病原学阳性与阴性的医院获得性肺炎患者临床特征及预后比较

Comparison of Clinical Characteristics and Outcomes of Patients with Culture-negative versus Culture-positive Hospital Acquired Pneumonia

目的 探讨病原学阳性与阴性的医院获得性肺炎(HAP)患者临床特征以及预后的差异。方法 收集2015年1月至2016年12月HAP患者临床资料,采集确诊患者第1天、第3天、第5天血液标本,测定白细胞、C-反应蛋白、降钙素原、B型钠尿肽与乳酸水平。患者随访至死亡或自诊断HAP起90d。结果 共纳入161例HAP患者,病原学阳性86例,病原学阴性75例。病原学阴性组与阳性组比较PaO_2/FiO_2更高(P=0.012),机械通气(MV)时间更短(P<0.001)。2组患者确诊后第1天、第3天、第5天血清学标志物均无统计学差异(P>0.05)。与病原学阳性组比较,病原学阴性组经验治疗方案改变率低(P<0.001),具有较短的抗菌治疗时间(P=0.001)与住院时间(P=0.001),住院病死率低(P=0.042);2组28 d与90 d病死率无统计学差异(P>0.05)。结论 病原学阴性HAP患者具有较高PaO_2/FiO_2,MV、住院、抗菌治疗时间均较短,住院病死率低。

Objective To compare the clinical characteristics and outcomes of patients with and those without microbiologically confirmed hospital-acquired pneumonia(HAP).Methods Clinical data of patients with HAP from January 2015 to December 2016 were collected.The white blood cell(WBC)count and serum levels of C-reactive protein(CRP),procalcitonin(PCT),B-type natriuretic peptide(BNP),and lactic acid(LAC)were determined on days 1,3,and 5 after the diagnosis of HAP.All patients were followed uptill death or 90 days after diagnosis.Results A total of 161 HAP patients were included in the study;86 had culture-positive while 75 had culture-negative HAP.Culture-negative patients had higher PaO2/FiO2 ratios(P=0.012)and a shorter duration of mechanical ventilation(MV,P<0.001)compared with culture-positive patients.There was no significant difference between the two groups in the WBC count and CRP,BNP,and LAC levels at 1,3,and 5 days(P>0.05).The culture-negative group had fewer changes in empiric treatment(P<0.001),a shorter duration of antibacterial treatment(P=0.001),shorter hospital stay(P=0.001),and lower hospital mortality(P=0.042).There was no significant difference between groups in the 28-and 90-day mortality.Conclusion Culture-negative HAP was associated with higher PaO2/FiO2 ratios,shorter duration of MV and antibacterial treatment,shorter hospital stay,and lower hospital mortality.