Susceptibility surveillance among gram-negative bacilli at a cancer center

We conducted a survey of susceptibility among 758 gram-negative bacilli (GN B; collected from cancer patients over a 3-month period) to commonly used a ntibiotics. The overall resistance among GNB was least for piperacillin/taz obactam and meropenem (5 and 6%, respectively) followed by cefepime (8%), i mipenem (9%), amikacin (12%), ofloxacin (13%), ciprofloxacin, ceftazidime a nd ticarcillin/clavulanate (14% each), aztreonam (18%) and tobramycin (24%) . In comparison to data on antibiotic resistance to ceftazidime, imipenem, ciprofloxacin and aztreonam in similar studies in 1985 and 1994, resistance has significantly increased to all four antibiotic classes. Based on our c urrent study, meropenem, cefepime, imipenem and piperacillin/tazobactam wou ld be the most appropriate choices in our institution for empiric therapy o f GNB infections in febrile neutropenic patients.