Chen Po-Lin, Tsai Pei-Jane, Chen Chang-Shi, Lu Ying-Chuan, Chen Hung-Mo, Lee Nan-Yao, Lee Ching-Chi, Li Chia-Wen, Li Ming-Chi, Wu Chi-Jung, Ko Wen-Chien
Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan; Graduate Institute of Clinical Medicine, National Cheng Kung University, Tainan, Taiwan.
Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan, Taiwan; Research Center of Infectious Disease and Signaling, National Cheng Kung University, Tainan, Taiwan.
J Microbiol Immunol Infect. 2015 Dec;48(6):618-24. doi: 10.1016/j.jmii.2014.08.007. Epub 2014 Nov 1.
Although aeromonads are important pathogens causing invasive infections in southern Taiwan, Aeromonas-associated intestinal infections have been rarely mentioned.
The aim of this study was to understand the frequency of isolation and clinical significance of aeromonads recovered from adult stool samples in southern Taiwan.
During a 15-month study period, 514 adults with diarrhea and 167 asymptomatic controls were prospectively screened for the presence of aeromonads in stools. The identity of Aeromonas species was determined by the rpoD sequencing. Clinical information was retrieved from medical records, and in vitro cytotoxicity assay and polymerase chain reaction detection of putative virulent genes were performed.
Thirteen (2.5 %) of 514 diarrheal patients and six (3.6%) of 167 asymptomatic controls had Aeromonas isolates in their stools. Of 11 diarrheal patients with available clinical information, Aeromonas veronii, the predominant species, was noted in six patients, and another potential enteropathogen was present in four patients. The cytotoxicity of A. veronii isolates to the HT-29 cell line was more potent in the isolates from diarrheal patients than those from asymptomatic controls (p = 0.015). The cytotoxicity of A. veronii isolates was more potent than that of A. caviae from symptomatic patients (p = 0.001). Putative virulence markers, including AHCYTONE, ascV, ascF-ascG, and aexT, were detected exclusively in A. veronii. The presence of the ascV gene was associated with cytotoxicity in A. veronii isolates. All Aeromonas isolates were susceptible to varied antimicrobial agents, except ampicillin/sulbactam.
A. veronii is the predominant species in stools from individuals with or without diarrhea in southern Taiwan.
虽然气单胞菌是台湾南部引起侵袭性感染的重要病原体，但与气单胞菌相关的肠道感染却鲜有提及。
本研究旨在了解台湾南部成年粪便样本中气单胞菌的分离频率及临床意义。
在为期15个月的研究期间，对514例腹泻成人和167例无症状对照者进行前瞻性粪便气单胞菌筛查。通过rpoD测序确定气单胞菌的种类。从病历中获取临床信息，并进行体外细胞毒性试验和推定毒力基因的聚合酶链反应检测。
514例腹泻患者中有13例（2.5%）粪便中气单胞菌分离阳性，167例无症状对照者中有6例（3.6%）粪便中气单胞菌分离阳性。在有可用临床信息的11例腹泻患者中，主要菌种维氏气单胞菌在6例患者中被检出，另外4例患者中存在另一种潜在肠道病原体。维氏气单胞菌分离株对HT-29细胞系的细胞毒性在腹泻患者分离株中比无症状对照者分离株更强（p = 0.015）。有症状患者的维氏气单胞菌分离株的细胞毒性比豚鼠气单胞菌更强（p = 0.001）。推定毒力标志物，包括AHCYTONE、ascV、ascF-ascG和aexT，仅在维氏气单胞菌中被检测到。ascV基因的存在与维氏气单胞菌分离株的细胞毒性相关。除氨苄西林/舒巴坦外，所有气单胞菌分离株对多种抗菌药物敏感。
维氏气单胞菌是台湾南部腹泻或非腹泻个体粪便中的主要菌种。
