The review presents 61 publications on the molecular mechanisms of pathogenicity, specific parameters of the infectious process and possibilities of laboratory diagnosis of coronaviruses, including SARS-CoV-2 - of the causative agent of COVID-19.

The objective of the study: to compare the degree of lung damage according to chest CT data to the clinical state of COVID-19 patient, to analyze the semiotics and changes in CT data.
Subjects and methods. 317 CT scans were retrospectively analyzed; those scans belonged to 98 patients with COVID-19 treated at N.V. Sklifosovsky Research Institute for Emergency Medicine. Patients were divided into 4 groups, depending on the degree of the lungs damage detected by CT during the primary examination, their clinical state was assessed at each subsequent CT scan. To determine the relationship between the degree of pulmonary changes and the clinical status of patients, a correlation analysis was performed using the rank correlation method, significance was
assessed using the Student's coefficient.
Results. It was found that CT allowed to identify changes in the lungs typical of COVID-19 and assess their degree, as well as to analyze progression or regression lung changes, including comparison with clinical data. A significant correlation was revealed (r_s = 0.577) between the growing degree of lung damage, as determined by CT and deterioration of the clinical status of patients.

The objective of the study: to identify the specific parameters of hepatotoxic reactions in tuberculosis patients depending on the presence of hepatitis B and C markers in the blood.
Subjects and methods. The state of the hepatobiliary system was studied in 107 HIV-negative patients with newly diagnosed infiltrative pulmonary tuberculosis in the destructive phase. The main group included 52 people with positive results of the tests for markers of viral hepatitis B and C, the comparison group included 55 people with negative results. The groups were compatible in age, volume of the lung tissue lesions, and drug resistance profile.
Results. Even before the start of anti-tuberculosis therapy, in the main group had elevated levels of cholinesterase and blood amylase, ultrasound examination detected hyperechoic liver parenchyma, enlarged right lobe of the liver, liver veins fibrosis, the enlarged diameter of the cystic duct and splenic vein, and splenomegaly (p <0.05), which was statistically significantly more frequent than in the comparison group. In the course of treatment, patients of both groups developed hepatotoxic reactions, however, in the main group they were more frequent versus the comparison group (88.4 and 21.8%, respectively, p <0.05), appeared earlier on average by 14 days and were accompanied by more pronounced clinical manifestations and abnormalities of biochemical parameters.

The objective: to evaluate the effectiveness of the medication containing a 7% NaCl solution and 0.1% sodium hyaluronate in patients with destructive pulmonary tuberculosis and multiple/extensive drug resistance (MDR/XDR) and inflammatory changes in the tracheobronchial tree.
Subjects and methods. A prospective randomized controlled study was carried out, which included 69 patients with destructive pulmonary tuberculosis and MDR/XDR and respiratory complaints and changes in the tracheobronchial tree detected by fibrobronchoscopy. All patients underwent a complete clinical and functional examination, and by analyzing the questionnaires, the mMRC dyspnea index was calculated, the CAT test was performed, and the response to treatment was assessed using the Likert scale. The patients were randomly divided into two groups. The main group included 30 patients; in addition to anti-tuberculosis therapy, through a nebulizer, they received inhalation with the solution containing 7% NaCl and 0.1% sodium hyaluronate, 5 ml 2 times a day for 10 consecutive days, 20 inhalations. The control group (39 people) received individual chemotherapy according to the resistance profile with standard mucolytic treatment. The examination was carried out before the course with the mucoactive drug (visit I), then at the end of the course – after 10 days (visit II) and after 30 days (visit III) from the moment of inclusion in the study. The significance of differences (p) was determined at p <0.05 using χ² Pearson, Fisher's exact test, Mann-Whitney test, and paired Wilcoxon test.
Results. There was an increase in the effectiveness of treatment of patients in this category according to the following criteria: disappearance or decrease of respiratory symptoms (on the 10th day from the start of treatment), early regression of inflammatory changes in the tracheobronchial tree (on the 30th day from the start of treatment in 24 (73.4%) patients in the main group, in 10 (25.1%) patients in the comparison group (RR = 3.34; 95% CI 2.78-3.90)].

