Phenotypic and Genotypic Characterization of Fecal Escherichia coli Isolates with Decreased Suscepti

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Phenotypic and Genotypic Characterization of
Fecal Escherichia coli Isolates with Decreased
Susceptibility to Fluoroquinolones Results from
a Large Hospital-Based Surveillance Initiative
Ebbing Lautenbach, MD, MPH 825 Blockley Hall, 423
Guardian Drive Philadelphia, PA 19104-6021
USA [phone] elautenb_at_cceb.med.upenn.edu
Ebbing Lautenbach, MD, MPH, MSCE Neil O.
Fishman, MD Joshua P. Metlay, MD, PhD Xiangqun
Mao, PhD Warren B. Bilker, PhD Pam Tolomeo,
MPH Irving Nachamkin, Dr PH, MPH University of
Pennsylvania School of Medicine

• 144 (96.6) isolates had a nalidixic acid MIC in
  the non-susceptible range (i.e., gt16 µg/ml).
• 59 (39.6) isolates showed organic solvent
  tolerance.
• The proportion of isolates demonstrating organic
  solvent tolerance varied significantly across
  study years 17/35 (48.6) in 2002, 31/65 (47.7)
  in 2003, and 11/49 (22.4) in 2004 (p0.01).