Document Type : Research articles


1 PhD in Virology, Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran. Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.

2 MD, Infectious Diseases, Antimicrobial Research Center, Iran University of Medical Sciences, Tehran, Iran

3 MD, Department of Radiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.

4 MD, Infectious Diseases, Department of Infectious Diseases, School of Medicine, Iran University of Medical Sciences, Tehran, Iran

5 MD, Infectious Diseases, Department of Infectious Diseases, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Tropical Medicine Research Center, Iran University of Medical Sciences, Tehran, Iran

6 MD, School of Medicine, Iran University of Medical Sciences, Tehran, Iran

7 MSc in Microbiology, Department of Virology, Pasteur Institute of Iran, Tehran, Iran


Background: As COVID-19 severity and related death is a challenging issue, the protective effect and predictive value of lymphocyte count are critical. The present study investigated the importance of lymphopenia on disease severity and death rate.
Methods: This retrospective cross-sectional study was performed from April 2020 to June 2020 on a total of 300 patients with confirmed COVID-19 who attended the Firoozgar Hospital affiliated with the Iran University of Medical Sciences, Tehran, Iran. All of the COVID-19 patients referred to the hospital during the study period and met the inclusion criteria were enrolled and divided into two groups of lymphopenia (lymphocyte count less than 1.0x109/L) (n=138) and non-lymphopenia (n=162). All patient data from the medical records were acquired and utilized for statistical analysis.
Results: Of 300 patients 63.3% were male and 72% had underlying disease. The most common symptoms were dyspnea (50%), cough (41%), and lethargy (40%). Lymphopenia was associated with male gender (P=0.01). Additionally, mean age (P=0.02), ventilator need (P=0.03), and death (P=0.05) were significantly associated with lymphopenia compared to the non-lymphopenia group. The Lymphopenia group had lower levels of O2 saturation (P=0.04), AST (P=0.001), and ALT levels (P=0.02). Based on the chest CT scan results, there was a significant relationship between lymphopenia and the extent of pulmonary involvement (P=0.004)
Conclusion: Lymphopenia could clinically predict the severity of COVID-19. Lymphopenia was associated with male gender, older age, ventilator need, and death. Lymphopenia status had a significant relationship with reduced levels of O2 saturation, AST, ALT, and the extent of pulmonary involvement.


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