title: The efficacy of non-carbapenem antibiotics for the treatment of community-onset acute pyelonephritis due to extended-spectrum β-lactamase-producing Escherichia coli.
abstract: OBJECTIVE
  Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli has become an important cause of community-onset urinary tract infections. We aimed to evaluate the efficacy of non-carbapenem antibiotics for acute pyelonephritis (APN) due to ESBL-producing E. coli.
  
  
  METHODS
  We conducted a retrospective cohort study of patients with community-onset APN due to ESBL-producing E. coli at a single centre in Korea from 2007 to 2013. Outcomes included both microbiological and clinical failure. To adjust for non-random assignment of antibiotics, the propensity score method of inverse probability of treatment weighting and a multivariable analysis using Cox proportional hazards modelling were employed to estimate the efficacy of non-carbapenem antibiotics as compared with carbapenems.
  
  
  RESULTS
  Of 152 eligible patients, 85 (55.9%) received carbapenems and 67 (44.1%) received non-carbapenems. Non-carbapenem antibiotics used in this cohort included aminoglycosides (n = 30), β-lactam/β-lactamase inhibitors (n = 13), fluoroquinolones (n = 12) and trimethoprim/sulfamethoxazole (n = 5). Microbiological failure was observed in 16 patients receiving carbapenems (16/83, 19.3%) versus 4 patients receiving non-carbapenem (4/67, 6.0%). After weighting, the risk of microbiological failure was similar between the two groups [weighted hazard ratio (HR) 0.99; 95% CI 0.31-3.19]. In a multivariable regression analysis combined with weights, the estimate did not change (weighted adjusted HR 0.96; 95% CI 0.41-2.27). The clinical failure rate was also similar in the two groups (weighted HR 1.05; 95% CI 0.24-4.62).
  
  
  CONCLUSIONS
  These results suggest that non-carbapenem antibiotics were as effective as carbapenems as definitive therapy for treating community-onset APN caused by ESBL-producing E. coli if they are active in vitro.
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea zenithbrain@gmail.com.
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Park
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Su-Mi
authors.initials: SM
authors.lastname: Choi
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Yoon Kyung
authors.initials: YK
authors.lastname: Chang
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Dong-Gun
authors.initials: DG
authors.lastname: Lee
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Sung-Yeon
authors.initials: SY
authors.lastname: Cho
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Hyo-Jin
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Jung-Hyun
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Jin-Hong
authors.initials: JH
authors.lastname: Yoo
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections; D015897:Comorbidity; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology* / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011704:Pyelonephritis / Q000188:drug therapy* / Q000382:microbiology*; D012189:Retrospective Studies; D012307:Risk Factors; D017211:Treatment Failure; D016896:Treatment Outcome; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases
keywords: alternative therapy; antibiotic resistance; urinary tract infections