Whooping cough remains an urgent health problem to date, despite a fairly good study of the pathogen, epidemiological features, clinical manifestations, as well as the development of effective means of specific prevention.

Objective: to assess the epidemiological situation of whooping cough in the Orenburg region in 2023, identify risk groups, formulate prevention directions.

Materials and methods: the analysis of the incidence of whooping cough was carried out on the basis of statistical reporting data, a retrospective analysis of 126 outpatient records with a diagnosis of whooping cough was carried out, according to the data of the referral to polyclinic.

Results: in 2023, there was a significant increase in the incidence of pertussis infection in all age groups. The risk group for high morbidity was children aged 15—17 years, with a history of vaccinated against whooping cough.

Conclusion: monitoring of vaccination and revaccination in young children, the alertness of practical doctors in the diagnosis of whooping cough in adolescents and adults will reduce the incidence of whooping cough and prevent adverse outcomes. 

Тhe characteristics of the humoral immune response to SARS-CoV-2 in children, particularly those with comorbid conditions, remain incompletely understood. The observed variability in antibody production and the sensitivity of serological assays complicate the objective assessment of seroconversion in the pediatric population.

Objective: To determine the qualitative and quantitative profiles of IgM and IgG antibodies against SARS-CoV-2 in children with somatic comorbidities during the acute phase of COVID-19 amid the circulation of the Omicron variant.

Materials and Methods: A prospective, single-center, non-randomized cohort study was conducted involving hospitalized children with confirmed COVID-19 and underlying chronic conditions. Serological testing was performed on days 1, 8, and 14 of illness using enzyme-linked immunosorbent assay (ELISA) and immunochemiluminescence assay (ICLA) to measure IgM and IgG levels.

Results: A total of 99 children with comorbidities were included in the analysis. The seropositivity rate for IgM remained low at all time points (up to 26.3% on day 14). IgG antibodies were detected in the majority of patients as early as day 1, with ELISA demonstrating higher sensitivity (77.6%) compared to ICLA (60%), peak IgG levels were observed on day 8, followed by a significant decline by day 14 (p < 0.01). Children with respiratory system diseases exhibited statistically higher IgG levels compared to those with hemoblastoses, solid tumors, primary immunodeficiencies, and nervous system disorders.

Conclusions: Serological diagnosis of COVID-19 in children with comorbidities requires careful consideration of the testing method, disease timeline, and type of underlying somatic pathology. IgG antibodies serve as a more informative marker than IgM, with ELISA offering superior sensitivity. 

The goal is to improve the prediction of HIV infection course in children and the dynamics of immunocompetent cells activation markers, taking into account comorbid pathology.

Research methods. We examined 91 children who were 1—4 months old at the time of HIV infection diagnosis (Me 3 months, ICI 1—4.5 months) there was a subclinical stage (41) or a stage of secondary diseases (50).

Results. In patients at the stage of secondary diseases, in addition to HIV-associated symptoms, opportunistic infections of bacterial, viral and fungal etiology developed. These children were more often diagnosed with comorbid pathology (100% and 85.4%; p = 0.0067). In this group, a higher HIV blood viral load, a low number of CD4+ lymphocytes and other significant disorders in the immune system were detected. These patients showed increased expression of the immunocompetent cell activation marker (HLA-DR), the apoptosis readiness receptor (CD95), as well as the number of cells at the stage of early (AnV+) and late apoptosis (AnV+/Pr+). When analyzing the frequency of various comorbid pathologies in a multivariate mathematical logistic regression model, it was found that an independent predictor of HIV infection rapid progression in children was the presence of active form of congenital infection (OR 4.8; 95% CI 1.1—24.7; p = 0,0233).

Conclusion. In 55% of children, rapid progression of HIV infection occurs. The reasons for the unfavorable course of the disease are active replication of HIV and the development of immune status profound disorders, including hyperactivation and apoptosis of immunocompetent cells. An independent predictor of disease rapid progression is the presence of an active form of congenital infection, and therefore early diagnosis and treatment are necessary. 

Objective: to study the clinical and laboratory features of community-acquired pneumonia in children in the pre-pandemic period of COVID-19 to improve the differential diagnosis of respiratory tract lesions.

Materials and methods. A retrospective analysis of 266 medical records of patients treated at the Children's City Clinical Hospital No. 9 named after G.N. Speransky of the Health Department of Moscow in 2019 with a referral diagnosis of community-acquired pneumonia was carried out. To verify the diagnosis of pneumonia, chest X-ray was used.

