Dynamic changes in routine blood parameters of a severe COVID-19 case.

backgroundNovel coronavirus infectious disease (COVID-19) has been spreading worldwide, and tracking laboratory indexes during the diagnosis and treatment of patients with severe COVID-19 can provide a reference for patients in other countries and regions.

methodsWe closely tracked the epidemiological history, diagnosis and treatment process, as well as dynamic changes in routine blood indicators, of a severe COVID-19 patient who was hospitalized for 26 days.

resultsOur study found that the patient's condition worsened in the first week after admission, white blood cells (WBCs), neutrophils, lymphocytes, monocytes, eosinophils, red blood cells (RBCs), hemoglobin, neutrophil lymphocyte ratio (NLR), platelets (PLT) and platelet lymphocyte ratio (PLR) decreased. On the 7th day of admission, the levels of these cells decreased to their lowest values, though the red blood cell distribution width (RDW) and C-reactive protein (CRP) level remained at high values. From 8 to 14 days of admission, the patient's condition improved, hypoxemia was corrected, and mechanical ventilation was discontinued. The number of WBCs, neutrophils, monocytes, eosinophils and lymphocytes increased gradually, and the erythrocyte parameters stopped declining and stabilized in a certain range; CRP decreased rapidly. On the 20th day of admission, the nucleic acid test was negative, WBC, neutrophil, CRP, NLR and PLR decreased gradually, and monocyte, lymphocyte, and eosinophil counts increased. Although RBCs and hemoglobin (Hb) levels continued to decrease, RDW gradually increased, indicating the recovery of hematopoiesis. In addition, it should be noted that monocytes and eosinophils were at extremely low levels within 10 days after admission; the recovery time of eosinophils was approximately 12 days after admission, which was earlier than other parameters, which might be of great value in judging the progress of the disease.

conclusionsDynamic changes in routine blood parameters might be helpful for the prognosis of COVID-19 patients and evaluation of the treatment effect.