The objective of the study: to assess the structure of extrapulmonary tuberculosis in two high-burden regions (Siberia, the Far East of the Russian Federation, and the Republic of Tajikistan), with the consideration of HIV status, gender, and age of patients.
Subjects and methods. A simple cohort open retrospective study was carried out based on the analysis of statistical reports from TB control institutions of the Republic of Tajikistan, Siberian and Far Eastern Federal Districts of the Russian Federation for 2018.
Results. In the Siberian Federal District and Far Eastern Federal District, among extrapulmonary forms of tuberculosis, the proportion of bone and joint tuberculosis made 43.6%, urinary tuberculosis – 21.3%, and tuberculosis of central nervous system ranked third and made 17%. In Tajikistan, bone and joint tuberculosis also prevailed and made 46.0%, followed by tuberculosis of peripheral lymph nodes. In Tajikistan, among extrapulmonary tuberculosis patients, HIV positive patients made only 3.5%, while in the Siberian and Far Eastern Federal Districts, they made 36.8%. However, in the Siberian and Far Eastern Federal Districts of the Russian Federation, among HIV positive patients with extrapulmonary tuberculosis, tuberculosis of the central nervous system (38.3%) prevailed, in the Republic of Tajikistan it was tuberculosis of peripheral lymph nodes (37.9%), followed by bone and joint tuberculosis (31.0%) and abdominal tuberculosis (17.2%). Urogenital tuberculosis was in the last place in the structure of extrapulmonary tuberculosis in HIV-positive patients.

To manage autonomic disorders in adolescents with tuberculosis, 100 people from 12 to 15 years old were examined and randomly divided into two groups: Group 1 received standard anti-tuberculosis therapy, and in Group 2, additionally to standard therapy, comprehensive treatment with Magne B₆ was used for 2 months, and then Valerian extract was used for another 2 months. For comparison, 50 healthy adolescents were examined. Before treatment, all adolescents with tuberculosis experienced a decrease in heart rate variability, a pronounced autonomic imbalance with the prevalence of sympathicotonia and overexertion of compensatory mechanisms. In Group 1, during the comprehensive treatment there were an increase in SDNN and Mo and decrease in AMo and tension index at rest. Active orthostatic test (AOT) was accompanied by a significant increase in SDNN, Mo and a decrease in AMo, which indicated an increase in the activity of the parasympathetic autonomic nervous system and decreased activity of the sympathetic autonomic nervous system. In the group receiving standard therapy, hypersympathycotonia persisted and manifested through significant (p < 0.05) reduction in such parameters as SDNN, increased heart rate, AMo, and Mo shift to short intervals. Medication management resulted in the vegetative balance by increasing heart rate variability, reducing hypersympathicotonia, improving the autonomic support of the cardiovascular system at rest and during AOT.

The objective: in the experiment, to study specific parameters of manifestations of hepatotoxic reactions to the combination of anti-tuberculosis drugs containing isoniazid and rifampicin in rats with different acetylation phenotypes.
Subjects and methods. Liver damage was modeled in rats, old females, belonging to the phenotype of rapid acetylation, and in mature males, belonging to the phenotype of slow acetylation, with a combination of basic anti-tuberculosis drugs, which were administered for 14 days. Hepatotoxic reactions were assessed by clinical observations of rats, biochemical parameters and morphological changes in the liver, which were compared with intact animals.
Results of the study: in female rats (fast acetylators of isoniazid), signs of the cytolytic mechanism of liver damage prevailed (more significant elevation of ALT activity, pronounced duration of thiopental sleep, pronounced hydropic degeneration of hepatocytes with the presence of hepatocyte necrosis, venous congestion and edema of the portal tracts). In males (with the phenotype of slow acetylation of isoniazid), a significant elevation of total and direct bilirubin levels, AST activity and, to a lesser extent, ALT were observed, i.e., signs of a mixed mechanism of liver damage (cholestatic and cytolytic).

The objective of the study: to perform the multivariate analysis of treatment outcomes in patients with multiple/extensive drug resistant tuberculosis (MDR/XDR TB), including those with HIV infection, whose chemotherapy regimens included bedaquiline.
Subjects and methods: 70 patients with MDR/XDR TB were enrolled in the retrospective two-center study, the multivariate analysis of treatment outcomes with bedaquiline-containing regimen was carried out.
Results: the performed multivariate analysis demonstrated high efficacy and good tolerability of bedaquiline-containing regimens for MDR/XDR TB treatment even despite the continuous ineffective treatment of patients in the past. The prolonged intake of bedaquiline for more than 24 weeks was not associated with a high level of adverse reactions. It was found that the use of cycloserine/terizidone made a significant contribution to the favorable outcome of chemotherapy. The factors associated with the most unfavorable treatment outcomes were the following: age above 60 years, concurrent chronic obstructive pulmonary disease, alcohol and/or drug addiction, and smoking.

The article describes a clinical case of Kaposi sarcoma in a patient with concurrent tuberculosis, HIV infection with severely compromised T-cell immunity, viral hepatitis B and C, and substances and alcohol abuse. Also, the patient had low adherence to treatment with anti-tuberculosis and antiretroviral drugs.