Results. Community-acquired pneumonia was clinically similar to acute and obstructive bronchitis and other respiratory diseases, which creates objective difficulties in diagnosis without the use of laboratory and instrumental studies

Objective: to analyze the causes and clinical course of lymphadenitis in children and adolescents for timely detection of cases of malignant lymphadenopathy.

Materials and Methods: A clinical observational study of 268 patients diagnosed with lymphadenitis was conducted between January 2019 and December 2023.

Results: Lymphadenitis was the most frequent (56.5%) form of lymphadenopathy of unspecified cause at the time of the first medical examination. The structure was composed of: infectious diseases, including tuberculosis lesions (30.6%), herpesviral infections (5.6%), cat scratch disease (1.9%), urogenital (1.9%), dental and otorhinolangiologic pathologies (1.9%). Lymphadenitis of unspecified etiology accounted for 56.0% of cases in which symptoms regressed on empirical therapy. Isolated tuberculous lesions of peripheral lymph nodes were rare (1.1%). The median age was 8.0 (5;12) years, lymphadenopathy was detected more often in children 4—11 years old, the ratio of boys:girls was 1:1.4. The time from symptom onset to treatment was 5 days. Cervical and inguinal lymph nodes were most often affected (48.3%), dense or dense-elastic (89.1%) and painful (87.3%), the median size of lymph nodes was 2.0 (1.3; 3.0) centimeters. According to the ultrasound data, the lymph nodes was most often marked by decreased echogenicity (88,9%), heterogeneous echo structure (71,9%), with increased or normal blood flow (100,0%), presence of preserved lymph nodes capsule. Antibacterial therapy was administered to the majority of patients (83.3%). No improvement was observed in 27 patients (17.4% of patients receiving antibiotic therapy) who received repeated courses. 

Among other children infectious diseases hemolytic-uremic syndrome (HUS) remains a significant issue since it can lead to death or chronic kidney pathology. The most vulnerable group are children under the age of 5. The progression of HUS triggered by bacterial intestinal infections is more likely to occur as a sporadic disease in the summer-autumn period.

Materials and methods. The article describes clinical observations of patients undergoing treatment at the children infectious hospital at the Budgetary Healthcare Institution of Omsk Oblast City Clinical Hospital №1 named after A.N. Kabanov in Omsk. In each case the development of HUS was preceded by symptoms of acute intestinal infections of medium severity. Сlinical and laboratory manifestations matched the classic version of HUS development. When conducting bacteriological research of stool, causative agents of intestinal infections were not identified. Only in two cases etiological agent was identified using PCR. 

Objective: to study and analyze the clinical and epidemiological situation on the incidence of parasitic invasions in preschool children in the Astrakhan region.

Materials and methods. The research was conducted at the Department of Infectious Diseases and Epidemiology of Astrakhan State Medical University, on the basis of the epidemiological department of the Federal Budgetary Institution of Health «Center for Hygiene and Epidemiology in the Astrakhan Region».

Results. 17.8% (884 people) of protozoan cases were detected, of which the majority were lamblia — 96.8% (856 people); in rare cases, amoebas were recorded — 2.5% (22 people) and in isolated cases — blastocysts — 0.7% (6 people). The structure of helminthiasis incidence in children is completely different, with a total of 82.2% (4,098 people) of cases identified, including enterobiasis — 99.1% (4,066 people), ascariasis — 0.7% (30 people), toxocariasis — 0.1% (4 people), trichuriasis and diphyllobothriasis — 0.02% each (1 person each).

Conclusions. Enterobiasis was detected in most cases in preschool children, with infection rate being 99.1%. The structure of protozoan morbidity among preschool children, compared to helminthiasis, is several times smaller and amounts to 17.8%, of which giardiasis was most frequently identified (96.8%). The most common patient complaints were lack of appetite, restless sleep, loose stools, nausea, and weakness. 

The relevance of the problem of congenital toxoplasmosis is due to the prevalence of toxoplasmosis in the world, the severity of congenital toxoplasmosis and the possible development of residual changes in the central nervous system, sensory organs and other internal organs.

The aim of the work is to summarize the data available in the literature on the etiology, epidemiology, clinical picture, diagnostics, treatment and prevention of congenital toxoplasmosis.

