The aim of the study was to study the clinical and laboratory features of acute respiratory viral infections in hospitalized children.
The analysis of medical records of 623 patients admitted to the clinic, aged from 1 month to 16 years 11 months 29 days, was carried out. All patients were diagnosed with ARVI on the basis of clinical symptoms with laboratory confirmation in the study of naso- or oropharyngeal smears by PCR.
Three groups of children were identified: with respiratory syncytial (RSV) — 384 children (61,6%), metapneumovirus — 142 (22,8%) and bocavirus — 97 (15,6%) infections. It has been established that in the general structure of acute respiratory viral infections in hospitalized children, RSV and rhinovirus are the leading pathogens — 28,8—48,6% and 22,1—41,3%, respectively, depending on the calendar year. The main clinical form was acute bronchitis in 80,5% of cases of confirmed infection, with RS-viral etiology in 79,5% (n = 287) of cases, with metapneumo- and bocavirus infections in 85,6% (n = 95) and 77,8% (n = 56) of children, respectively. Bronchiolitis was characteristic of RSV infection in 10,5% of cases (n = 38). From 10 to 19,4% of cases, the course of these viral infections was complicated by the development of pneumonia.

Herpesviruses are the most common etiological agents of encephalitis in children. The most pathogenic properties for humans are: Herpes Simplex virus type 1, type 2, Varicella Zoster virus, Human Herpes virus type 6 and Epstein-Barr virus, combined infection with which, along with the individual characteristics of the patient's immune status, can lead to a severe course and unpredictable outcome encephalitis.
Materials and methods. Clinical and neurological monitoring, etiological verification of infectious agents in the blood and cerebrospinal fluid by PCR and ELISA methods were carried out in 85 children with encephalitis at the age of 10—18 years. In patients suffering from herpesvirus encephalitis, the levels of pro-inflammatory cytokines, interleukins, chemokines were determined in the blood during the acute period of the disease and after 10—14 days.
Results. A decrease in the production of IFN-α and IFN-γ was revealed, which is an unfavorable factor prolonging the course of an active herpes virus infection. Conclusions. Cytokines should be considered as one of the prognostic factors for the course and outcomes of encephalitis in children, which will allow timely correction of patient management tactics in each specific case and improve the outcome of the disease.

The purpose of the study is to improve the diagnosis and prognosis of opportunistic infections in children infected with HIV by vertical and parenteral routes, taking into account the dynamics of clinical and immunological parameters.
Research methods. Clinical and laboratory examinations were carried out in 192 children infected with HIV by the vertical route (91; group I), parenteral route in infancy (44; group II) and over the age of one year (57; group III).
Research results. In group I, a rapid development of immunosuppression was observed: mild immunodeficiency was diagnosed at the age of Me 4 (IQI 2—10) months, advanced immunodeficiency — Me 11 ( IQI 6—24.5) months, severe immunodeficiency — Me 23 ( IQI 11— 56) months. Clinical manifestation of opportunistic infections occurred in the first three years of life with a relatively high content of CD4-lymphocytes. Localized bacterial infections (Me 27,5; IQI 21,9–34,1/100 MYO), candidiasis (Me 14,1; IQI 10,2—18,9 / 100 MYO) and generalized infections (Me 5,2; IQI 2,9—8,5 / 100 MYO) had the highest relative incidence rate. In group II, there was a slower progression of immunosuppression (within one to seven years), the addition of opportunistic infections with a lower content of CD4-lymphocytes, in terms of one to nine years, a high relative incidence of herpes simplex infection (Me 12,9; IQI 7,8—14,9 / 100 MYO), herpes zoster (Me 3; IQI 1,5—5,4 / 100 MYO) and pneumocystosis (Me 3,8; IQI 2,1—6,4 / 100 MYO). In group III, there was a slow progression of immunosuppression (within one to eight years), the development of opportunistic infections with a low content of CD4-lymphocytes, in terms of two to ten years, a rarer manifestation of most diseases.
Conclusion. These patterns should be taken into account when planning diagnostic, therapeutic and preventive measures in children with HIV infection, taking into account the path and age at the time of infection.

