Evaluation of neutrophil to lymphocyte ratio as a predicted marker for the assessment of severe Coronavirus Disease-19 patients under a resource-constrained setting

PURPOSE: Analysis of clinical and laboratory markers are critical to determining the disease severity in Coronavirus Disease-19 (COVID-19) patients. The purpose of this study was to evaluate neutrophil to lymphocyte ratio (NLR) as a predicting marker of severe COVID-19 cases under the resource-constrained setting. METHODS & MATERIALS: This retrospective cross-sectional study was conducted among the purposively selected 71 COVID-19 patients admitted to the COVID hospital of the Bangabandhu Sheikh Mujib Medical University (BSMMU) from March 2021 to May 2021. The study population was grouped into mild to moderate COVID-19 (n=25) and Severe COVID-19 (n=46) patients based on the World Health Organization (WHO) COVID-19 disease severity classification. The predictive performance of the NLR for the assessment of severity in the COVID-19 population was determined by generating receiver operative characteristics (ROC) curves to obtain the best cut-off value. RESULTS: Among the study populations, none of the studied laboratory parameters was found to significantly varied between the mild to moderate and severe COVID-19 patients group except NLR. NLR values in severe COVID-19 patients (median: 12.57, IQR:3.79-18.6) were found significantly higher (P<0.01) than that of the mild to moderate COVID-19 group (median: 3.45; IQR: 2.71-8.16). Based on the ROC curve analysis, the best cut off value to determining the severe COVID-19 cases over mild to moderate COVID-19 patients was 4.26 with a sensitivity and specificity of 71.1% and 52.4% respectively. The area under the curve (AUC) was 0.701 with a 95% confidence interval (95% CI) of 0.557 to 0.845. CONCLUSION: This study demonstrated NLR as a low-cost laboratory predictor for the assessment of disease severity in COVID-19 patients that can be utilized under resource constraints settings.