Meghna C¹* and Shashikala N²

¹Associate Professor, Department of Microbiology, Pondicherry Institute of Medical Sciences1, Puducherry, India
²Professor, Department of Microbiology, Pondicherry Institute of Medical Sciences2, Puducherry, India

*Corresponding Author: Meghna C, Associate Professor, Department of Microbiology, Pondicherry Institute of Medical Sciences1, Puducherry, India.

Received: June 25, 2025; Published: July 17, 2025

Abstract

C-reactive protein (CRP) is a non-specific homopentameric acute phase protein that is produced by hepatocytes and elevated in acute infection or inflammation. The use of CRP as a biomarker in COVID-19 may present a quick and accessible tool in clinical management, trigger longer periods of enhanced observation, provide information around likely disease progression and assist with early therapeutic, ventilation and palliative care discussions. The study was a hospital – based retrospective analytical study. The study was done in PIMS, a tertiary care centre, situated in Puducherry, Tamil Nadu, South India and it is a designated covid hospital (by Government of Puducherry). The C-reactive protein (CRP) values were collected from the section registers for the period of one and a half years (May 2020 to December 2021, which includes all the three waves of covid 19 infection). Highest CRP value recorded in this study was 305 mg/L. Optimal cut-off threshold (Youden index) for CRP was 38.6 mg/L (For severe covid 19 disease). ROC curve and its co-ordinates corresponded to a CRP value of 38.6 as the best cut-off threshold for severe covid 19 disease. With this cut-off threshold, it gave maximum sensitivity of 76.5% and specificity of 74.8%, positive predictive value (PPV) of 67.48%, and negative predictive value (NPV) of 98.62%. A threshold cut-off of CRP ≥36.8 mg/L proved to be a good predictor of severity of covid 19 disease.

Keywords: C-Reactive Protein; Covid 19; Severe Covid 19; Moderate Covid 19; Breathlessness; Sore Throat; Acute Phase Protein

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Citation

Citation: Meghna C and Shashikala N. “Assessing the Severity of COVID-19 Disease Using C-Reactive Protein as a Prognostic Indicator".Acta Scientific Microbiology 8.8 (2025): 03-10.

Copyright

Copyright: © 2025 Meghna C and Shashikala N. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.