Abstract：
BACKGROUND: The culture method is the gold standard for identifying pathogenic bacteria in patients with pneumonia but often does not reflect the exact bacterial flora in pulmonary lesions of pneumonia, partly owing to easiness or difficulties in culturing certain bacterial species. We aimed to evaluate bacterial flora in bronchoalveolar lavage fluid (BALF) samples directly obtained from pneumonia lesions using 16S ribosomal RNA (rRNA) gene analysis to compare the results of the BALF culture method in each category of pneumonia.
METHODS: Bacterial florae were detected by a combination of the culture method, and the clone library method using the 16S rRNA gene sequencing in BALF directly obtained from pneumonia lesions in pneumonia patients from April 2010 to March 2020 at the University of Occupational and Environmental Health, Japan, and affiliated hospitals. Clinical information of these patients was also collected, and lung microbiome was evaluated for each pneumonia category.
RESULTS: Among 294 pneumonia patients (120 with community-acquired pneumonia (CAP), 101 with healthcare-associated pneumonia (HCAP), and 73 with hospital-acquired pneumonia (HAP)), significantly higher percentages of obligate anaerobes were detected in CAP than in HCAP and HAP patients by the clone library method. Corynebacterium species were significantly highly detected in HAP patients and patients with cerebrovascular diseases than in patients without, and Streptococcus pneumoniae was frequently detected in patients with diabetes mellitus.
CONCLUSIONS: Obligate anaerobes may be underestimated in patients with CAP. Corynebacterium species should be regarded as the causative bacteria for pneumonia in patients with HAP and cerebrovascular diseases.
METHODS: Bacterial florae were detected by a combination of the culture method, and the clone library method using the 16S rRNA gene sequencing in BALF directly obtained from pneumonia lesions in pneumonia patients from April 2010 to March 2020 at the University of Occupational and Environmental Health, Japan, and affiliated hospitals. Clinical information of these patients was also collected, and lung microbiome was evaluated for each pneumonia category.
RESULTS: Among 294 pneumonia patients (120 with community-acquired pneumonia (CAP), 101 with healthcare-associated pneumonia (HCAP), and 73 with hospital-acquired pneumonia (HAP)), significantly higher percentages of obligate anaerobes were detected in CAP than in HCAP and HAP patients by the clone library method. Corynebacterium species were significantly highly detected in HAP patients and patients with cerebrovascular diseases than in patients without, and Streptococcus pneumoniae was frequently detected in patients with diabetes mellitus.
CONCLUSIONS: Obligate anaerobes may be underestimated in patients with CAP. Corynebacterium species should be regarded as the causative bacteria for pneumonia in patients with HAP and cerebrovascular diseases.
摘要：
背景：培养方法是鉴定肺炎患者病原菌的金标准，但往往不能反映肺炎肺部病变的确切细菌菌群，部分原因是培养某些细菌的容易或困难。我们旨在使用16S核糖体RNA（rRNA）基因分析评估直接从肺炎病变中获得的支气管肺泡灌洗液（BALF）样品中的细菌菌群，以比较BALF培养方法在每种肺炎中的结果。
方法：通过组合培养方法检测细菌菌群，2010年4月至2020年3月在职业与环境健康大学直接从肺炎患者的肺炎病灶中获得的BALF中使用16SrRNA基因测序的克隆文库方法，Japan,和附属医院。还收集了这些患者的临床信息，并评估了每个肺炎类别的肺部微生物组。
结果：在294例肺炎患者中（120例社区获得性肺炎（CAP），101与医疗保健相关肺炎（HCAP），73例医院获得性肺炎(HAP)，通过克隆文库方法，CAP中检测到的专性厌氧菌百分比明显高于HCAP和HAP患者。在HAP患者和有脑血管疾病的患者中，棒杆菌属的检出率明显高于无，在糖尿病患者中经常检测到肺炎链球菌。
结论：CAP患者的固有厌氧菌可能被低估。棒状杆菌应被视为HAP和脑血管疾病患者肺炎的致病菌。
方法：通过组合培养方法检测细菌菌群，2010年4月至2020年3月在职业与环境健康大学直接从肺炎患者的肺炎病灶中获得的BALF中使用16SrRNA基因测序的克隆文库方法，Japan,和附属医院。还收集了这些患者的临床信息，并评估了每个肺炎类别的肺部微生物组。
结果：在294例肺炎患者中（120例社区获得性肺炎（CAP），101与医疗保健相关肺炎（HCAP），73例医院获得性肺炎(HAP)，通过克隆文库方法，CAP中检测到的专性厌氧菌百分比明显高于HCAP和HAP患者。在HAP患者和有脑血管疾病的患者中，棒杆菌属的检出率明显高于无，在糖尿病患者中经常检测到肺炎链球菌。
结论：CAP患者的固有厌氧菌可能被低估。棒状杆菌应被视为HAP和脑血管疾病患者肺炎的致病菌。
