Lineage, Antimicrobial Resistance and Virulence of Citrobacter spp
Liyun Liu,
Liyun Qin,
Shuai Hao,
Ruiting Lan,
Baohong Xu,
Yumei Guo,
Ruiping Jiang,
Hui Sun,
Xiaoping Chen,
Xinchao LV,
Jianguo Xu,
Chuan Zhao
Affiliations
Liyun Liu
State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Liyun Qin
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050011, China
Shuai Hao
Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, China
Ruiting Lan
School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia
Baohong Xu
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050011, China
Yumei Guo
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050011, China
Ruiping Jiang
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050011, China
Hui Sun
State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Xiaoping Chen
State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Xinchao LV
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050011, China
Jianguo Xu
State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Chuan Zhao
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050011, China
Citrobacter spp. are opportunistic human pathogens which can cause nosocomial infections, sporadic infections and outbreaks. In order to determine the genetic diversity, in vitro virulence properties and antimicrobial resistance profiles of Citrobacter spp., 128 Citrobacter isolates obtained from human diarrheal patients, foods and environment were assessed by multilocus sequence typing (MLST), antimicrobial susceptibility testing and adhesion and cytotoxicity testing to HEp-2 cells. The 128 Citrobacter isolates were typed into 123 sequence types (STs) of which 101 were novel STs, and these STs were divided into five lineages. Lineages I and II contained C. freundii isolates; Lineage III contained all C. braakii isolates, while Lineage IV and V contained C. youngae isolates. Lineages II and V contained more adhesive and cytotoxic isolates than Lineages I, III, and IV. Fifty-one of the 128 isolates were found to be multidrug-resistant (MDR, ≥3) and mainly distributed in Lineages I, II, and III. The prevalence of quinolone resistance varied with Lineage III (C. braakii) having the highest proportion of resistant isolates (52.6%), followed by Lineage I (C. freundii) with 23.7%. Seven qnrB variants, including two new alleles (qnrB93 and qnrB94) were found with Lineage I being the main reservoir. In summary, highly cytotoxic MDR isolates from diarrheal patients may increase the risk of severe disease.
