Study correlating lymphocyte to monocyte ratio and platelet to lymphocyte ratio with the severity in COVID-19 patients: a cross sectional study

Prabhu S., Nishant Patil


Background: The objective of this study was to classify COVID-19 patients into severe and non-severe groups and to correlate lymphocyte to monocyte ratio and platelet to lymphocyte ratio with the severity of COVID-19 patients.

Methods: It was a cross sectional observational study conducted on hundred patients admitted to Victoria hospital, Department of Medicine, Bangalore Medical College and Research Institute, Bangalore between June 2020 and August 2020. Complete clinical data of the patients were taken and examined thoroughly and cases were diagnosed and severity was classified as per interim guidelines of World Health Organization (WHO) and diagnosis and treatment guidelines of COVID-19 by Ministry of Health and Family Welfare, Government of India. and compared and correlated with lymphocyte-monocyte ratio and platelet-lymphocyte ratio. A p<0.05 was considered significant. All analyses were performed using Statistical package for social sciences (SPSS) software version 10.

Results: The sample size in our study was 100 patients. The mean age of patients was 57.5 in severe and 35 in non severe COVID patients. Among these 67% were males and 33% were females. It was noted that, neutrophilia (median-88.5%) and lymphocytopenia (median-6.5) was seen among severe group. Also, the lymphocyte-monocyte ratio (LMR) was significantly low (p value-0.00*) and platelet-lymphocyte ratio (PLR) was high (p value-0.00*) and was statistically significant among severe COVID 19 patients.

Conclusions: LMR, PLR were significantly different between severe and non severe patients, so assessment of LMR, PLR may help identify high risk COVID 19 patients at an early stage. In our study LMR showed an acceptable efficiency to separate COVID 19 patients among severe and non severe group with a sensitivity of 82.4% and specificity of 84.8%. Whereas PLR showed high specificity of 93.9% and sensitivity of 64.7%.


COVID-19 patients, LMR, PLR

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