PREDICTIVE ROLE OF NLR, d-NLR, LMR AND PLR IN DISEASE SEVERITY OF COVID-19 PATIENTS

Abstract

Introduction: On 31st March 2020 WHO declared coronavirus disease 2019 as global pandemic caused by SARS-COV-2019. Covid-19 virus elicits severe inammatory reaction upon entering the body. This inammation is also reected in blood parameters like complete blood count, liver function test, renal function tests etc. By studying some of these parameters, we have tried to determine the severity of covid-19 infection. Aims And Objectives: To review the blood parameters that are affected by virus triggered inammation in covid-19 disease. Materials And Methods: An observational cross-sectional study was conducted in a tertiary COVID-19 care hospital over a course of 4 months. Infection was diagnosed by RT-PCR method done on either nasopharyngeal or oropharyngeal swab. Patients were grouped into severe and nonsevere category according to the interim guidelines for diagnosis and treatment issued by WHO. There were 50 severe and 100 non severe cases in total. T-test was applied for comparing continuous variables and ROC curve was applied to determine the cut off values of various parameters studied. P value <0.05 was recognized as statistically signicant. Results: The difference between mean value of NLR in severe group (11.72+8.57) and in non-severe group (2.57+1.53) was signicant with the p value of <0.0001. The ROC curve shows AUC of 0.8835 and cut-off value of >3.5 with 80% sensitivity and 82% specicity. Similar results were found with d-NLR (7.59+5.71 vs 1.95+1.06) with p value <0.0001 with ROC-AUC of 0.8808 and cut-off of >2.65 with 80% sensitivity and 80% specicity. The ndings of LMR were also signicant with mean value of 4.22+3.75 in severe, 6.80+3.19 in non-severe, p value of <0.0001, ROCAUC of 0.7663, cut-off of <4.65 (72% sensitivity and 75% specicity). The ndings of PLR had mean value of 263.33+179.47 in severe, 128.46+73.70 in non-severe, p value of <0.0001, ROC-AUC is 0.7237, cut off of >47.50 (72% sensitivity and 72% specicity. Conclusion: The values of NLR, d-NLR, LMR, and PLR varied signicantly among severe and non-severe cases. Thus, they have a good predictive role in disease severity in covid-19 infection. These variables are easy to assess and may help in triage and better management.