title: Changes in causative pathogens of acute cholangitis and their antimicrobial susceptibility over a period of 6 years.
abstract: OBJECTIVE
  We evaluated changes of causative pathogen in acute cholangitis and their antimicrobial susceptibility over six years and differences between community-acquired and hospital-acquired acute cholangitis at our institution.
  
  
  METHODS
  Medical records of 1,596 patients with acute cholangitis and biliary drainage between August 2006 and August 2012 were reviewed retrospectively. Cases were divided according to time: period 1 (August 2006-December 2008, n=645, 40.4%), period 2 (January 2009-August 2012, n=951, 59.6%). Cases were divided according to community-acquired cholangitis (n=1,397, 87.5%) and hospital-acquired cholangitis (n=199, 12.5%). Causative pathogens and antimicrobial susceptibility were investigated in each group.
  
  
  RESULTS
  Causative pathogen was isolated from bile culture in 1,520 out of 1,596 cases (95.2%). The three most frequently isolated Gram-negative bacteria were extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (n=485, 30.4%), E. coli (n=237, 13.2%), and Citrobacter freundii (n=110, 6.9%). Between periods 1 and 2, prevalence of ESBL-producing E. coli and Klebsiella pneumoniae did not show significant change (36.7% vs. 32.1%, p=0.073; 6.6% vs. 6.2%, p=0.732). C. freundii showed a significant increase from period 1 to period 2 (1.7% vs. 13.2%, p=0.000). In both time periods, imipenem was the antimicrobial agent showing the highest rate of susceptibility (93.3% vs. 93.9%, p=0.783). Higher prevalence of ESBL-producing E. coli and C. freundii was observed in the hospital-acquired cholangitis group (52.1% vs. 31.2%, p=0.000; 15.9% vs. 7.3%, p=0.001).
  
  
  CONCLUSIONS
  The most common causative pathogen of acute cholangitis was ESBL-producing E. coli. Prevalence of C. freundii increased over the time period. Imipenem should be reserved as an alternative for resistant pathogens.
authors.affiliation: Department of Internal Medicine, Catholic University of Daegu School of Medicine, Duryugongwon-ro 17-gil, Nam-gu, Daegu 705-718, Korea.
authors.forename: Jeong Seok
authors.initials: JS
authors.lastname: Kwon
authors.forename: Jimin
authors.initials: J
authors.lastname: Han
authors.forename: Tae Won
authors.initials: TW
authors.lastname: Kim
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Oh
authors.forename: Hyun Hee
authors.initials: HH
authors.lastname: Kwon
authors.forename: Jin Tae
authors.initials: JT
authors.lastname: Jung
authors.forename: Joong Goo
authors.initials: JG
authors.lastname: Kwon
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Kim
authors.forename: Ho Gak
authors.initials: HG
authors.lastname: Kim
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002761:Cholangitis / Q000175:diagnosis / Q000382:microbiology*; D016971:Citrobacter freundii / Q000187:drug effects / Q000302:isolation & purification; D017714:Community-Acquired Infections / Q000382:microbiology; D003428:Cross Infection / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification; D005260:Female; D006801:Humans; D015378:Imipenem / Q000494:pharmacology; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D015378:Imipenem; D001618:beta-Lactamases