PDF(Pubmed)
Abstract：
Carbapenem-resistant Acinetobacter baumannii (CRAB) is a common cause of ventilator-associated pneumonia (VAP) in intensive care unit (ICU) patients, but its infection and colonization state are difficult to distinguish. If the judgment is wrong, it may aggravate the abuse of antibiotics and further accelerate the evolution of drug resistance. We sought to provide new clues for the diagnosis, pathogenesis and treatment of CRAB VAP based on lower respiratory tract (LRT) microbiota.
A prospective study was conducted on patients with mechanical ventilation from July 2018 to December 2019 in a tertiary hospital. Multi-genomics studies (16S rRNA amplicon, metagenomics, and whole-genome sequencing [WGS]) of endotracheal deep aspirate (ETA) were performed.
Fifty-two ICU patients were enrolled, including 24 with CRAB VAP (CRAB-I), 22 with CRAB colonization (CRAB-C), and six CRAB-negative patients (infection-free) (CRAB-N). Diversity of pulmonary microbiota was significantly lower in CRAB-I than in CRAB-C or CRAB-N (mean Shannon index, 1.79 vs. 2.73 vs. 4.81, P < 0.05). Abundances of 11 key genera differed between the groups. Acinetobacter was most abundant in CRAB-I (76.19%), moderately abundant in CRAB-C (59.14%), and least abundant in CRAB-N (11.25%), but its interactions with other genera increased in turn. Metagenomics and WGS analysis showed that virulence genes were more abundant in CRAB-I than in CRAB-C. Multi-locus sequence typing (MLST) of 46 CRAB isolates revealed that the main types were ST208 (30.43%) and ST938 (15.22%), with no difference between CRAB-I and CRAB-C.
Lower respiratory tract microbiota dysbiosis including elevated relative abundance of Acinetobacter and reduced bacterial interactions, and virulence enrichment may lead to CRAB VAP.
A prospective study was conducted on patients with mechanical ventilation from July 2018 to December 2019 in a tertiary hospital. Multi-genomics studies (16S rRNA amplicon, metagenomics, and whole-genome sequencing [WGS]) of endotracheal deep aspirate (ETA) were performed.
Fifty-two ICU patients were enrolled, including 24 with CRAB VAP (CRAB-I), 22 with CRAB colonization (CRAB-C), and six CRAB-negative patients (infection-free) (CRAB-N). Diversity of pulmonary microbiota was significantly lower in CRAB-I than in CRAB-C or CRAB-N (mean Shannon index, 1.79 vs. 2.73 vs. 4.81, P < 0.05). Abundances of 11 key genera differed between the groups. Acinetobacter was most abundant in CRAB-I (76.19%), moderately abundant in CRAB-C (59.14%), and least abundant in CRAB-N (11.25%), but its interactions with other genera increased in turn. Metagenomics and WGS analysis showed that virulence genes were more abundant in CRAB-I than in CRAB-C. Multi-locus sequence typing (MLST) of 46 CRAB isolates revealed that the main types were ST208 (30.43%) and ST938 (15.22%), with no difference between CRAB-I and CRAB-C.
Lower respiratory tract microbiota dysbiosis including elevated relative abundance of Acinetobacter and reduced bacterial interactions, and virulence enrichment may lead to CRAB VAP.
摘要：
耐碳青霉烯鲍曼不动杆菌（CRAB）是重症监护病房（ICU）患者呼吸机相关性肺炎（VAP）的常见原因，但其感染和定植状态难以区分。如果判断是错误的，它可能会加剧抗生素的滥用，并进一步加速耐药性的演变。我们试图为诊断提供新的线索，基于下呼吸道（LRT）菌群的CRABVAP的发病机制和治疗。
对2018年7月至2019年12月在三级医院接受机械通气的患者进行了一项前瞻性研究。多基因组学研究(16SrRNA扩增子，宏基因组学，和气管内深部抽吸物（ETA）的全基因组测序[WGS]）。
纳入52名ICU患者，包括24个带有CRABVAP（CRAB-I）的设备，22与CRAB定殖（CRAB-C），和6名CRAB阴性患者（无感染）（CRAB-N）。CRAB-I的肺部微生物群多样性显着低于CRAB-C或CRAB-N（平均Shannon指数，1.79vs.2.73vs.4.81,P<0.05)。11个关键属的丰度在组间不同。CRAB-I中不动杆菌含量最高(76.19%),CRAB-C含量中等（59.14%），CRAB-N含量最低(11.25%)，但它与其他属的相互作用又增加了。宏基因组学和WGS分析表明，CRAB-I中的毒力基因比CRAB-C中的毒力基因更丰富。46株CRAB分离株的多位点序列分型(MLST)显示主要类型为ST208(30.43%)和ST938(15.22%),CRAB-I和CRAB-C没有区别
下呼吸道微生物群菌群失调，包括不动杆菌的相对丰度升高和细菌相互作用减少，毒力富集可能导致CRABVAP。
对2018年7月至2019年12月在三级医院接受机械通气的患者进行了一项前瞻性研究。多基因组学研究(16SrRNA扩增子，宏基因组学，和气管内深部抽吸物（ETA）的全基因组测序[WGS]）。
纳入52名ICU患者，包括24个带有CRABVAP（CRAB-I）的设备，22与CRAB定殖（CRAB-C），和6名CRAB阴性患者（无感染）（CRAB-N）。CRAB-I的肺部微生物群多样性显着低于CRAB-C或CRAB-N（平均Shannon指数，1.79vs.2.73vs.4.81,P<0.05)。11个关键属的丰度在组间不同。CRAB-I中不动杆菌含量最高(76.19%),CRAB-C含量中等（59.14%），CRAB-N含量最低(11.25%)，但它与其他属的相互作用又增加了。宏基因组学和WGS分析表明，CRAB-I中的毒力基因比CRAB-C中的毒力基因更丰富。46株CRAB分离株的多位点序列分型(MLST)显示主要类型为ST208(30.43%)和ST938(15.22%),CRAB-I和CRAB-C没有区别
下呼吸道微生物群菌群失调，包括不动杆菌的相对丰度升高和细菌相互作用减少，毒力富集可能导致CRABVAP。
