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Published on: March 22, 2022
Coronavirus disease 2019 and peripheral blood eosinophil counts: a retrospective study
Marjella Eijmael1, Nicky Janssens2, Saskia le Cessie3
1Department of Internal Medicine, Groene Hart Ziekenhuis, Bleulandweg 10, 2803 HH, Gouda, The Netherlands. m.eijmael@gmail.com.
Insights
Eosinopenia, a decrease in eosinophils, is common in COVID-19 patients. This study found that lower eosinophil counts correlate with increased COVID-19 severity, with severe cases showing the highest rates of eosinopenia.
Area of Science:
- Immunology
- Infectious Diseases
- Hematology
Background:
- Eosinopenia has been observed in patients with COVID-19.
- The relationship between eosinophil counts and COVID-19 severity requires further investigation.
Purpose of the Study:
- To examine peripheral blood eosinophil counts in COVID-19 patients.
- To determine if eosinophil counts are associated with COVID-19 disease severity.
Main Methods:
- Retrospective review of medical records for confirmed COVID-19 patients.
- Classification of patients into mild, moderate, and severe disease groups based on clinical outcomes.
- Comparison of clinical characteristics, laboratory results, and outcomes across severity groups.
Main Results:
- A total of 230 patients were analyzed, with 16.5% mild, 45.7% moderate, and 37.8% severe cases.
- Peripheral eosinophil counts significantly decreased as COVID-19 severity increased.
- Eosinopenia was present in 73.7% of mild, 86.7% of moderate, and 94.3% of severe COVID-19 cases (p=0.002).
Conclusions:
- Eosinopenia is significantly more prevalent in patients with severe COVID-19.
- Peripheral eosinophil count may serve as a potential indicator of COVID-19 severity.
Purpose:
Eosinopenia has been described in COVID-19. With this study, we aim to study the peripheral blood eosinophil counts in COVID-19 patients and to investigate whether there is an association between the peripheral blood eosinophil counts and disease severity of COVID-19.
Methods:
We revised the electronical medical records of confirmed COVID-19 patients with polymerase chain reaction (PCR) assays in the Groene Hart Ziekenhuis, Gouda, The Netherlands. We divided patients in mild, moderate and severe groups based on clinical severity of COVID-19. Clinical severity was based on the therapy needed and the outcome of patients. We compared clinical characteristics, laboratory results and outcome between the three groups.
Results:
Of the 230 patients included in this study, the mild, moderate and severe groups consisted of 16.5%, 45.7% and 37.8% of the included patients, respectively. The mean age was 68 years (IQR 57-78). 63% of patients were male. A significant decrease in the peripheral eosinophil counts was found corresponding to the increase of COVID-19 severity. In the mild, moderate and severe groups, the percentage of patients with eosinopenia was 73.7%, 86.7% and 94.3%, respectively (p value 0.002).
Conclusion:
Eosinopenia is significantly more frequent present in patients with a severe COVID-19.