Materials and methods. A review of domestic and foreign literature over the past 25 years was conducted, including Internet resources, including search engines PubMed, Cochrane Library, Google Scholar.

Conclusion. To prevent congenital toxoplasmosis, it is possible to screen both those planning pregnancy and pregnant women. In case of confirmed infection of pregnant women, the attending physician may consider drug prophylaxis, which in the Russian Federation can be carried out using the macrolide drug spiramycin. One of the areas of prevention is the development of vaccines, among which vaccines based on nanoparticles seem to be especially promising. 

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is rare type of hypersensitivity that could lead to multiple organ dysfunction syndrome. First line of treatment is fast causal drug identification and its withdrawal and systemic glucocorticoids. A clinical case of a DRESS-syndrome in 16-years-old adolescent with rush, fever, lymphadenopathy and hepatitis manifested in response to doxycycline usage for acne treatment is presented. To diagnosis, the patient was validated according to the three most used criteria systems: Bocquet H. et al., European Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) and Japanese consensus group («J-Scar»).

The purpose of this clinical observation was to familiarize readers with this rare complication, the criteria systems used in its diagnosis. 

Objective: to demonstrate a clinical case of fulminant COVID-19 in a teenager without comorbid pathology. The article presents a clinical case of a fulminant course of a new coronavirus infection in a 16-year-old teenager with the development of multiple organ failure (bilateral polysegmental pneumonia, grade 2 respiratory failure, cardiovascular and renal-hepatic insufficiency). The emphasis is placed on heart damage with the development of acute myocardial damage, which is confirmed by high levels of troponin I and pericarditis.

Conclusion: the described clinical case demonstrates the development of multiple organ failure and death in an initially healthy child. The development of acute myocardial injury is shown.

Objective: to demonstrate a clinical case of fulminant COVID-19 in a teenager without comorbid pathology. The article presents a clinical case of a fulminant course of a new coronavirus infection in a 16-year-old teenager with the development of multiple organ failure (bilateral polysegmental pneumonia, grade 2 respiratory failure, cardiovascular and renal-hepatic insufficiency). The emphasis is placed on heart damage with the development of acute myocardial damage, which is confirmed by high levels of troponin I and pericarditis.

Conclusion: the described clinical case demonstrates the development of multiple organ failure and death in an initially healthy child. The development of acute myocardial injury is shown.

Fungal infections of the skin, due to their variety of clinical presentations, often cause difficulty in making a diagnosis. Majocca's granuloma (GM) is a rare form of fungal skin infection that is caused by dermatophytes in over 95% of cases. Long-term superficial dermatophyte, systemic or local immunosuppression, and disruption of the integrity of the skin barrier are risk factors for developing Majocca granulomas. Improper treatment with topical glucocorticosteroids and antibiotics can worsen the condition. We present the case of a ten-year-old immunocompetent boy who developed Majocca granulema after mechanical skin injury. Late diagnosis and incorrect treatment tactics using local glucocorticosteroids at the prehospital stage probably led to the progression of manifestations in the primary focus and further dissemination of the pathogen, with the development of folliculitis and skin lesions. Due to low sensitivity of GM laboratory tests, even after skin microscopy using potassium hydroxide (KOH) and genome-wide double sequencing, no etiological agent could be identified in our patient. The patient was discharged from hospital with clinical improvement after taking systemic antifungal drugs. Against the background of a break in treatment and a violation of the care recommendations, the patient developed a recurrence of the disease, which was prevented by long-term administration of terbinafine. 

Pregnant women and newborn infants are at risk of developing severe listeriosis infection. The time of development and the character of the clinical picture of neonatal listeriosis depend on the timing and mechanism of infection of the foetus. Intrauterine infection with this pathogen is one of the leading factors in the development of sepsis and meningitis in the neonatal period. Early laboratory diagnosis and prompt administration of antibiotic therapy are crucial to improve prognosis and reduce mortality in children.

The aim of the work is to demonstrate the tactics of management of a premature infant with severe course of early neonatal listeriosis and favourable outcome according to the results of catamnestic observation.

Materials and methods: The medical records of a child who was under inpatient treatment in a children's multidisciplinary hospital in January—February 2025 due to laboratory-confirmed neonatal disseminated listeriosis were analysed; the outcome of this patient was assessed based on the result of a second planned hospitalisation in April 2025; the world medical literature on neonatal listeriosis was studied using search engines and databases elibrary, PubMed, Google Scholar, Scopus.