PREDICTORS OF MORTALITY IN HOSPITALIZED COVID-19 PATIENTS

When treating patients with COVID-19, prognostic and diagnostic tests to assess the risk of severe disease and adverse outcome are particularly important. The analysis of demographic, clinical, laboratory and instrumental data obtained on ICU admission was performed on a sample of 109 patients to determine potential predictors of lethal outcome. The factors increasing the risk of adverse outcome included age =57 years (AUC = 0.777, P < 0.001), hypertension (RR = 3.073, P = 0.033), ARDS (RR = 17.455, P < 0.001), advanced chest CT severity score (HR = 1.569, P = 0.039), severe and critical COVID-19 (RR = 6.964, P = 0.016), neutrophilia (AUC = 0.729, P = 0.005), lymphopenia (AUC = 0.705, P = 0.023), thrombocytopenia (AUC = 0.713, P = 0.018), reduced MCHC (AUC = 0.700, P = 0.026), elevated RDW (AUC = 0.718, P = 0.007), LDH (AUC = 0.891, P = 0.005) and D-dimer (AUC = 0.806, P = 0.029).

Naive T and B cells in COVID-19 patients

Introduction: COVID-19 patients with acute respiratory distress syndrome (ARDS) have an immune imbalance when systemic inflammation and dysfunction of circulating T and B cells lead to a more severe disease. TREC (T cell receptor excision circle) formed during maturation of naive T cells in the thymus and KREC (kappa-deletion recombination excision circle) developed during maturation of naive B cells in bone marrow. Using TREC/KREC analysis, we studied the level of naive T and B cells in peripheral blood of COVID-19 patients. Methods: TREC/KREC analysis was performed by multiplex real-time quantitative PCR on a DNA samples of peripheral blood. The total sample size was 36 patients from 18 to 45 years old;10 (27.78%) patients had ARDS, and 4 (11.11%) of them did not survive. Results: Patients with ARDS differed from the non-ARDS group ones in reduced lymphocyte count (p = 0.014), increased neutrophil count (p = 0.049), and neutrophil-to-lymphocyte ratio (NLR) (p = 0.002). During days 6 to 20 of hospitalization, a higher NLR was detected in ARDS patients compared with non-ARDS patients (Fig. 1A). Analysis of TREC/KREC levels both per 100,000 cells revealed significant differences: TREC/KREC values were lower in the group of ARDS patients;these differences persisted after adjustment for multiple comparisons (Fig. 1B). The TREC/KREC levels were also lower in non-survivors than in survivors. TREC/KREC negatively correlated with NLR;the highest correlation was recorded for TREC per 100,000 cells (Spearman's rho = - 0.726, p = 1.0 × 10E-06, coefficient of determination R2 = 0.527). Conclusions: Thus, TREC/KREC analysis is a potential prognostic marker for assessing the severity and outcome in COVID-19. (Table Presented).

Biomarkers of air-blood barrier damage in covid-19

The search for sensitive and specific markers enabling timely identification of patients with a life-threat-ening novel coronavirus infection (COVID-19) is important for a successful treatment. The aim of the study was to examine the association of molecular biomarkers of air-blood barrier damage, surfactant proteins SP-A and SP-D and Club cell protein CC16, with the outcome of patients with COVID-19. Materials and methods. A cohort of 109 patients diagnosed with COVID-19 was retrospectively divided into two groups. Group 1 comprised survivor patients discharged from the ICU (n=90). Group 2 included the patients who did not survive (n=19). Association of disease outcome and SP-A, SP-D, and CC16 levels in blood serum, clinical, and laboratory data were examined taking into account the day of illness at the time of bio-material collection. Results. The non-survivors had higher SP-A (from days 1 to 10 of symptoms onset) and lower CC16 (from days 11 to 20 of symptoms onset) levels vs survivors discharged from ICU. No significant differences in SP-D levels between the groups were found. Conclusion. According to the study results, the surfactant protein SP-A and Club cell protein CC16 are associated with increased COVID-19 mortality.

CLINICAL AND HISTOPATHOLOGICAL FEATURES OF LUNG IN JURY IN COVID-19 INFECTION

The aim of the study was to evaluate the histopathological changes in the lungs of patients who died of a new coronavirus infection (COVID-19) in relation to the length of hospital stay. We evaluated lung autopsy material, autopsy reports, and death summaries of 39 patients who died of COVID-19. The length of hospital stay ranged from a few hours to 25 days. At all stages of the disease, lung alterations (desquamation of bronchial and alveolar epithelium), circulatory disorders (alveolar edema and hemorrhages, congestion in small blood vessels, thrombosis), compensatory response (fibrosis) were identified. The patients who died during the first week of hospitalization demonstrated predominant signs of circulatory disorders (alveolar edema, hyaline membranes, alveolar hemorrhages, congestion in small blood vessels). Fibrosis, usually not typical for the first week of acute respiratory distress syndrome, was detected in 46% of the deceased during the first week of hospitalization, which may be due to late hospitalization or patterns of fibrosis development in COVID-19. For those who died in the 2nd and 3rd weeks of hospitalization, the compensatory response and progression of fibrosis were noted. By the 3rd week, pulmonary fibrosis was detected in 91% of patients. Thrombotic complications (thrombosis, pulmonary artery thromboembolism) were observed in almost half of fatalities occurring during weeks 2-3. Hemorrhagic infarction was found in 43% (6 patients) who died during week 2 of hospitalization, three of them were diagnosed with pulmonary embolism, indicating progression of pulmonary vascular damage.