Study Isolates.

Study isolates (plus WC-31, which was isolated from a patient on Hospital Day 1 after transfer from an outside hospital). Legend WC = Weill Cornell; PT = Patient age and gender; Date: All dates are from 2008; Floor: Each letter represents a different hospital floor; Antimicrobial susceptibility to the various agents was determined following CLSI guidelines, or the Mean Inhibitory Concentration is reported directly for polymyxin B and tigecycline (µg/mL): A/S: ampicillin-sulbactam, Carb: imipenem or meropenem; Cef: cefepime; Gent; gentamicin; Amik: amikacin; S/T: sulfamethoxazole-trimethoprim; Levo: levofloxacin; PM: polymyxin B; Tig: tigecycline; Source: Resp = respiratory. Susceptibility interpretation based on 2008 CLSI cutoff points.