Evaluation of C - Reactive Protein as a Prognosticator of the Course of Covid 19 Disease

Abstract

Diagnosis of COVID 19 is based on clinical manifestations, history of exposure, positive CT scan findings and laboratory tests. Inflammation plays a key role in pathogenesis of COVID 19. CRP is an acute phase protein in the serum and is also a surrogate marker for the pro inflammatory cytokine IL 6. Significant rise in CRP indicates clinically relevant inflammation. Aim and Objectives: To analyse the CRP levels in COVID 19 infected patients and to validate CRP as an indicator of the severity of SARS CoV 2 infection. Materials and Methods: This retrospective study was carried out at Chettinad Hospital and Research Institute, a tertiary care hospital situated on the outskirts of Chennai, India, for a period of 4 months. A total of 10263 patients were tested for COVID-19 by RT PCR. Viral RNA Extraction was automated and SARS CoV2 RTPCR performed with ROTOR GENE Q(QIAGEN) using SD Biosensor Real Time PCR kit. The CRP levels were measured using QDx Instacheck Fluorescence immunoassay system, Indianapolis, IN. Results: Among 10263 patients, 2694 (26.2%) patients tested SARS CoV-2 positive. CRP levels were measured for 1472 SARS CoV 2 patients (including both OP and IP). Among them 745 (50.6%) patients were found to be CRP reactive. Of the CRP reactive patients, 7 patients (0.9%) were <18 years, 190 patients (25.5%) were between 18 - 45 years and 548 patients (73.5%) were >45 years. Of the 592 patients with elevated CRP levels, 167 patients were from ICU and 425 patients were from non-ICU. Highly elevated CRP levels of >100mg/L were found in 65% (n=109) of the COVID positive ICU patients and 23% (n=101) of the non-ICU patients. Increased CRP levels were noted in SARS CoV- 2 infected individuals. Elevated CRP was common among elder patients aged >45 years and in males. Conclusion This study concludes that the significant rise of CRP levels was noted in hospitalized SARS CoV 2 positive patients aged > 45 years. Thus, estimating the early rise of serum CRP levels in SARS CoV-2 patients is a well affordable and less invasive parameter to guide the clinicians that is readily available in all the health care centers.