Platelets, leukocytes and their ratio as predictors of outcomes in patients with COVID-19

ABSTRACT

Background. Identification of easily accessible and most accurate predictors of favorable and fatal outcomes in COVID-19 is of great importance, as it allows timely correction of the patient’s treatment tactics. Objective: to develop predictors based on a general blood test that allow to predict COVID-19 outcome at relatively early stages. Patients/Methods. We examined 125 patients with severe and extremely severe course of COVID-19, in whom the number of platelets, leukocytes, their fractions and ratios were determined on days 1, 5, 7, 10, 14 and 21 of hospital stay. ROC-analysis was performed to calculate survival and lethality thresholds having predictive value. Results. It was found that the most accurate predictive parameters of COVID-19 outcome were leukocyte total number and ratios platelets/leukocytes, platelets/neutrophils, neutrophils/lymphocytes, neutrophils/monocytes. At the same time neutrophils/lymphocytes ratio can be considered the most accurate test for predicting COVID-19 outcome, that according to the expert scale with a “good” rating already at days 5 and 7, and with an “excellent” rating at days 10, 14 and 21 allow to conclude about the possible outcome of the pathological process. However, clinically valuable is the coincidence of predic-tions of COVID-19 outcome for 2–3 or more parameters. Conclusions. Neutrophils/lymphocytes ratio is the most accurate predictor of COVID-19 outcome. Total leukocyte count and platelet/leukocyte, platelet/neutrophil, neutrophil/lymphocyte, and neutrophil/ monocyte ratios are additional predictors of COVID-19 outcome. Timely correction of the identified shifts in the content of platelets, leukocytes and their fractions, as well as their ratios, seems to be a perspective direction in the pathogenetic therapy of COVID-19. © 2022, Hemostasis and Rheology LLC.