title: Epidemiology of bloodstream infections in patients with acute myeloid leukemia undergoing levofloxacin prophylaxis.
abstract: BACKGROUND
  Infections are a common cause of morbidity and mortality in patients with acute myeloid leukemia (AML). The evidence for efficacy of antibiotic prophylaxis in reducing the mortality rates and the incidence of bacterial infections was also reported by a systematic review published by Cochrane in 2012. The objective of our study was to report the incidence and the etiology of bloodstream infections in patients with AML undergoing levofloxacin prophylaxis during neutropenic episodes.
  
  
  METHODS
  This was a retrospective study of patients with diagnosis of AML during 2001-2007.
  
  
  RESULTS
  A total of 81 patients were included in the study. Two hundred and ninetyone neutropenic episodes were studied, of which 181 were febrile. Bacteria isolated from blood cultures were mostly Gram-positives during the induction (80%) and Gram-negatives during the consolidation (72.4%) phases of chemotherapy. Resistance to ciprofloxacin was found in 78.9% of isolated E. coli and it was higher during consolidation and higher than the hospital rate. The production of extended spectrum betalactamases (ESBL) in E. coli strains was reported in 12.1%, below the reported hospital rate during the study period.
  
  
  CONCLUSIONS
  Regular microbiology surveillance is needed to better understand the impact of levofloxacin prophylaxis in neutropenic patients. Our study shows that Gram-positive bacteria are predominant during the induction phase of chemotherapy and Gram-negatives during the consolidation. The rate of fluoroquinolone resistance in the latter setting, even higher than the hospital rate, may suggest to reconsider levofloxacin prophylaxis.
authors.affiliation: Department of Medical Sciences, Infectious Diseases, Amedeo di Savoia Hospital, University of Turin, Corso Svizzera 164, 10149 Turin, Italy. francescogiuseppe.derosa@unito.it.
authors.forename: Francesco Giuseppe
authors.initials: FG
authors.lastname: De Rosa
authors.forename: Ilaria
authors.initials: I
authors.lastname: Motta
authors.forename: Ernesta
authors.initials: E
authors.lastname: Audisio
authors.forename: Chiara
authors.initials: C
authors.lastname: Frairia
authors.forename: Alessandro
authors.initials: A
authors.lastname: Busca
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Perri
authors.forename: Filippo
authors.initials: F
authors.lastname: Marmont
mesh_terms: D000328:Adult; D000368:Aged; D019072:Antibiotic Prophylaxis; D016470:Bacteremia / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology / Q000517:prevention & control*; D001419:Bacteria / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D001424:Bacterial Infections / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology / Q000517:prevention & control*; D002939:Ciprofloxacin / Q000627:therapeutic use; D005260:Female; D024841:Fluoroquinolones; D006801:Humans; D015994:Incidence; D015470:Leukemia, Myeloid, Acute / Q000150:complications*; D064704:Levofloxacin / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000150:complications*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D024841:Fluoroquinolones; D002939:Ciprofloxacin; D064704:Levofloxacin