Neutrophil/lymphocyte ratio and C-reactive protein in patients with COVID-19: correlations in deceased and surviving patients

Introduction: COVID-19 is caused by SARS-CoV-2 associated with the activation of the inflammatory process. Various studies have determined the importance of the neutrophil/lymphocyte ratio (NLR) in different inflammatory processes. C-reactive protein (CRP) is involved in several infectious processes as a marker of inflammation. Objective: To determine the values of NLR and CRP in COVID-19 patients and controls and to determine these values in COVID-19 survivors and deceased patients. Method: This retrospective study was conducted in patients with suspected COVID-19 from various clinical institutions in Portoviejo, Manabí, Ecuador, from March to June 2021. A total of 41 SARS-CoV-2-positive COVID-19 patients were included and evaluated. Patients were classified into two groups according to their results (survivors: 22 and deceased: 19). Result: Overall, lymphocyte counts, NLR, and CRP values increased significantly during COVID-19. It was observed that during the disease, there were more positive correlations between the different inflammatory parameters studied than between the controls. The results show that surviving patients had increased lymphocyte counts and CRP content compared to deceased patients; however, the latter presented the highest NLR values and the lowest lymphocyte values, establishing a prognostic value of severe evolution. The number of significant correlations observed in surviving and deceased patients was similar. Conclusion: This study suggests the importance of leukocytes and CRP in COVID-19 and a possible predictive value for the severe evolution of NLR in the disease.