Leukocytosis and alteration of hemoglobin level in patients with severe COVID‐19: Association of leukocytosis with mortality

Dear Editors The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for coronavirus disease 2019 (COVID-19). The clinical characteristics of COVID-19 pandemic announced by the World Health Organization (WHO) in March 2020 may be presented by a severe form of pneumonia in some patients (10%-15%) which might progress toward acute respiratory distress syndrome, multi-organ failure and death. The clinical laboratory provides important information related to the COVID-19 diagnosis, prognosis, and response to therapy. In severely affected patients with COVID-19, leukocytosis was more prevalent as it was observed in11.4% severe COVID-19 patients compared to 4.8% in patients with mild to moderate disease. For the first time we report white blood cells (WBCs) count and hemoglobin (Hb) level among patients with severe COVID-19 from Iran (Table 1). The Farabi Hospital of Kermanshah University of Medical Sciences, Kermanshah, Iran as the second referral center of COVID-19 in Kermanshah Province, with a population around 2 000 000, started the admission of COVID-19 patients from March 7, 2020. A total number of 3574 individuals referred to the emergency unit of this hospital from March 7 to May 12, 2020 that among them 537 individuals were hospitalized due to COVID-19 infection according to the chest CT scan and/or real time polymerase chain reaction. Seventy-four severely affected patients (44 males and 30 females) were admitted to the intensive care unit (ICU) of the hospital. The mean age of all ICU admitted patients was 65.1 ± 17.1 years (23-90 years), with the mean age of 61.4 ± 18.5 years (23-90 years) in men and the mean age of 70.5 ± 13.2 years (39-89 years) in women (Table 1). Among all severely affected patients the mean WBCs count was 9.1 ± 4.9×10/L (8.9 ± 4.9 × 10/L in males and 9.4 ± 5 × 10/L in females). In survivors the WBCs count was 7.6 ± 3.5 × 10/L compared to 10.5 ± 5.6 × 10/L (P = .008) in non-survivors. Comparing survivors with non-survivors indicated among non-survivors 16 out of 39 patients (41%) had WBCs count upper normal range (>11 × 10/L). However, only 4 out of 35 (11.4%) survived patients had WBCs count more than 11 × 10/L (χ = 8.2, P = .004, OR = 1.16 (CI 1.03-1.3, P = .015). Also, the WBCs count was 10.5 ± 6 × 10/L in patients required intubation compared to 8.3 ± 4.1 × 10/L (P = .098) in those patients did not require intubation. Furthermore, higher WBCs count was detected in patients with comorbidities (hypertension, diabetes mellitus, coronary artery disease, cancer, renal transplantation, chronic obstructive pulmonary disease, and osteomyelitis) than those without comorbidities (9.5 ± 4.9 vs 8.2 ± 4.8 × 10/L, P = 0.27; Table 1). There were seven patients with leukopenia (1-3.8 × 10/L) that four of them (57.1%) died. The mean level of Hb was 140.2 ± 24.3 g/L (75-205 g/L) in all patients. In men the mean level of Hb was 143.1 ± 23.5 g/L (75-205 g/L) and in women was 136.1 ± 25.3 g/L (98-200 g/L). The mean Hb level in 35 survived patients was 139.3 ± 22.9, and in 39 non-survived patients was 141.1 ± 25.8 g/L (P = .75). There were 51 patients (68.9%) with comorbidities and the mean Hb level of 141.4 ± 26.4 g/L compared to 23 patients (31.1%) without comorbidities and the Hb level 137.6 ± 19.3 g/L (P = .49). Among patients 26 out of 74 (35.1%) required tracheal intubation with the mean Hb level 137.3 ± 23 g/L compared to the mean level of 141.8 ± 25.1 g/L in 48 patients who did not require intubation (P = .44; Received: 10 June 2020 Revised: 1 August 2020 Accepted: 18 August 2020


Dear Editors
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for coronavirus disease 2019 (COVID-19). The clinical characteristics of COVID-19 pandemic announced by the World Health Organization (WHO) in March 2020 1 may be presented by a severe form of pneumonia in some patients (10%-15%) which might progress toward acute respiratory distress syndrome, multi-organ failure and death. 2 The clinical laboratory provides important information related to the COVID-19 diagnosis, prognosis, and response to therapy. 3 In severely affected patients with COVID-19, leukocytosis was more prevalent as it was observed in11.4% severe COVID-19 patients compared to 4.8% in patients with mild to moderate disease. 3 For the first time we report white blood cells (WBCs) count and hemoglobin (Hb) level among patients with severe COVID-19 from Among all severely affected patients the mean WBCs count was 9.1 ± 4.9×10 9 /L (8.9 ± 4.9 × 10 9 /L in males and 9.4 ± 5 × 10 9 /L in females). In survivors the WBCs count was 7.6 ± 3.5 × 10 9 /L compared to 10.5 ± 5.6 × 10 9 /L (P = .008) in non-survivors. Comparing survivors with non-survivors indicated among non-survivors 16 out of 39 patients (41%) had WBCs count upper normal range (>11 × 10 9 /L).
In summary, our study indicated a significant association between leukocytosis and the rate of mortality in patients with COVID-19.
Also, our findings indicated the higher rate of mortality among COVID-19 patients with higher Hb level. However, lower Hb level was detected in patients required tracheal intubation that its mechanism needs to be elucidated.

CONFLICT OF INTEREST
The authors declare they have no conflict of interest. Zohreh Rahimi (corresponding author) had full access to all of the data in this study and takes complete responsibility for the integrity of the data and the accuracy of the data analysis.

DATA AVAILABILITY STATEMENT
The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

ETHICS STATEMENT
Although our study was an observational study, verbal consent was obtained from patients or from the next-of-kin.