Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, China.
School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang Province, China.
Antimicrob Resist Infect Control. 2021 Feb 27;10(1):43. doi: 10.1186/s13756-021-00911-0.
The study aimed to elucidate the species taxonomy, clinical manifestations, virulence gene profiles and antimicrobial susceptibilities of Aeromonas strains isolated from life-threatening bacteremia in southeastern China.
Clinical samples of Aeromonas causing bacteremia were isolated from a teaching hospital in Wenzhou from 2013 to 2018 and a retrospective cohort study was performed. Aeromonas strains were identified at species level by housekeeping gene gyrB. Virulence and drug resistance-associated genes were screened by polymerase chain reaction (PCR) and antimicrobial susceptibility testing (AST) was performed by the VITEK 2 Compact system.
A total of 58 Aeromonas isolated from patients with bacteremia were collected during 6 years (2013-2018). 58 isolates were identified to five different species, where Aeromonas dhakensis appeared to be the predominant species (26/58), followed by Aeromonas veronii (13/58), Aeromonas caviae (10/58), Aeromonas hydrophila (7/58) and Aeromonas jandaei (2/58). 16 of 58 patients had poor prognosis. Poor prognosis was significantly associated with liver cirrhosis and inappropriate empirical antimicrobials therapy. The progression of bacteremia caused by Aeromonas was extremely fast, especially in A. dhakensis infections. Virulence genes aer, lip, hlyA, alt, ast, and act, were detected at ratios of 24.1% (14/58), 62.1% (36/58), 65.5% (38/58), 58.6% (34/58), 15.5% (9/58) and 65.5% (38/58), respectively. Antimicrobial susceptibility testing exhibited that 9 out of 58 isolates were identified as multi-drug resistant (MDR) organism. The bla gene was identified in all 9 MDR isolates. bla, bla, bla, bla, bla and aac(6')-Ib-cr were detected in 4 isolates, 2 isolates, 1 isolate, 3 isolates, 8 isolates, and 3 isolates, respectively. The majority of Aeromonas strains maintained susceptible to 3rd generation cephalosporins, aminoglycosides, fluoroquinolones and furantoin.
The prevalence and dangerousness of Aeromonas infections, especially A. dhakensis, are underestimated in clinic. Continuous monitoring is essential to keep track of MDR Aeromonas due to the increasing prevalence recently and a more effective measure is required to control the spread of resistance determinants.
本研究旨在阐明从中国东南部危及生命的菌血症中分离出的气单胞菌的种系分类、临床表现、毒力基因谱和抗菌药物敏感性。
从 2013 年至 2018 年，从温州某教学医院的临床标本中分离出引起菌血症的气单胞菌，并进行回顾性队列研究。通过看家基因 gyrB 对气单胞菌菌株进行种水平鉴定。通过聚合酶链反应（PCR）筛选毒力和耐药相关基因，采用 VITEK 2 Compact 系统进行抗菌药物敏感性试验（AST）。
6 年间（2013-2018 年）共从菌血症患者中分离出 58 株气单胞菌。58 株分离株鉴定为 5 个不同种，其中嗜水气单胞菌为主要种（26/58），其次为维氏气单胞菌（13/58）、豚鼠气单胞菌（10/58）、温和气单胞菌（7/58）和气单胞菌（2/58）。58 例患者中有 16 例预后不良。预后不良与肝硬化和经验性抗菌药物治疗不当显著相关。气单胞菌引起的菌血症进展非常迅速，尤其是在嗜水气单胞菌感染中。检测到毒力基因 aer、lip、hlyA、alt、ast 和 act 的比例分别为 24.1%（14/58）、62.1%（36/58）、65.5%（38/58）、58.6%（34/58）、15.5%（9/58）和 65.5%（38/58）。抗菌药物敏感性试验显示，58 株分离株中有 9 株被鉴定为多药耐药（MDR）菌。所有 9 株 MDR 分离株均携带 bla 基因。4 株分离株中检出 bla、bla、bla、bla，2 株分离株中检出 bla，1 株分离株中检出 bla，3 株分离株中检出 bla，8 株分离株中检出 bla，3 株分离株中检出 aac(6')-Ib-cr。大多数气单胞菌菌株对第三代头孢菌素、氨基糖苷类、氟喹诺酮类和呋喃妥因保持敏感。
气单胞菌感染，尤其是嗜水气单胞菌感染的流行程度和危险性在临床上被低估。由于最近 MDR 气单胞菌的流行率不断上升，因此需要持续监测，以控制耐药决定因素的传播，并采取更有效的措施来控制耐药性的传播。
