The article reviews the literature on community-acquired pneumonia. Own results of study on the features of clinical, laboratory, and instrumental manifestations of community-acquired pneumonia during epidemic of the new coronavirus infection of COVID-19 are given.

The article presents literature data on changes in labo­ratory parameters in new coronavirus infection COVID-19 and the results of our own researches. It was found that in the first three days after hospitalization, most patients had normocytosis, a normal number of lymphocytes. In the mild form, there were slightly more people with normal or with an increased number of leukocytes, granulocytes, but in moderate course, leukopenia, lymphopenia, granulocytosis and granulocytopenia, thrombocytosis, thrombocytopenia were registered more often. At the same time, in the mild form, there were more patients with an increased number of band neutrophils. In mild course, there were no individuals with an increased number of band neutrophils after 3 days in the hospital. Leukocytosis, lymphopenia, granulocytosis were no longer detected after 6 days in the hospital; during this period, the number of patients with leukopenia, thrombocytopenia also decreased significantly, most people had normocytosis. In patients with moderate-to-severe course, leukocytosis and leukopenia were observed for a longer period than with the mild course, even after 10 days in hospital. Most patients had normocytosis. By the sixth day of hospital stay, there were more individuals with granulocytosis (no such patients were registered at a later date), with an increased number of band neutrophils. After 6 days, there was greater number of patients with lymphocytosis, thrombocytosis and lymphocytopenia.

The article provides a review of the literature on the dynamics of blood counts in patients with the new coronavirus di­sease 19 and provides data from our own researches. It was found that patients of all age groups on the background of fluoroquinolone and dexamethasone treatment demonstrated an increase in leukocyte count, and in people over 60 years of age, its increase to the highest levels was observed. Individuals under 60 compared to patients over 60 years who received only antibiotics with the inclusion of fluoroquinolones, without the use of dexamethasone, had a slightly lower level of lymphocytes (р > 0.05) at the beginning of hospitalization, but already from day 4 their growth was observed. At the same time, in people over 60 years old, on the contrary, indicators decreased. In patients under 60 years of age who received antibiotics with the inclusion of fluoroquinolones and 16 mg of dexamethasone during treatment, their gra­dual increase with normalization was observed; this did not happen when 8 mg were used. In patients over 60 years of age who received antibiotics with the inclusion of fluoroquinolones, 8 and 16 mg dexamethasone and who recovered, fluctuations were observed at reduced numbers with a slight tendency towards normalization, as it was observed in younger people. In patients over 60 who received antibiotics without the use of dexamethasone and died, there was a decrease in lymphocyte level during treatment. In people over 60 who recovered, greater fluctuations in the level of lymphocytes to normal values were observed when using 8 mg of dexamethasone, while against the background of 16 mg of dexamethasone, the former showed a decrease in their level with a tendency to increase. At the same time, those who died, on the contrary, had a more significant decrease without a tendency towards normalization. Among patients under 60 and over 60 who have recovered, the former have a more rapid decrease in the le­vel of granulocytes with a tendency to normalize. In people under 60 years of age, when 16 mg of dexamethasone were prescribed, a slightly faster decrease in granulocyte level was observed. Also, a tendency to a more rapid decrease in the level of granulocytes was observed in patients older than 60 years against the background of the use of 16 mg of dexamethasone. In the age group over 60 years old against the background of 16 mg of dexamethasone, those who recovered demonstrated a decrease in granulocytes, and those who died, on the contrary, their increase. In people older than 60 years who recovered, when using 8 mg of dexamethasone and antibiotics with the inclusion of fluoroquinolones in the treatment regimen, the level of band neutrophils was slightly higher than in people younger than 60 years, and a period of its normalization was longer. Against the background of 16 mg of dexamethasone, people over 60 years of age who recovered, had lower indicators of band neutrophils in the first three days and a longer period of their normalization compared to those under 60 years of age. Patients over 60 years old who died, in comparison with those who reco­vered, already from the beginning of hospitalization demonstrated higher levels of band neutrophils and their gradual increase, while those who recovered, on the contrary, had a decrease. In patients under 60 years of age who, in addition to antibiotics, received 8 mg of dexamethasone, in the first three days after hospitalization the level of C-reactive protein (CRP) was lower than in people over 60 years of age who recovered. In both groups of patients, a tendency towards a decrease in the level of CRP was observed. Recovered patients over 60 years of age who received fluoroquinolones and 16 mg of dexamethasone had hig­her CRP content in the first three days than younger patients, and almost the same rates as those who died at the age of 60 years and older. Patients over 60 years old and those who recovered against the background of the use of 16 mg dexamethasone, had a more rapid decrease in the level of CRP; at the same time, in those who died, its slower decrease was observed. Also, the dynamics of ala­nine aminotransferase, aspartate aminotransferase, urea, creatinine, glucose, creatine phosphokinase, lactate dehydrogenase was established depending on the doses of hormones, age and the consequences of the disease course.

