title: Fluoroquinolones and the risk for methicillin-resistant Staphylococcus aureus in hospitalized patients.
abstract: To determine whether fluoroquinolone exposure is a risk factor for the isolation of Staphylococcus aureus and whether the effect is different for methicillin-resistant S. aureus (MRSA) versus methicillin--susceptible S. aureus (MSSA), we studied two case groups. The first case group included 222 patients with nosocomially acquired MRSA. The second case group included 163 patients with nosocomially acquired MSSA. A total of 343 patients admitted concurrently served as controls. Outcome measures were the adjusted odds ratio (OR) for isolation of MRSA and MSSA after fluoroquinolone exposure. Exposure to both levofloxacin (OR 5.4; p <0.0001) and ciprofloxacin (OR 2.2; p < 0.003) was associated with isolation of MRSA but not MSSA. After adjustment for multiple variables, both drugs remained risk factors for MRSA (levofloxacin OR 3.4; p <0.0001; ciprofloxacin OR 2.5; p = 0.005) but not MSSA. Exposure to levofloxacin or ciprofloxacin is a significant risk factor for the isolation of MRSA, but not MSSA.
authors.affiliation: Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA. sgweber@medicine.bsd.uchicago.edu
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Weber
authors.forename: Howard S
authors.initials: HS
authors.lastname: Gold
authors.forename: David C
authors.initials: DC
authors.lastname: Hooper
authors.forename: A W
authors.initials: AW
authors.lastname: Karchmer
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Carmeli
mesh_terms: D000368:Aged; D000890:Anti-Infective Agents / Q000494:pharmacology*; D016022:Case-Control Studies; D002939:Ciprofloxacin / Q000494:pharmacology*; D003428:Cross Infection / Q000209:etiology*; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D008297:Male; D016106:Methicillin Resistance / Q000187:drug effects*; D008875:Middle Aged; D012307:Risk Factors; D013211:Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification*
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D002939:Ciprofloxacin