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Diagnostic value of white blood cell parameters for COVID-19: Is there a role for HFLC and IG?
Alexandra Myari1, Evangelia Papapetrou1, Christina Tsaousi1
1Hematology Lab, University General Hospital of Ioannina, Ioannina, Greece.
Insights
White blood cell count (WBC) and high fluorescence lymphocyte cells (HFLC) effectively diagnose mild to serious COVID-19. Immature granulocyte count (IG) indicates progression to critical illness, aiding triage and patient management.
Area of Science:
- Clinical diagnostics
- Hematology
- Infectious disease epidemiology
Background:
- The ongoing COVID-19 pandemic necessitates efficient diagnostic tools for patient triage and disease monitoring.
- Investigating biomarkers like white blood cell count (WBC) and its subsets, high fluorescence lymphocyte cells (HFLC), immature granulocyte count (IG), and C-reactive protein (CRP) is crucial for managing patient flow and predicting outcomes.
Purpose of the Study:
- To evaluate the diagnostic utility of WBC, HFLC, IG, and CRP in identifying COVID-19 during triage.
- To assess the predictive value of these biomarkers for disease progression to serious and critical conditions.
Main Methods:
- Clinical and laboratory data from 197 COVID-19 negative and 368 positive cases were analyzed.
- Patients were classified into mild, serious, and critical disease categories.
- Receiver operating characteristic curve and binary logistic regression analyses were employed to determine biomarker efficacy.
Main Results:
- WBC, neutrophil count (NEUT), and HFLC demonstrated strong ability to differentiate negative cases from mild and serious COVID-19.
- The combined WBC-HFLC marker showed high sensitivity and specificity for diagnosing mild and serious COVID-19.
- C-reactive protein (CRP) and lymphocyte count indicated progression to serious disease, while WBC, NEUT, IG, and neutrophil-to-lymphocyte ratio predicted critical illness.
Conclusions:
- Lymphopenia is not a reliable screening marker for COVID-19.
- HFLC serves as a valuable diagnostic marker for mild and serious COVID-19, both alone and in combination with WBC.
- IG is a significant indicator for progression to critical COVID-19 disease.
Introduction:
As the Coronavirus disease 2019 (COVID-19) pandemic is still ongoing with patients overwhelming healthcare facilities, we aimed to investigate the ability of white blood cell count (WBC) and their subsets, high fluorescence lymphocyte cells (HFLC), immature granulocyte count (IG), and C-reactive protein (CRP) to aid diagnosis of COVID-19 during the triage process and as indicators of disease progression to serious and critical condition.
Methods:
We collected clinical and laboratory data of patients, suspected COVID-19 cases, admitted at the emergency department of University General Hospital of Ioannina (Ioannina, Greece). We selected 197 negative and 368 positive cases, confirmed by polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2. COVID-19 cases were classified into mild, serious, and critical disease. Receiver operating characteristic curve and binary logistic regression analysis were utilized for assessing the diagnosing ability of biomarkers.
Results:
WBC, neutrophil count (NEUT), and HFLC can discriminate efficiently negative cases from mild and serious COVID-19, whereas eosinopenia and basopenia are early indicators of the disease. The combined WBC-HFLC marker is the best diagnostic marker for both mild (sensitivity: 90.6% and specificity: 64.1%) and serious (sensitivity: 90.3% and specificity: 73.4%) disease. CRP and Lymphocyte count are early indicators of progression to serious disease whereas WBC, NEUT, IG, and neutrophil-to-lymphocyte ratio are the best indicators of critical disease.
Conclusion:
Lymphopenia is not useful in screening patients with COVID-19. HFLC is a good diagnostic marker for mild and serious disease either as a single marker or combined with WBC whereas IG is a good indicator of progression to critical disease.
