免疫抑制患者重症社区获得性肺炎的病原学分布特点

Etiology of severe community-acquired pneumonia in immunocompromised patients

目的分析免疫抑制合并重症社区获得性肺炎患者的病原学分布情况,确定其基础疾病与感染微生物的关系。方法对2017年1月1日至2019年12月31日入住中日友好医院呼吸与危重症医学科(MICU)的119例重症社区获得性肺炎合并免疫抑制患者的病原学分布进行回顾性分析,其中男性65例(54.6%),年龄(59.3±14.5)岁,入MICU时序贯器官衰竭(SOFA)评分为6.7±3.6,急性生理与慢性健康(APECHE)Ⅱ评分为19.4±6.8。60例(50%)患者最终好转出院。长期使用激素是患者处于免疫抑制状态的最主要危险因素。计算不同病原微生物在原发病是否累及肺部患者中的差异及院内病死率的影响。结果99例(83.2%)患者检出阳性的病原学结果,混合感染发生率54.5%。位列前3位的病原体分别是肺孢子菌(55.6%)、巨细胞病毒(47.5%)和曲霉(23.2%)。细菌感染中最常见的是金黄色葡萄球菌,其次是铜绿假单胞菌和肺炎克雷伯菌。无基础肺部受累的患者发生肺孢子菌感染的风险明显高于有肺部受累的患者(64.3%vs 44.2%,P=0.046)。患者院内死亡与病原种类差异无统计学意义(P>0.05),但与是否存在混合感染相关(56.7%vs 33.9,P=0.013)。结论肺孢子菌和巨细胞病毒是ICU内免疫抑制患者重症社区获得性肺炎最常见的感染病原体,无肺部基础病变的患者肺孢子菌感染发生率更高。

Objective To analyze the etiology of severe community-acquired pneumonia(SCAP)in immunocompromised patients,and to investigate the relationship between underlying diseases and infectious microorganisms.Methods A retrospective analysis was performed on SCAP in immunocompromised patients admitted to the Fourth Department of Respiratory and Critical Medicine(MICU)of China-Japan Friendship Hospital from January 1,2017 to December 31,2019.A total of 119 SCAP patients were finally enrolled,including 65 males(54.6%),with an average age of(59.3±14.5)years.The average of Sequential Organ Failure Assessment(SOFA)score was 6.7±3.6 and the acute physiology and chronic health evaluation(APACHE)Ⅱscore was 19.4±6.8.Sixty(50%)of these patients were finally improved and discharged.Long-term glucocorticoid treatment was the main risk factor for immunocompromise.The difference of pathogenic microorganisms between patients with and without structural lung diseases,and the influence of different pathogenic microorganisms on hospital mortality were calculated,respectively.P<0.05 was considered to be statistically significant.Results In this study,99(83.2%)patients were identified to have positive etiological results,and the incidence of concurrent infection was 54.5%.The top three pathogens were Pneumocystis Jiroveci(55.6%),Cytomegalovirus(47.5%)and Aspergillus(23.2%).Staphylococcus aureus was the most common bacterium,followed by Pseudomonas aeruginosa and Klebsiella pneumoniae.The risk of Pneumocystis Jiroveci infection was significantly higher in patients without underlying lung diseases as compared to those with underlying lung diseases(64.3%vs.44.2%,P=0.046).The in-hospital mortality was not different among patients infected with different pathogens(all P>0.05),but was higher in those with mixed infections(56.7%vs.33.9%,P=0.013).Conclusions Pneumocystis Jiroveci and Cytomegalovirus were the most common pathogens in immunocompromised patients with severe community-acquired pneumonia,and the incidence of Pneumocystis Jiroveci was significantly higher in patients without underlying lung diseases.