title: Microbiology of choledochal bile in patients with choledocholithiasis admitted to a tertiary hospital.
abstract: OBJECTIVE
  The present study was designed to investigate the microbiology of choledochal bile of patients with cholangitis and choledocholithiasis.
  
  
  METHODS
  We identified and determined the antimicrobial susceptibility of bacteria isolated in the bile of patients with cholangitis and choledocholithiasis diagnosed by endoscopic retrograde cholangiopancreatography (ERCP).
  
  
  RESULTS
  Nineteen (82.6%) of 23 patients with choledocholithiasis had positive bile cultures. A single agent was detected in 11 patients (57.9%), while a mixed growth, with pathogens ranging from two to three species, were seen in eight patients (42.1%). Patients with clinical manifestations of cholangitis had significantly higher counts of colonies per mL of bile (> 105 cfu/mL). The predominant Gram-negative aerobic bacteria isolated were Escherichia coli (9, 31.0%), Klebsiella pneumoniae (5, 17.2%), Enterobacter cloacae (2, 6.9%), Pantoea agglomerans (1, 3.4%), and Pseudomonas aeruginosa (1, 3.4%). The predominant Gram-positive bacteria were Enterococcus faecalis (5, 17.2%) and Streptococcus sp. (5, 17.2%). Bacteroides fragilis was isolated in one patient with mixed growth. All Gram-positive bacteria isolated in bile were sensitive to ampicillin, and all Gram-negative bacteria isolated were sensitive to gentamicin with a minimum inhibitory concentration (CIM90) ranging from 0.5 to 1.0- micro g/mL. Gram-negative bacteria were also sensitive to imipenem, fluorquinolones, second and third generation cephalosporins. Although all five isolates of E. faecalis were sensitive to ampicillin, two of five (40%) E. faecalis isolates demonstrated high levels of resistance to gentamicin.
  
  
  CONCLUSIONS
  E. coli, K. pneumoniae, E. faecalis and Streptoccocus sp. were the most common bacteria isolated in the bile of patients with cholangitis and choledocholithiasis, which were sensitive to a simple therapeutic regimen, such as the combination of ampicilin and gentamicin.
authors.affiliation: Gastroenterology Section, Porto Alegre Clinical Hospital, Faculty of Medicine, Federal University of Rio Grande do Sul, Brazil.
authors.forename: Cristina
authors.initials: C
authors.lastname: Flores
authors.forename: Ismael
authors.initials: I
authors.lastname: Maguilnik
authors.forename: Everton
authors.initials: E
authors.lastname: Hadlich
authors.forename: Luciano Z
authors.initials: LZ
authors.lastname: Goldani
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000667:Ampicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001938:Brazil; D002511:Cephalosporins / Q000627:therapeutic use; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003135:Common Bile Duct / Q000000981:diagnostic imaging / Q000382:microbiology* / Q000473:pathology*; D004198:Disease Susceptibility / Q000175:diagnosis / Q000382:microbiology / Q000628:therapy; D005260:Female; D042882:Gallstones / Q000175:diagnosis / Q000382:microbiology* / Q000628:therapy*; D005839:Gentamicins / Q000627:therapeutic use; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis / Q000382:microbiology / Q000628:therapy; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000382:microbiology / Q000628:therapy; D006801:Humans; D015378:Imipenem / Q000627:therapeutic use; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D010343:Patient Admission; D010406:Penicillins / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D005839:Gentamicins; D010406:Penicillins; D015378:Imipenem; D000667:Ampicillin