The problem of the clinical course and principles of treatment of the new coronovirus infection Covid-19 has been the most discussed for two years. The disease can occur as an asymptomatic carriage, latent course, and severe forms with damage to the lungs, cardiovascular, circulatory and nervous systems, urogenital and gastrointestinal tracts.  Numerous studies of Covid-19 have made it possible to study in detail the pathogenesis and apply effective methods of treatment using monoclonal antibodies to cytokines and their receptors, Janus-kinase inhibitors, convalescent plasma, etc. At the same time, reliable prognostic criteria that determine the characteristics of the course and the outcome of the disease has not been established. The features of the clinical course of a new coronavirus infection in patients with rare comorbid pathology (genetic diseases, a history of organ and tissue transplantation, paraneoplastic processes) are also of scientific and practical interest. With this in mind, the article presents clinical cases of a new coronavirus infection Covid-19 in identical twins.Patients A. and С., 39 years old, were admitted to the Regional Clinical Infectious Diseases Hospital with complaints of fever up to 37.5-37.80C, dry cough, shortness of breath at rest, weakness. Both patients fell ill at the same time, on the fourth day after contact with their father, who was diagnosed with Covid-19 coronavirus infection, confirmed by a PCR test. Upon admission, the patients were clinically diagnosed with Covid-19 coronavirus infection, a confirmed moderate form. Bilateral polysegmental pneumonia of moderate severity. Respiratory failure I degree.Despite the same history data, the course of Covid-19 coronavirus infection in identical twins was significantly different. Patient A. had lymphocytosis up to 46% in the blood, ESR acceleration up to 12 mm/h, CRP increase up to 5 mg/ml, ferritin up to 333 ng/ml, interleukin-6 up to 7.5 pg/ml, D-dimer up to 560 ng/ml. Unlike patient A., his twin brother (patient C.) had lymphopenia up to 16%, accelerated ESR up to 20 mm/h, a significant increase in CRP up to 10 mg/mg, interleukin-6 up to 9.5 pg/ml , D-dimer - up to 750 ng/ml Patient A.'s condition remained stable. Against the background of the ongoing treatment, already on the fourth day of treatment, a pronounced positive trend was noted, on the 13th day of treatment, the patient was discharged from the hospital in a satisfactory condition under the supervision of a doctor at the place of residence.The condition of the patient С. on the 3rd day of hospitalization deteriorated sharply. Considering the decrease in SpO2 level to 88%, the lesion of the lung parenchyma is more than 70%, the council of doctors decided to conduct non-invasive oxygen therapy, the patient, in addition to the treatment, was prescribed antibacterial drugs, a drug of monoclonal antibodies to interleukin-6 and a selective reversible an inhibitor of Janus-kinases 1 and 2. On the 16th day of treatment, a CT scan of the chest organs was performed in dynamics, where a decrease in lung damage was noted, and a positive trend was also noted in laboratory parameters. Subjectively, the patient showed an improvement in well-being. During the next two days, the patient's condition with pronounced positive dynamics on the 19th day of hospital stay, the patient was discharged for rehabilitation at the place of residence.Thus, significant differences in the severity of the course of a new coronavirus infection in identical twins with the same history, the absence of aggravating comorbid conditions, are most likely due to the initial dose of the viral load, which was an important factor determining the development and course of infection.

The new coronavirus infection poses a particular threat to patients receiving immunosuppressive therapy, including those with a history of organ transplantation. The article provides a clinical observation of coronavirus infection in a kidney transplant recipient. Patient M., 61 years old, was admitted to the infectious diseases department of the Kursk City Clinical Hospital No. 4 with complaints of high fever, cough, shortness of breath, severe weakness, loss of appetite. When examining a swab from the nose and throat by PCR for SARS-Cov-2 RNA, a positive result was obtained. Based on the clinical picture, computed tomography of the lungs, positive PCR result for SARS-Cov-2 RNA, the diagnosis was made: Coronavirus infection Covid-19 confirmed, moderate form. Bilateral polysegmental pneumonia of moderate severity. RF - 0-I degree (CT-1). Bilateral nephrosclerosis. Condition after kidney transplant (2006). On the fifth day, the patient's condition worsened, which was combined with the progression of lung damage according to CT of the chest to 45% (CT-2), the appearance of signs of acute respiratory distress syndrome. Taking into account the severity of the patient's condition, a consultation was held with a transplantologist and a decision was made to correct immunosuppressive therapy with temporary withdrawal of cyclosporine. Over the next two days, the patient's condition remained stably grave. Subsequently, against the background of complex therapy, including glucocorticosteroids, antibacterial drugs, monoclonal antibodies to the interleukin-6 receptor, positive dynamics was noted in the form of a decrease in shortness of breath, cough, normalization of body temperature, and an increase in SpO2 up to 95%. This was combined with the restoration of disturbed laboratory parameters and the positive dynamics of the inflammatory process in the lungs according to CT scans. The treatment of kidney transplant recipients with Covid-19 has a number of features due to a pronounced suppression of the immune system against the background of immunosuppressive therapy and, as a result, the development of a severe infection, often with impaired graft function. At the same time, despite the severity of the course of the infectious process, the complete abolition of immunosuppressive therapy is not carried out, but its correction is carried out in the form of the exclusion of one of the drugs and a decrease in the dose of other immunosuppressants. Coronavirus infection in patients with a history of organ transplantation justifies the need for timely hospitalization and correction of immunosuppressive therapy to prevent a severe course of the disease and adverse outcomes.

Аtopic dermatitis is considered a multifactorial disease, with immune disfunction playing the main role in the development and chronic course of the disease. The aim of this study was the assessment of the functional activity of neutrophils and the peculiarities of the cytokine profile in patients with uncomplicated and complicated forms of atopic dermatitis. Materials and methods . All patients with atopic dermatitis were divided into two groups: the first group included patients with an uncomplicated form of atopic dermatitis, and the second group included patients whose disease was complicated by secondary pyoderma. The functional activity of neutrophils was studied using the chemiluminescence method, the quantitative content of α-defensins and cytokines in the peripheral blood by the ELISA method. Results. Comparison of the functional activity of neutrophils revealed a decrease in their chemiluminescence in patients with complicated pyoderma form of the disease in relation to uncomplicated form of atopic dermatitis. The production of alpha-defensins was significantly increased in both variants of the disease, but was 1.5 times lower in the complicated form. The level of IL-4, one of the cytokines that determine the development and course of allergic inflammation, exceeded on average 2.5 times the indicators of donors, the content of IL-2, a key cytokine of adaptive immunity, was 2 times lower than the control values, which indicates a lack of adaptive immunity in these patients. Similar changes were found in the IFN-gamma indices, the level of which was 1.4 times lower than normal in both forms of the disease. Conclusions. Thus, in patients with complicated and uncomplicated forms of AD, significant differences were revealed in the functional activity of neutrophils, production of α-defensins and cytokine profile, more pronounced in patients with complicated pyoderma form of the disease. Determination of the level of α-defensins (HNP 1-3), IL-2 and TNF-alfa can serve as a prognostic criterion for the severity of the course of blood pressure and a personalized approach to treatment.