目的:探究血清PCT检测在下呼吸道感染诊治中的应用。方法:选取我院2015年~2016年收治的80例下呼吸道感染患者作为研究组,选取体检健康员工80人作为对照组,进行血清PCT监测,观察PCT指标及研究组内PCT指标和预后关系。结果:对照组PCT阳性例数3(3.75%),研究组阳性例数75(93.75%),两组对比,差异具有统计学意义(P<0.05)。研究组依照PCT指标分为>10ng/m L、≤10ng/m L两组,>10组死亡7例;≤10组死亡3例,两组对比,差异具有统计学意义(P<0.05)。结论:血清PCT检测可以在下呼吸道感染临床诊断中作为诊断标准,PCT指标与预后存在关联。 Objective: To explore the application of serum PCT in diagnosis and treatment of lower respiratory tract infection. Methods: Eighty patients with lower respiratory tract infection admitted from 2015 to 2016 in our hospital were selected as the research group, and 80 healthy people were selected as the control group. Serum PCT was monitored and the relationship between the PCT index and the prognosis of PCT was observed. Results: There were 3 positive cases (3.75%) in the control group and 75 (93.75%) cases in the study group. The difference between the two groups was statistically significant (P <0.05). The study group was divided into two groups according to the PCT index:> 10ng / m L, ≤10ng / m L, 7 cases> 10 cases and 3 cases ≤10 cases. The difference between the two groups was statistically significant (P <0.05). Conclusion: Serum PCT can be used as a diagnostic standard in the clinical diagnosis of lower respiratory tract infection. There is a correlation between PCT and prognosis.