title: Risk factors for mortality and impact of broad-spectrum cephalosporin resistance on outcome in bacteraemic intra-abdominal infections caused by Gram-negative bacilli.
abstract: BACKGROUND
  Although several studies have evaluated the association of antimicrobial resistance and mortality in patients with Gram-negative bacteraemia, little is known regarding the impact of antimicrobial resistance on outcome in patients with intra-abdominal infections caused by Gram-negative bacilli (GNB). This study was performed to evaluate the impact of broad-spectrum cephalosporin resistance on outcome in patients with intra-abdominal infections caused by GNB.
  
  
  METHODS
  Data on 365 patients with bacteraemic intra-abdominal infections caused by GNB were obtained from the database of a nationwide surveillance for bacteraemia, and analyzed.
  
  
  RESULTS
  Seventy-one of the 365 patients (19.5%) harboured broad-spectrum cephalosporin-resistant infections. When compared with patients with susceptible infections, the group of patients with resistant infections had a lower treatment success rate at 7 days after the initiation of antimicrobial therapy (73.2% vs 85.0%, p = 0.023). However, the 30-day mortality rate for the resistant group was not significantly higher than for the susceptible group (16.9% vs 10.2%, p = 0.112). Multivariable analysis showed that severe sepsis was the most important risk factor associated with mortality (odds ratio 4.91, 95% confidence interval 2.26-10.63), along with underlying liver disease, nosocomial acquisition, underlying solid tumour, and higher Pitt bacteraemia score (all p < 0.05). Antimicrobial resistance and inappropriate initial antimicrobial therapy were not found to be associated with mortality.
  
  
  CONCLUSIONS
  Our data suggest that antimicrobial resistance and inappropriate initial antimicrobial therapy may not be significant determinants for the prognosis in intra-abdominal infections caused by GNB, for which drainage or decompression procedures of intra-abdominal sources are often necessary.
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Cheol-In
authors.initials: CI
authors.lastname: Kang
authors.forename: Doo Ryeon
authors.initials: DR
authors.lastname: Chung
authors.forename: Kwan Soo
authors.initials: KS
authors.lastname: Ko
authors.forename: Kyong Ran
authors.initials: KR
authors.lastname: Peck
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Song
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000150:complications / Q000382:microbiology / Q000401:mortality*; D018550:Cephalosporin Resistance; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010538:Peritonitis / Q000150:complications / Q000382:microbiology / Q000401:mortality*; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents