Abstract: Objective To explore the value of Neutrophil-lymphocyte ratio (NLR) and Systemic immune-inflammatory index (SII) in the diagnosis of community-acquired pneumonia (CAP) patients in primary hospitals. Methods From January 2022 to September 2022, 70 CAP patients admitted to the First People's Hospital of Siyang County were selected as the CAP group. 70 healthy participants were recruited to the control group. The blood routine examination was analysed in all cases.Conduct ROC curve analysis on the diagnostic effectiveness of each index on CAP. Results Levels of white blood cells, neutrophils and lymphocytes in the experimental group were higher than those in the contronl group (P<0.05). Levels of red blood cells, hemoglobin and platelets were no statistical differences between the two groups (P>0.05). The levels of NLR and SII were higher in the experimental group than those in the contronl group, and the differences between the two groups were statistically significant (P<0.05). The results of the ROC curve showed that the area under the NLR curve was 0.76 (P<0.05), and the area under the SII curve was 0.73 (P<0.05). Conclusion Our study indicated that the levels of NLR and SII in community- acquired pneumonia patients were significantly higher than that in healty participants, they may be important auxiliary indexes for clinical diagnosis of CAP patients.

Key words: community-acquired pneumonia, neutrophil to lymphocyte ratio, system immune-inflammation index