ABSTRACT
We aimed to find the most useful biomarker by examining the prognostic effect of neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), platelet-lymphocyte ratio (PLR), and lymphocyte-C reactive protein ratio (LCR) in patients with coronavirus disease 2019 (COVID-19). Three hundred and four patients diagnosed with COVID-19 infection in our hospital within 5 months (April-August 2020) were examined. Laboratory values and demographic findings of the patients were analyzed retrospectively. Thirty-six patients were diagnosed with severe cases. The ratio of NLR, LMR, PLR, and LCR of patients with severe and those with nonsevere clinical symptoms were statistically analyzed. The NLR and PLR ratios of those with severe clinical symptoms were significantly higher (p < 0.001), the LCR rate was significantly lower (p < 0.001), and there was no significant difference in the LMR rate (p = 0.199). When we examined other peripheral blood parameters, we found that CRP was high, lymphocyte and monocyte were low (p < 0.001), but neutrophil (p = 0.416) and platelet (p = 0.998) were not statistically different between the groups. According to the results, routine blood values are abnormal in patients with COVID-19. NLR, PLR, and LCR ratios can be used as more significant biomarkers than other values in predicting the prognosis of patients.