TABLE 2.

Definitions of resistance in Pseudomonas aeruginosa

Resistance phenotype	Definition
Carbapenem-resistant	Any isolate that tested either (I) or (R) to at least 1 of these: imipenem, meropenem, or doripenem
Extended-spectrum cephalosporin-resistant	Any isolate that tested (R) to at least 1 of these: cefepime or ceftazidime
Piperacillin-tazobactam-resistant	Any isolate that tested (R) to at least 1 of these: piperacillin, piperacillin-tazobactam
Fluoroquinolone-resistant	Any isolate that tested (R) to at least 1 of these: ciprofloxacin, levofloxacin
Aminoglycoside-resistant	Any isolate that tested (R) to at least 1 of these: amikacin, gentamicin, tobramycin
Multidrug-resistant (MDR)	Any isolate that tested either (I) or (R) to at least 1 drug in at least 3 of these categories: Extended-spectrum cephalosporins (cefepime, ceftazidime) Fluoroquinolones (ciprofloxacin, levofloxacin) Aminoglycosides (amikacin, gentamicin, tobramycin) Carbapenems (imipenem, meropenem, doripenem) Piperacillin Group (piperacillin, piperacillin-tazobactam)