Neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and systemic immune-inflammation index in patients with COVID-19-associated pneumonia

Abstract

Introduction: There are hematological parameters that correlate severity and predict mortality mainly in septic and inflammatory states. Objective: To correlate the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and systemic immune-inflammation index (SIII) with COVID-19 severity. Method: Descriptive, analytical, retrospective study of patients with COVID-19 pneumonia, in whom NLR, PLR and SIII were analyzed. Results: One-hundred patients were included, 54 men and 46 women, with a mean age of 49.4 ± 19.3 years. NLR, PLR and SIII means were 10.7 ± 10.9, 290.1 ± 229.2, and 2.6 ± 3.4 x 109, respectively. In 54 %, pneumonia was mild, and in 46 %, severe. Regarding hospital outcomes, 75 % were dis-charged due to improvement and 25 % died. NLR, PLR and SIII means of the patients who died versus the patients who improved were 20.4 ± 16.9 versus 7.5 ± 4.9 (p = 0.001), 417.1 ± 379.7 versus 247.7 ± 127.4 (p = 0.038) and 4.8 ± 6.1 versus 1.9 ± 1.2 × 109 (p = 0.030), respectively. Conclusion: Hematological parameters can be used in patients with COVID-19-as-sociated pneumonia as predictors of severity and prognosis.