Clinical laboratory and radiation parameters associated with different outcomes of severe new coronavirus infection (COVID­19) with pneumonia in patients receiving tocilizumab

Abstract

ntroduction. Coronavirus infection 2019 (COVID-19) is characterized by high morbidity and mortality. Interleu- kin-6 receptor inhibitors, including tocilizumab, are used for the anti-inflammatory therapy of COVID-19. The aim of the study was to compare the clinical, lab and radia- tion characteristics of surviving and deceased patients with severe COVID-19 and pneumonia caused by SARS- CoV-2 who received tocilizumab and identify features that were associated with various outcomes. Methods. The medical records of 31 hospitalized COVID-19 pa- tients were stu died. All patients received a single dose of tocilizumab 400 mg. Two groups were created. Group 1 included 17 patients who were discharged with improve- ment, Group 2–14 fatal cases. The methods of parametric and nonparametric statistics were used for processing. Results. The condition of patients from Group 2 more often than in Group 1 was assessed as severe already at admission, p=0.022. Only 4 patients from Group 1 and all patients from Group 2 were allocated to the intensive care unit; the mechanical ventilation was used exclusively in group 2, p <0.001. The groups differed in terms of the SpO2 le vel, p=0.023, and the concentration of C-reactive protein (CRP) at admission, p=0.047, as well as in the vo- lume of lung tissue damage, p=0.027. Tocilizumab was admi nistered to all patients within a comparable period from the onset of the disease. There was an increase in the neutrophil/lymphocyte ratio in peripheral blood (NLR) by the day of its administration in Group 2, p=0.026. The NLR le vel increased even more significantly within 5–7 days after administration, p=0.045 (p=0.007 compared to baseline). The NLR value in Group 2 changed insigni- ficantly. The blood ferritin level in patients from Group 1 by the day of tocilizumab administration was lower than in Group 2, p=0.014, and decreased after the treatment, p=0.01, in contrast to Group 2. The decrease in the CRP concentration after the appointment of tocilizumab in Group 1 was also significant, p=0.001. Conclusions. The deceased COVID-19 patients who received tocilizu- mab were characterized, compared with the survivors, by the initially more severe course of the disease, more pronounced hypoxemia, as well as the volume of lung tissue damage and laboratory abnormalities, inclu ding the le vels of NLR, CRP and ferritin. Monitoring of these in- dicators appears to be necessary to assess the course of COVID-19 and make a decision on the anti-inflammatory therapy with tocilizumab.