The article provides a review of the literature on the effectiveness of glucocorticoids in viral infections, including the new coronavirus infection COVID-19. The results of our research of the dynamics of laboratory parameters in patients who recovered and those who died are presented. The average age of patients who received 8 mg of dexamethasone and recovered was less than that of the deceased. The average day on which the patients were hospitalized in the ICU and who received 8 mg of dexamethasone in both groups was the same (on average on day 7). It is noteworthy that in patients who recovered, the febrile temperature was more often recorded before hospitalization, while in those who died it was more often subfebrile. The temperature during hospitalization in all categories of patients was on average at subfebrile numbers. The respiratory rate on admission in all categories of patients did not differ significantly and on average was about 19/min (up to 20/min was in 50 % of patients who recovered and 58.3 % of those who died). Those who recovered were more likely to have a normal heart rate on admission, but tachycardia was less common than within those who died. In patients who subsequently died, lower saturation levels were more often recorded upon admission. In the first 3 days after hospitalization, in patients who recovered and received 8 mg of dexamethasone, leukocytosis and granulocytosis were recorded more often; there was an increased number of stab neutrophils and the number of patients with it. The patients who subsequently died more often developed leukopenia, more pronounced lymphopenia with an increased quantity of patients with it; they presented more pronounced thrombocytopenia (the number of patients with it did not differ from those who recovered), higher erythrocyte sedation rate. In patients who subsequently died, during the observation period, there was a gradual increase in the number of leukocytes, but a gradual decrease in the number of lymphocytes, the creatine phosphokinase level increased from the 7th–9th days of hospitalization; on days 4–6 of hospitalization, the lactate dehydrogenase level significantly increased with its subsequent decline to a level that was greater than this in patients who recovered. Initially. The patients who recovered had an increase in leukocytes with their subsequent gradual decrease, a gradual increase in the level of lymphocytes, a decrease in the level of creatine phosphokinase, lactate dehydrogenase. In all categories of patients, a gradual decrease in the number of stab neutrophils was observed over time, a gradual increase in the number of platelets was also observed over time, but in those who recovered their level was slightly higher; in both groups, an increase in the urea level was observed over time, but in those who died its level from day 7 and later was significantly higher than in those who recovered; in patients in both groups, an increase in the level of creatinine was observed over time, but in those who died, its level from day 7 and later was significantly higher than in those who recovered; both groups showed a decrease in C-reactive protein over time, but those who died from the very beginning of their hospital stay and during all follow-up periods had higher levels than those who recovered.

This article provides a review of the literature on the symptoms, laboratory blood values of critically ill patients who recovered and those who died of the new coronavirus disease COVID-19. Physicians should consider the following when predicting the course of the disease: in the first 3 days after admission, patients who recovered were slightly more likely to have leukocytosis and leukopenia, normal and increased lymphocyte counts; there were more individuals with increased number of band neutrophils, and patients who subsequently died were more likely to have normocytosis, granulocytosis, lymphopenia, thrombocytopenia, and higher erythrocyte sedimentation rate. The evaluation of laboratory indices in dynamics is of great importance for the prognosis: patients who recovered, on day 4–6 had a less pronounced growth of leukocytes and subsequently, on the contrary, their reduction; on day 4–6 of hospital stay, there was a decrease in the number of lymphocytes with subsequent growth; high creatine phosphokinase values at the beginning of hospitalization decreased significantly from day 7–9 to reference values; from the time of hospitalization, there was a decrease in lactate dehydrogenase content; the average prothrombin index tended to decrease, but within normal limits. Patients who died later, already from day 4–6 had an increase in leukocyte count, a decrease in lymphocyte level; thrombocytopenia was registered more often, which persisted with time and decreased significantly, especially after 9 days; in all periods of observation, erythrocyte sedimentation rate was higher (median of 30–40 mm/h); from day 7, there were significant fluctuations in maximum creatine phosphokinase values with their significant increase; at the beginning of hospitalization, these patients had higher lactate dehydrogenase levels compared to the first group and maintained their advantages during all periods of observation with significant fluctuations of maximal values; when comparing these patients by observation periods, there were slight fluctuations in the prothrombin index, which most often registered in about 80 % of patients with a subsequent increase after day 9, but within normal limits; also, at the beginning of hospitalization, there were significant fluctuations in the minimum prothrombin index towards very low rates.