Materials and methods. The features of the course of pregnancy and childbirth, the condition of children at birth, histomorphological conclusions of placentas and the expression of the CD15 marker in the placentas of 40 children with congenital infectious diseases, 10 children with asphyxia at birth and 10 healthy full-term children were analyzed.
Results. The analysis showed the absence of reliable clinical and morphological criteria for the risk of developing a congenital infectious disease. Thus, the majority of mothers of children of all comparison groups had various somatic pathology: 33 (82.5%) in group 1, 8 (80%) in group 2, 6 (60%) in group 3 (p ≥ 0.05) Children of all comparison groups were statistically comparable in gestational age, anthropometric data and assessment on the Apgar scale. During histological examination, inflammatory changes in the afterbirth in children of the compared groups were recorded with almost the same frequency: in 17 (42.5%) children with intrauterine infection, 4 (40%) with asphyxia at birth and 2 (20%) healthy children (p ≥ 0.05). At the same time, immunohistochemically, placentas of children with congenital infectious diseases were characterized by a significantly higher level of CD15 expression compared to placentas of healthy children: CD15 expression coefficient in placentas of children with congenital infectious diseases was 6.9 ± 0.9, in the group of healthy children — 0.7 ± 0.5, (p < 0.05).
Conclusion. The use of the immunohistochemical marker CD15 makes it possible to predict congenital infectious disease in newborns in the absence of obvious morphological signs of an infectious lesion of the afterbirth, and can be used to form risk groups for the implementation of infectious pathology.

Рurpose: to identify clinical and laboratory criteria that mark the severity of infectious mononucleosis in children, with the identification of risk factors for the development of severe forms and unfavorable course.
Patients and methods. A comparative prospective clinical study involved 200 children aged 3 to 11 years with moderate (125 people) and severe (75 people) form of infectious mononucleosis. When comparing clinical and laboratory data in the compared groups, the Mann-Whitney test was used. For multiple comparisons, the Kruskal-Wally test was used. Significance of differences was determined at a significance level of 0.05 (p < 0.05).
Results. A comparative analysis of the clinical and laboratory manifestations of infectious mononucleosis revealed statistically significant differences in the studied parameters depending on the severity of the disease. Severe forms of infectious mononucleosis were distinguished by the most pronounced clinical symptoms, as well as changes in hematological parameters and biochemical changes. The combined etiology of infectious mononucleosis also contributed to a more severe course of the disease.
Сonclusion. Timely diagnosis and assessment of the severity of the manifest form of infectious mononucleosis determine the adequacy of the appointment of rational antiviral and pathogenetic therapy, preventing the development of adverse effects and complications.

The aim is to establish the effect of the persistence of the Epstein-Barr virus on the morphofunctional state of the gastric mucosa in chronic gastritis in children.
Methods. 324 children aged 6—16 years with chronic gastritis were examined. We analyzed clinical and anamnestic data, the results of esophagogastroduodenoscopy with biopsy, genetic typing of Hp with the identification of pathogenicity genes VacA, CagA, IceA, BabA. The persistence of the Epstein-Barr virus was determined by the detection of its DNA in the materials of gastrobiopsy. The titer of class G antibodies to gastric parietal cells was studied in 110 patients.
The results of the study. In children with chronic gastritis, Epstein-Barr virus was detected in the gastric mucosa in 49.1% of cases. In these patients, its colonization by highly pathogenic Hp strains was detected 1.8 times more often than in patients who had no infection with this virus. The persistence of the Epstein-Barr virus contributed to an increase in the severity of inflammation, the appearance of signs of indefinite atrophy of the mucous membrane and in the absolute majority of children was not accompanied by an increase in the titer of antibodies to the parietal cells of the stomach.
Conclusion. The persistence of Epstein-Barr virus in the gastric mucosa in chronic Hp-associated gastritis contributes to its infection with highly pathogenic Hp strains and severe inflammation. No data have been obtained indicating the role of Epstein-Barr virus in the formation of atrophic or autoimmune gastritis in childhood.

