs for children with Down syndrome.
Objective: to assess the effectiveness of the immune response to hepatitis B vaccination in children with Down syndrome by studying the concentration of specific antibodies in their blood serum and comparing the results with their vaccination status.
Materials and methods. A cross-sectional cohort study was performed with the participation of 102 children with Down syndrome aged from 1 to 17 years. The concentration of IgG antibody titers to hepatitis B was analyzed, based on age and vaccination status (full, partial vaccination, no vaccination).
Results. 73 (71,6 %) children had completed hepatitis B vaccination among all the subjects. The concentration of hepatitis B antibodies in children with Down syndrome decreases significantly with age, reaching a titer below 10 mIU/ml in most adolescents over 12 years of age. In children with complete vaccination in the 1–5 years group, the geometric mean of antibody titers was 24.5 mIU/ml, in the 6–11 years group, it was 26.7 mIU/ml, while in children aged 12–17 years, the antibody titers were below the protective threshold, with a geometric mean of 2.13 mIU/ml, indicating the need for further revaccination under certain conditions. Correlation analysis revealed a negative relationship between age and antibody levels (r = −0.3205, p = 0.0057). Children with Down syndrome do not have an epidemiological advantage for hepatitis B in “indicator” groups
Conclusion. Among children with Down syndrome aged 12 years and older who have received a full course of hepatitis B vaccination, there is a very high percentage of those who do not have a p rotective antibody titer. It is recommended to develop a personalized approach to revaccination and monitor post-vaccination antibodies to maintain an adequate level of protection.

Relevance. According to some authors, the prevalence of Marshall syndrome in the pediatric population is unknown. The patients with PFAFA syndrome can be mistakenly follow up within the group of frequently ill children. The diagnosis is largely based on the knowledge of the main clinical symptoms of the disease, described by G. S. Marshall et al. (1987).
In the last time, hereditary autoinflammatory diseases are in the focus of research and practical interests of clinicians. The nature of the PFAFA syndrome is associated with cytokine dysfunction and dysregulation of the inflammasome, with allow it to be, classified as an autoinflammatory syndrome the disease is triggered by genetically determined dysregulation of congenital immunity associated with excessive production of inflammation mediators (IL-1, TNFα, IL-6, IL-12, etc.)
Material and methods. An analysis of the scientific medical literature on PFAFA syndrome (Marshall syndrome) and clinical case, of child with Marshall syndrome is presented.
Results. Our clinical example illustrates the problem of late diagnosis of PFAFA syndrome. In now time diagnosis of the disease is based on clinical criteria (periodiс fever, aphthous stomatitis, pharyngitis and cervical lymphadenitis) and new criteria are the necessary. The etiology and pathogenesis of the disease have not been definitive established