In vitro activity of piperacillin/tazobactam versus other broad-spectrum antibiotics against nosocomial gram-negative pathogens isolated from burn patients.
Burn patients are at high risk for nosocomial infections due to multiresistant bacteria, a large proportion of which are gram-negative. Tazobactam, a potent inhibitor of beta-lactamases, extends the spectrum of piperacillin to include many beta-lactamase producing bacteria. Consequently, it was decided to evaluate the activity of piperacillin/tazobactam in comparison with that of eight other antibiotics that are usually used for therapy against gram-negative bacterial infections in our burn unit. All consecutive gram-negative isolates from wounds, blood, respiratory tract, urine etc. from burn patients considered to be clinically significant were tested for their susceptibility to piperacillin/tazobactam, piperacillin, ceftazidime, cefotaxime, ceftriaxone, ciprofloxacin, gentamicin, amikacin and imipenem, determined by disk diffusion test. The zone inhibition was interpreted according to NCCLS recommendations. A total of 948 strains, isolated during the period of July, 1994 to September, 1995, made up of Pseudomonas spp (326), Acinetobacter spp (268) and Enterobacteriaceae (354), were tested. Overall piperacillin/tazobactam showed superior activity over the other antibiotics except for imipenem. Of the 948 isolates, 87% were susceptible to the combination, 56% to the three third generation cephalosporins, 69% to ciprofloxacin, 59% to the aminoglycosides and 97% to imipenem. Piperacillin/tazobactam showed strikingly superior activity over piperacillin alone against Acinetobacter spp followed by Enterobacteriaceae and the least against Pseudomonas. The emergence of Acinetobacter spp as a dominant gram-negative pathogen in burn patients and its high level of resistance against most of the antibiotics tested except piperacillin/tazobactam (87%) and imipenem (100%) were significant in light of the epidemiology of burn infections and treatment. This study suggests that piperacillin/tazobactam holds good promise against gram-negative infections in burn patients.
Mokaddas
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Department of Microbiology, Ibn Sina Hospital, Kuwait.
Rotimi
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VO
Sanyal
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SC
D002056:Burns / Q000382:microbiology*; D003428:Cross Infection / Q000382:microbiology*; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests; D010397:Penicillanic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D010878:Piperacillin / Q000494:pharmacology; D000077725:Piperacillin, Tazobactam Drug Combination
D000077725:Piperacillin, Tazobactam Drug Combination; D010397:Penicillanic Acid; D010878:Piperacillin