The paper analyzes approaches to etiotropic therapy and structural assessment of the range of drugs for the treatment of campylobacteriosis in children. The methods of content analysis, grouping, data aggregation, comparative and marketing analysis were used. The information base of the study was the State Register of Medicines, federal clinical guidelines for the provision of medical care to children with campylobacteriosis, European and American clinical guidelines, as well as instructions for the medical use of drugs.
Comparative analysis showed that Russian clinical guidelines contain 15 international non-proprietary names used for the etiotropic therapy of campylobacteriosis. The analysis carried out by drug producing countries shows that the leading positions in the supply structure are occupied by Russian producers (68.26%). Structuring by dosage forms makes it possible to single out tablet positions (47.46%). At the same time, 36.47% of the range of drugs are approved for use from the age of 12, which limits the implementation of modern approaches to the rational etiotropic therapy of campylobacteriosis in pediatrics. Structural analysis of the range of pharmaceutical substances identifies a significant contribution to the structure of imports of Chinese producers (46.30%), which, in turn, justifies the prospects for import substitution. Solving the problem of improving the quality of medical care for children with campylobacteriosis determines the prospects for further research based on the principles of evidence-based medicine using the tools of mathematical-statistical and pharmacoeconomic analyses.

The urgency of the problem of human cysticercosis is due to the widespread prevalence of this disease, polymorphism and the severity of clinical manifestations.
The purpose and result of the work is to summarize the available information about the etiology, epidemiology, clinical picture, diagnosis, and treatment of human cysticercosis.
Conclusion. Cysticercosis affects several million people worldwide. The clinic depends on the location of the cysticercus. Diagnostics is carried out on the basis of a morphological study of the obtained biomaterial, instrumental, serological and molecular genetic research methods. Albendazole, praziquantel are used as etiotropic therapy. Surgical removal of cysticercus is performed according to indications.

Multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19 is a rare life-threatening immunopathological complication of COVID-19 that develops 1-6 weeks after the acute coronavirus infection. MIS-C is characterized by fever and multiorgan inflammation.
We present a clinical case of a 10-year-old boy with skin lesions at the onset of MIS-C (erythematous malar rash, lacelike rash on the trunk and extremities and petechiae) with macrophage activation syndrome development and the early stage of primary Epstein-Barr virus infection (EBV infection) which required the exclusion of X-linked lymphoproliferative disease.
This clinical case demonstrates the complexity of diagnosis in MIS-C with skin manifestations at the onset of the disease, especially with concurrent activation of other infections, particularly EBV infection.

The article presents a clinical case of reactivation of chronic Epstein-Barr viral (EBV) infection complicated by the development of hepatitis in a 15-year-old teenager with COVID-19, which is of interest to infectious disease practitioners, pediatricians and other specialists in terms of the clinical course and differential diagnosis of these two viral diseases.
It is shown that the reactivation of EBV against the background of the current new coronavirus infection COVID-19, accompanied by an increase in the level of aminotransferases in the blood, leads to a more severe course and prolonged stay of the patient in the hospital, as well as the appointment of additional drug therapy with subsequent rehabilitation measures.

HIV infection and HCV infection are still serious and widespread infections that lead to high morbidity and mortality of the population worldwide.
The aim is to assess the risks of perinatal transmission of HIV/HCV co-infection and the choice of modern treatment tactics in children.
Аnalyzed data in foreign and domestic literature. A clinical case of perinatal transmission of HIV/HCV co-infection is described.
Results. Тhe features of perinatal transmission of infection depending on its variants (mono-HIV infection, hepatitis C and co-infection with HIV/HCV) and risk factors are shown. A clinical example demonstrates the implementation of perinatal transmission of HIV/HCV co-infection in the presence of major risk factors. The improvement of therapeutic tactics in a child with co-infection is shown.
Conclusion: in the described clinical case, numerous risk factors for perinatal transmission of HIV/HCV co-infection are demonstrated, the presence of which led to the realization of co-infection in a child. The effectiveness of modern tactics for the treatment of HIV infection and chronic viral hepatitis C has been demonstrated.

Kidney disease and chronic renal failure are among the main comorbidities of the complicated course of COVID-19.
Objective: to identify the clinical features of the course of a new coronavirus SARS-CoV-2-infection in a child aged 2 years 2 months with chronic kidney disease and dialysis-dependent renal failure.
A new coronavirus infection typically began with a moderate intoxication syndrome and catarrhal symptoms, confirmed by the detection of SARS-CoV-2 RNA. Computed tomography of the chest revealed signs of bilateral pneumonia, 30% damage to the lung tissue. Progression occurred by the 4th day of hospitalization with the development of a multisystem inflammatory syndrome, including damage to the cardiovascular system of the digestive system against the background of the existing end-stage renal failure. Laboratory criteria for multisystem inflammatory syndrome were an increase procalcitonin, C-reactive protein, and ferritin. As a result of the developed multiple organ failure, a fatal outcome occurred.