目的:探讨外周血白细胞、C-反应蛋白(CRP)、中性粒细胞CD64的早期表达在儿童社区获得性肺炎诊断中的价值。方法:依据病原体不同,将90例肺炎患儿分为细菌感染组(30例)、病毒感染组(27例)以及支原体感染组(33例),记录患儿入院时外周血白细胞、CRP水平和CD64指数。结果:细菌感染组白细胞、CRP水平和CD64指数显著高于其他两组,差异有统计学意义(P<0.05);CD64指数的敏感性(93.3%)远高于CRP(76.7%);而病毒感染组及支原体感染组相比,差异无统计学意义(P>0.05)。结论:儿童肺炎细菌感染早期,外周血白细胞、CRP及CD64显著升高,以CD64最为敏感,可以作为儿童肺炎细菌感染早期诊断依据。 Objective: To investigate the early expression of peripheral blood leucocyte, C-reactive protein (CRP) and neutrophil CD64 in the diagnosis of community-acquired pneumonia in children. Methods: Ninety children with pneumonia were divided into bacterial infection group (n = 30), virus infection group (n = 27) and mycoplasma infection group (n = 33) according to different pathogens. The levels of peripheral blood leukocytes CD64 index. Results: The white blood cells, CRP level and CD64 index of bacterial infection group were significantly higher than those of the other two groups (P <0.05). The sensitivity of CD64 index (93.3%) was much higher than that of CRP (76.7% There was no significant difference between infection group and mycoplasma infection group (P> 0.05). Conclusion: In the early stage of childhood pneumonia bacterial infection, the peripheral blood leucocytes, CRP and CD64 are significantly increased, most likely to be CD64, which can be used as the early diagnosis basis for bacterial pneumonia in children.