The Relation between Neutrophil-Lymphocyte Ratio and Inflammatory Markers in Assessing the Severity of COVID-19 Disease
Background: The identification of effective laboratory biomarkers together with the clinical presentation is crucial to categorize the severity of the disease. The following biomarkers have been identified: Neutrophil-lymphocyte ratio (NLR), Inflammatory C-reactive protein (CRP), Serum Ferritin levels, Serum Lactate Dehydrogenase. Cytokine storm is one of the most dreaded complications of COVID19 that can be treated effectively by early identification. The current study is to test and confirm the prognostic value of NLR as an economic and reliable indicator of COVID19.
Methodology: The current study is a retrospective observational study. The data of COVID-19 patients admitted to a tertiary care hospital from the 25th of August, 2021 to the 25th of September, 2021 was analyzed. Patients were categorized into mild, moderate, and severe groups based on ICMR guidelines. The blood reports from the day one of admission were taken into consideration for this study.
Results: The study included 71 patients consisting of 29 males and 42 females, with a male to female ratio of 0.69. In the present study, 52 patients are with mild disease (Males-19; Females-33), 12 (males-4; females-8) are in the moderate category, and 7 (males-1; females-6) patients have severe disease. In mild patients, the mean CRP was 4.01mg/L, the mean serum Ferritin was 214.23mcg/L, and the mean NLR was 3.62. In patients with moderate severity, the mean CRP was 5.86mg/L, the mean serum Ferritin was 383.62mcg/L, and the mean NLR was 5.67. In patients with severe disease, the mean CRP was 22.71mg/L, the mean serum Ferritin was 805mcg/L, and the mean NLR was 15.3.
Conclusion: The study showed that there is a gradual increase in CRP, Serum Ferritin, and NLR with the increase in severity of disease from mild to severe. NLR is gradually increasing with increasing mean CRP and serum Ferritin levels Hence, NLR can be used as a reliable predictor of the severity of the disease instead of CRP and serum Ferritin in places lacking adequate facilities.
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