Background. AKI is one of the COVID-19 complications with high prognostic significance. In our research, we studied the prognostic role of several biomarkers that could help us understand AKI pathogenesis in patients with COVID-19. Methods. We evaluated the medical data of 500 patients hospitalized with COVID-19 in Tareev Clinic from 5 October 2020 to 1 March 2022. The diagnosis of COVID-19 was confirmed with positive RNA PCR in nasopharyngeal swabs and/or typical radiological findings on CT scans. Kidney function was assessed in accordance with KDIGO criteria. In the selected 89 patients, we evaluated serum levels of angiopoetin-1, KIM-1, MAC, and neutrophil elastase 2 and their prognostic significance. Results. The incidence of AKI in our study was 38%. The main risk factors for kidney injury were male sex, cardiovascular diseases, and chronic kidney disease. High serum angiopoetin-1 levels and a decrease in blood lymphocyte count and fibrinogen level also increased the risk of AKI. Conclusions. AKI is an independent risk factor for death in patients with COVID-19. We propose the prognostic model of AKI development, which includes the combination of serum levels of angiopoetin-1 and KIM-1 on admission. Our model can help to prevent AKI development in patients with coronavirus disease.

Aim. In a retrospective study, we evaluated factors associated with the early development of septic shock in patients with severe COVID-19. Materials and methods. We collected medical records of the intensive care unit patients submitted by the local COVID-19 hospitals across Russia to the Federal Center for the Critical Care at the Sechenov First Moscow State Medical University (Sechenov University). Septic shock in crticially ill patients requiring mechanical ventilation was defined as a need in vasopressors to maintain blood pressure. Results. We studied 1078 patients with severe COVID-19 who were admitted to the intensive care units for respiratory support. There were 611 males and 467 females. The mean age was 61.013.7 years. Five hundred twenty five medical records (48.7%) were received from the Moscow hospitals, 159 (14.7%) from the Moscow region, and 394 (36.5%) from the hospitals located in 58 regions of the Russian Federation. In 613 (56.9%) patients, diagnosis of SARS-CoV-2 infection was confirmed by PCR, and in the other cases it was established on the basis of the clinical picture and the results of the chest CT scan. Septic shock developed in 214 (19.9%) of 1078 patients. In the logistic regression model, the risk of septic shock in patients older than 50 years was higher than in patients of a younger age (OR 2.34; 95% CI 1.533.67; p0.0001). In patients with more severe SARS-CoV-2 infection, there was an increase in the prevalence of cardiovascular diseases, including coronary heart disease and atrial fibrillation, type 2 diabetes and malignant tumors. The risk of septic shock in patients with three or more concomitant diseases was higher than in patients without any concomitant chronic diseases (OR 1.76; 95% CI 1.762.70). Conclusion. The risk of septic shock in patients with acute respiratory distress syndrome induced by SARS-CoV-2 is higher in patients older than 50 years with concomitant diseases, although a severe course of the disease is also possible in younger patients without any concomitant disorders.

Aim. To determine the incidence and risk factors of acute kidney injury (AKI) in Russian cohort of patients with COVID-19. Materials and methods. We included 315 patients, who were hospitalized with COVID-19 from October 2020 till February 2021. The diagnosis was established on the basis of the positive SARS-CoV-2 swab test and/or typical radiologic findings on CT scans. Results. AKI complicated the clinical course in 92 (29.21%) cases. The independent risk factors of AKI were female sex, underline chronic kidney disease and the highest level of C-reactive protein during hospitalization. In the general group of patients were 41 (13%) lethal cases, in the group with AKI 32 (34.8%). Compared with those without AKI, patients with AKI had 4.065 (95% confidence interval 2.154 to 7.671) times the odds of death. Respiratory support, the highest serum creatinine and glucose levels appeared to be the risk factors of death among patients with AKI in the multivariable Cox regression. Conclusion. The clinical course of COVID-19 was complicated by AKI in 29% cases. The independent risk factors of AKI in patients with COVID-19 are underline chronic kidney disease, circulatory disorder and the highest level of C-reactive protein during hospitalization.

Aim. To study demographic, clinical, serological and morphological features of interstitial pneumonia with autoimmune features (IPAF), compare survival in IPAF and interstitial lung disease in connective tissue diseases (CTD-ILD), and identify predictors of mortality and transformation to CTD in the IPAF group. Materials and methods. The IPAF group included 48 patients (75.0% women, median age 57.5 years), CTD-ILD 49 patients (79.6% women, median age 60.0 years). The analysis of demographic, clinical, laboratory and instrumental data was performed, as well as comparison of survival with the KaplanMeier method and the log-rank test in the IPAF and CTD-ILD groups. In the IPAF group, predictors of mortality and the development of CTD were studied with multivariate regression analysis. Results. Duration of observation period did not differ significantly in the IPAF and CTD-ILD groups (40.0 and 37.0 months, respectively). Clinical criteria of IPAF were observed in 25 (52.1%) patients, serological in 44 (91.7%), morphological in 44 (91.7%). Mortality in the IPAF group was significantly higher than in the CTD-ILD group (29.2 and 6.1%, respectively; p=0.023). The presence of diabetes mellitus, CT-pattern of usual interstitial pneumonia, and an initial low forced vital capacity value were independent predictors of mortality in the IPAF group. During the observation period, the development of CTD was noted in 4 (8.3%) patients with IPAF. The independent predictor of the CTD development was the increased C-reactive protein level. Conclusion. IPAF is characterized by a lower survival rate compared to CTD-ILD, and a relatively low risk of CTD transformation.