Dynamics of microbiota in ventilated associated pneumonia

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K17078
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Emergency medicine
• Research Institution: University of Occupational and Environmental Health, Japan
• Principal Investigator: Otsuji Ken 産業医科大学, 大学病院, 修練指導医 (50770244)
• Research Collaborator: Fukuda Kazumasa ; Ogawa Midori ; Kamochi Masayuki ; Saito Mitsumasa
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 誤嚥性肺炎 / 細菌叢解析 / 嫌気性菌 / 人工呼吸器

Outline of Final Research Achievements

It is often difficult to identify the causative bacteria in patients with aspiration pneumonia via the culture method. To develop a treatment strategy for patients with aspiration pneumonia, we evaluated the changes in microbiota of oral cavities and lower respiratory tracts in cases of aspiration pneumonia using the clone library analysis based on highly accurate 16S rRNA gene sequencing. Twenty-two mechanically ventilated patients with aspiration pneumonia treated in University of Occupational and Environmental Health Japan were recruited. The changes of microbiota in the saliva were not clear. On the other hand, the proportion of anaerobes was significantly reduced during mechanical ventilation (before administration of antibiotics) in the tracheal aspirate. It is suggested that anaerobes in the lower respiratory tract were markedly reduced by mechanical ventilation including oxygen administration.

Free Research Field

細菌叢解析

Academic Significance and Societal Importance of the Research Achievements

昨今、抗菌薬耐性菌の出現が世界的に問題となっており、抗菌薬の適正使用が求められている。今回の、遺伝子工学的手法により新たに得られた結果を踏まえると、誤嚥性肺炎症例の下気道において、人工呼吸器管理中に嫌気性菌が著減することを前提とした抗菌薬選択が必要であると考えられる。不適切な抗菌薬選択を減らすことが期待でき、抗菌薬耐性菌の出現防止、誤嚥性肺炎症例の生存率改善、さらには医療費削減にも期待できる可能性がある。