Departments of Medicine and Molecular Virology and Microbiology, Baylor College of Medicine.
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas.
Clin Infect Dis. 2017 Oct 30;65(10):1736-1744. doi: 10.1093/cid/cix549.
Before 1945, Streptococcus pneumoniae caused more than 90% of cases of pneumonia in adults. After 1950, the proportion of pneumonia caused by pneumococcus began to decline. Pneumococcus has continued to decline; at present, this organism is identified in fewer than fewer10%-15% of cases. This proportion is higher in Europe, a finding likely related to differences in vaccination practices and smoking. Gram-negative bacilli, Staphylococcus aureus, Chlamydia, Mycoplasma, and Legionella are each identified in 2%-5% of patients with pneumonia who require hospitalization. Viruses are found in 25% of patients, up to one-third of these have bacterial coinfection. Recent studies fail to identify a causative organism in more than 50% of cases, which remains the most important challenge to understanding lower respiratory infection. Our findings have important implications for antibiotic stewardship and should be considered as new policies for empiric pneumonia management are developed.
在 1945 年以前，肺炎链球菌导致了超过 90%的成人肺炎病例。自 1950 年以来，肺炎球菌引起的肺炎比例开始下降。肺炎球菌的比例一直在持续下降；目前，这种病原体在不到 10%-15%的病例中被识别出来。这种比例在欧洲更高，这一发现可能与接种疫苗的做法和吸烟的差异有关。需要住院治疗的肺炎患者中，有 2%-5%的患者可培养出革兰氏阴性杆菌、金黄色葡萄球菌、衣原体、支原体和军团菌。病毒在 25%的患者中被发现，其中多达三分之一的患者存在细菌合并感染。最近的研究发现，超过 50%的病例未能确定病原体，这仍然是理解下呼吸道感染的最大挑战。我们的研究结果对抗生素管理具有重要意义，应在制定新的经验性肺炎管理政策时予以考虑。
