Role Of Neutrophil Lymphocyte Ratio (Nlr) In Predicting Disease Severity In Covid -19: A Multicenter Retrospective Study

Background: Covid-19, an extremely contagious and rapidly spreading viral infection, caused by a novel corona virus SARS-COV-2 was first reported in China on December 5, 2019. It was declared as pandemic by WHO on March 11, 2020. The novel infection yet under research exhibits wide spectrum of severity ranging from no symptom to severe pneumonia leading even to death.Aim: To evaluate the role of NLR as a prognostic indicator for severe COVID-19, due to its positive correlation with disease severity, easy accessibility and low cost.Methods: It was multicenter retrospective observational study conducted in COVID wards of two tertiary care hospitals of Lahore treating COVID-19 patients between March and June 2020. A predesigned proforma was filled to collect the data. SPSS 21 was used for statistical analysis of this research.Results: Record of 100 COVID-19 patients admitted between March and June 2020 fulfilling the inclusion criteria was included in the study. All patients were divided into two groups. Non-severe group included 37 patients while severe group included 63 patients. The mean age of study population was 56 years with male predominance (63%). Overall, 50% patients in non-severe group and 71% patients in severe group had some co-existent comorbidity. Fever and cough were the most commonly reported symptoms in both groups while shortness of breath was more commonly reported in severe group (74.2%). The mean NLR in non-severe group was 4 as compared to 12 in severe group.Conclusion: Higher Neutrophil lymphocyte ratio (NLR) is associated with severe COVID-19 and can be used as an effective tool to predict progression of non-severe disease to severe disease.