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Neutrophil to Lymphocyte Ratio (NLR) and Derived NLR Combination: A Cost-effective Predictor of Moderate to Severe
Sussan Kaboudanian Ardestani1, Mohammad Reza Salehi2, Bahareh Attaran3
1Department of Immunology, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran. ardestany@ut.ac.ir.
Insights
Neutrophil to lymphocyte ratio (NLR) and derived NLR (dNLR) effectively identify COVID-19 patients and predict disease severity. These hematologic markers aid in early diagnosis and prognosis for better patient outcomes.
Area of Science:
- Infectious Diseases
- Hematology
- Immunology
Background:
- Inflammation plays a critical role in the pathogenesis of Coronavirus disease 2019 (COVID-19).
- Early identification of patients with severe inflammation is crucial for timely and effective treatment.
- Hematologic markers may serve as valuable prognostic indicators for COVID-19 severity.
Purpose of the Study:
- To evaluate specific hematologic markers in COVID-19 patients.
- To assess the association between these markers and disease severity.
- To determine the diagnostic and prognostic value of selected ratios in COVID-19.
Main Methods:
- A cohort study involving 154 laboratory-confirmed COVID-19 patients and 55 healthy controls.
- Classification of COVID-19 patients into moderate, severe, and critical groups based on oxygen therapy requirements.
- Analysis of white blood cell count, neutrophil to lymphocyte ratio (NLR), platelet to monocyte ratio (PLR), macrophage to lymphocyte ratio (MLR), and derived NLR (dNLR).
Main Results:
- COVID-19 patients exhibited significantly higher levels of NLR, MLR, PLR, and dNLR compared to healthy subjects.
- Receiver operating characteristic (ROC) analysis demonstrated high diagnostic accuracy for NLR (AUC=0.923) and dNLR (AUC=0.910) in differentiating COVID-19 patients.
- NLR and dNLR showed moderate predictive value for mortality (AUC=0.726 and 0.735, respectively).
Conclusions:
- Neutrophil to lymphocyte ratio (NLR) and derived NLR (dNLR) are reliable hematologic markers for diagnosing COVID-19.
- These markers demonstrate significant potential in evaluating disease severity and predicting outcomes in COVID-19 patients.
- NLR and dNLR can aid clinicians in early risk stratification and management of COVID-19.
Abstract:
Inflammation is an essential contributor to Coronavirus disease 2019 (COVID-19). In this regard, finding a prognostic indicator is valuable because the treatment will be more effective if critical patients with high inflammation are diagnosed earlier. We aimed to evaluate some hematologic markers for COVID-19 and assess their association with the severity of the disease. A total of 154 COVID-19 patients were laboratory-confirmed and admitted to Imam Khomeini Hospital Complex, Tehran, Iran, from February 12, 2020, to April 4, 2020, and 55 healthy individuals were enrolled in the study. The severity of the patients' illnesses was classified into three subgroups according to the types of oxygen therapies (moderate (61), severe (28), and critical (43)) and examined the different ratios of total white blood cell (WBC) count, neutrophil to lymphocyte ratio (NLR), platelet to monocyte ratio (PLR), macrophage to lymphocyte ratio (MLR), derived NLR ratio (dNLR), and some biochemical tests. COVID-19 patients had higher levels of NLR, MLR, PLR, and dNLR than healthy subjects. receiver operating characteristic (ROC) analysis of the curve revealed that NLR and dNLR had a high diagnostic value to differentiate COVID-19 patients from healthy subjects (area under the curve [AUC]=0.923 and 0.910, respectively) and predict mortality (AUC=0.726 and 0.735, respectively). NLR and dNLR may be reliable markers to evaluate the severity of COVID-19. NLR and dNLR had a high diagnostic value for differentiating COVID-19 patients from healthy subjects, and they could predict the severity and outcome of the disease.
