title: Clinical factors associated with acquisition of resistance to levofloxacin in Stenotrophomonas maltophilia.
abstract: OBJECTIVE
  Fluoroquinolones, rapidly gaining prominence in treatment of Stenotrophomonas maltophilia (SMP), are noted for their potency and tolerability. However, SMP may rapidly acquire resistance to fluoroquinolones. We evaluated associations of clinical factors with acquisition of levofloxacin resistance (LFr) in SMP.
  
  
  METHODS
  Our retrospective cohort study was based on patient data collected between January 2008 and June 2010. Through screening of 1275 patients, we identified 122 patients with data for SMP antibiotic susceptibility testing in ≥3 serial SMP isolates.
  
  
  RESULTS
  We assigned the 122 patients to either the SS group (n=54) in which levofloxacin susceptibility was maintained or the SR group (n=31) in which susceptible SMP acquired resistance. In multivariate regression analysis, exposure to levofloxacin for more than 3 weeks [odds ratio (OR) 15.39, 95% confidential interval (CI) 3.08-76.93, p=0.001] and co-infection or co-colonization with Klebsiella pneumoniae resistant to levofloxacin (OR 4.85, 95% CI 1.16-20.24, p=0.030) were independently associated with LFr acquisition in SMP.
  
  
  CONCLUSIONS
  Acquisition of LFr during serial sampling of SMP was related to the levofloxacin exposure.
authors: Department of Infectious Disease, Inha University Hospital, Incheon, Korea.
authors: Ji Hyeon
authors: JH
authors: Baek
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Chang Oh
authors: CO
authors: Kim
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Su Jin
authors: SJ
authors: Jeong
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Nam Soo
authors: NS
authors: Ku
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea. shhan74@yuhs.ac.
authors: Sang Hoon
authors: SH
authors: Han
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Jun Yong
authors: JY
authors: Choi
authors: Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea.
authors: Dongeun
authors: D
authors: Yong
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Young Goo
authors: YG
authors: Song
authors: Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea.
authors: Kyungwon
authors: K
authors: Lee
authors: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: June Myung
authors: JM
authors: Kim
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D024841:Fluoroquinolones / Q000494:pharmacology / Q000627:therapeutic use; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy; D006801:Humans; D064704:Levofloxacin / Q000494:pharmacology* / Q000627:therapeutic use*; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012189:Retrospective Studies; D020615:Stenotrophomonas maltophilia / Q000187:drug effects / Q000472:pathogenicity*
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D064704:Levofloxacin
keywords: Stenotrophomonas maltophilia; drug resistance; fluoroquinolones; levofloxacin