Analysis of absolute lymphocyte count in patients with COVID-19

https://doi.org/10.1016/j.ajem.2021.02.054Get rights and content

Highlights

  • Absolute lymphocyte count may help identify patients who are unlikely to have COVID-19.

  • Lymphopenia can be used as a marker of disease severity in patients with COVID-19.

  • Lymphopenia may serve as a prognostic indicator in patients with COVID-19.

  • Absolute lymphocyte count may help cohort patients who are unlikely to have COVID-19.

Abstract

Introduction

Symptoms of COVID-19 vary in severity and presentation. When admitting patients to the hospital, it is desirable to isolate patients with COVID-19 from those without the disease. However, reliably identifying patients with COVID-19 in the emergency department before hospital admission is often limited by the speed and availability of testing. Previous studies determined a low lymphocyte count is commonly found in patients with COVID-19. We sought to explore the sensitivity of absolute lymphocyte count in patients presenting to the emergency department requiring subsequent hospitalization who were found to have COVID-19.

Methods

A retrospective chart review was performed on 312 patients with laboratory-confirmed COVID-19 who were admitted to the hospital from the emergency department. The absolute lymphocyte count for these patients was used to calculate sensitivities at various cut-off values. The relationships between absolute lymphocyte count and variables, including age, sex, need for intubation, and mortality, were also explored.

Results

Cut-off values for absolute lymphocyte count ranged from 1.1 K/uL to 2.0 K/uL, with sensitivities of 72% and 94%, respectively. Additionally, lower mean absolute lymphocyte counts were identified in males, patients who required intubation, and patients who died.

Conclusion

Knowing the sensitivity of absolute lymphocyte count in patients with COVID-19 may help identify patients who are unlikely to have the disease. Additionally, absolute lymphocyte count can be used as a marker of disease severity in patients with COVID-19.

Keywords

COVID-19
Coronavirus
Absolute lymphocyte count
Lymphopenia

Abbreviations

SARS-CoV-2
severe acute respiratory syndrome coronavirus 2
COVID-19
coronavirus disease
ED
emergency department
ALC
absolute lymphocyte count
RT-PCR
reverse transcription-polymerase chain reaction
CBC
complete blood count
WBC
white blood count
CDC
Centers for Disease Control and Prevention
AGPs
aerosol-generating procedures

Cited by (0)

1

Present address: Department of Anesthesiology, Division of Critical Care, University of California, San Diego, San Diego, CA, USA.

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