Ba813harboringBacillus cereus, genetically closely related toBacillus anthracis, causing nosocomial bloodstream infection: Bacterial virulence factors and clinical outcome
Ba813harboringBacillus cereus, genetically closely related toBacillus anthracis, causing nosocomial bloodstream infection: Bacterial virulence factors and clinical outcome
复制标题
DOI：
10.1371/journal.pone.0235771
复制
发表时间：
2020-07-13
期刊：
影响因子：
3.7
通讯作者：
Kaku, Mitsuo
中科院分区：
文献类型：
--
作者：
Aoyagi, Tetsuji;Oshima, Kengo;Kaku, Mitsuo
蜡样芽孢杆菌（Bacillus cereuscereus）是医院内常见的导管相关性血流感染（bather-related bloodstream infections，BSIs）的病原菌，其染色体标记物Ba 813存在于严重感染和院内BSI患者中。然而，Ba 813（+）B cereus的细菌学特征和临床特征尚不清楚。对53例蜡样芽胞杆菌BSI患者进行了检查。对分离株进行了Ba 813、B、炭疽相关和食物中毒相关毒力、多位点测序分型和生物膜形成的评价。回顾性分析患者的临床记录。53个分离物由两个不同分支中的29个不同序列类型组成。其中17个（32%）B.cereusisolates（包括5个序列类型）具有Ba 813，属于Clade-1/Cereus-III谱系，该谱系与Anthracis谱系关系最密切。Ba 813（+）菌株的肠毒素基因频率低于Clade-2菌株（n = 4），但与Clade-1菌株无差异; Ba 813（+）菌株的生物膜形成率分别显著低于Clade-1/non-Cereus-III（n = 22）和Clade-2菌株。与Clade-1/non-Cereus-III和Clade-2B. cereus相比，Ba 813（+）菌株更常见于老年患者、留置中心静脉导管而非外周静脉导管的患者以及BSI发病前住院时间较长的患者。未观察到疾病严重程度或死亡率的显著差异。虽然Clade-1/Cereus III中的两株tenBa 813（-）菌株分离自CNS并发症患者，但Clade-1/Cereus III菌株之间的细菌谱和临床特征没有观察到显著差异。总之，我们的报告表明，携带Ba 813的蜡样芽孢杆菌菌株，遗传上与炭疽芽孢杆菌密切相关，是医院环境中丰富的蜡样芽孢杆菌菌株，可能导致导管相关的医院内BSI。但是，这并不影响临床结局。
Bacillus cereuscommonly causes catheter-related bloodstream infections (BSIs) in hospital settings, and occasionally occurs fatal central nervous system (CNS) complications.B.cereusharboringBa813, a specific chromosomal marker ofBacillus anthracis, has been found in patients with severe infection and nosocomial BSI. However, the bacteriological profile and clinical feature ofBa813(+)B.cereusare unclear. Fifty-three patients withB.cereusBSI were examined. Isolates were evaluated forBa813,B.anthracis-related and food poisoning-related virulence, multilocus sequencing typing, and biofilm formation. Patients' clinical records were reviewed retrospectively. The 53 isolates were comprised of 29 different sequence types in two distinct clades. Seventeen of the 53 (32%)B.cereusisolates including five sequence types possessedBa813and were classified into Clade-1/Cereus-III lineage which is most closely related to Anthracis lineage. NoB.cereuspossessedB.anthracis-related virulence genes.Ba813(+) strains showed a lower prevalence of enterotoxin genes than Clade-2 strains (n = 4), but no difference from Clade-1.Ba813(+) strains showed significantly lower biofilm formation than Clade-1/non-Cereus-III (n = 22) and Clade-2 strains, respectively. Compared to Clade-1/non-Cereus-III and Clade-2B.cereus,Ba813(+) strains were isolated more frequently from elderly patients, patients with indwelling central venous catheter rather than peripheral venous catheter, and patients who remained in the hospital for longer before BSI onset. No significant differences in disease severity or mortality were observed. Though two of the tenBa813(-) strains in Clade-1/Cereus III were isolated from the patients with CNS complication, no significant difference was observed in the bacterial profile and clinical characteristics among Clade-1/Cereus III strains. In conclusion, our report suggested thatBa813-harboringB.cereusstrains, genetically closely related toB.anthracis, were abundant amongB.cereusstrains in the hospital setting, and might cause catheter-related nosocomial BSI. However, it did not affect the clinical outcomes.