Diagnostic Role of Platelet-Lymphocyte Ratio and Platelet Parameters in COVID-19 Disease

Document Type : Original Research

Authors
1 Associate Professor, Department of Pathology, PSG Institute of Medical Sciences and Research, Coimbatore, India
2 Professor, Department of Pathology, PSG Institute of Medical Sciences and Research, Coimbatore, India
3 Associate Professor, Department of Community Medicine, PSG Institute of Medical Sciences and Research, Coimbatore, India
4 Assistant Professor, Department of Pathology, PSG Institute of Medical Sciences and Research, Coimbatore, India
Abstract
Backgrounds: This study aimed to analyze the applicability of platelet parameters in assessing the severity of COVID-19 disease.

Materials & Methods: Patients with RT-PCR confirmed COVID-19 in the pathology department of a tertiary care hospital in south India from June to December 2020 were included in this study. Clinical details and laboratory parameters of these patients were obtained. The difference between the studied variables in two groups was assessed using independent t-test. The optimum cut-off value of platelet to lymphocyte ratio (PLR) to differentiate between the tested groups was estimated using ROC (receiver operator curve) analysis.

Findings: This study was conducted on 218 COVID-19 patients, of whom 17.9% showed thrombocytopenia at the time of admission. Among the hematological parameters, PLR, absolute lymphocyte count (ALC), platelet distribution width (PDW), D-dimer, and erythrocyte sedimentation rate (ESR) were significantly different between the ICU (intensive care unit) and non-ICU groups. Increased PLR values were associated with the disease severity.

Conclusion: PLR could be used as an additional biomarker in assessing the severity of COVID-19 disease, and a cut-off value of 210.27 is optimal to differentiate severe COVID-19 disease from its mild and moderate forms with 79% specificity.

Keywords

Subjects


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