Restriction of cephalosporins do not alter the burden of cephalosporin resistant Klebsiella pneumoniae and Escherichia coli in a surgical ICU
Abstract number: O402
Meyer E., Lapatschek M., Bechthold A., Schwarzkopf G., Monnet D., Gastmeier P., Schwab F.
Objective: To test whether a reduction of third-generation cephalosporin (3GC)use has a sustainable positive impact on the high endemic prevalence of 3GC-resistant K. pneumoniae and E. coli in a surgical intensive care unit (ICU).
Intervention: Switch from 3GC to piperacillin in combination with a b-lactamase-inhibitor as standard therapy for peritonitis and other intraabominal infections in 7/2004.
Methods: Segmented regression analysis of interrupted time series was used to analyse antibiotic consumption and resistance data 30 months before and 30 after the intervention. Antimicrobial usage density (AD) was expressed as daily defined doses (DDD) and normalised per 1000 patient-days. The proportion of resistant isolates (RP) is calculated by dividing the number of resistant isolates by the total number of the isolates of this species tested against this antibiotic multiplied by 100. The resistance densities (RD) are expressed as the number of resistant isolates of a species/1000 pd.
Results: The intervention was associated with a significant and sustainable decrease in the use of 3GC. Use decreased from 178.9 before to 68.7 DDD/1000 pd. The intervention resulted in a mean estimated reduction of total antibiotic use of -375.0 DDD/1000 pd, which is equivalent to a 27% reduction. Total antibiotic use showed no significant month to month change before and after the intervention. Piperacillin and piperacillin/tazobactam showed a significant increase in level of 64.4 DDD/1000 pd and continued to increase by 2.3 DDD/1000 pd per month after the intervention.
The intervention was not associated with a significant quarterly change in the RD of K. pneumoniae and E. coli resistant to 3GC. In contrast, the reduced use of 3GC and the switch to piperacillin was followed by a continuous increase in the RD of E. coli resistant to piperacillin by 0.5 per 1000 pd per quarter and by a continuous decrease of P. aeruginosa resistant to piperacillin of 0.1 per quarter.
Conclusion: We conclude that concentratiing on the reduction of 3rd generation cephalosporins is not necessarily followed by a positive impact on the resistance situation in the ICU setting. Replacement with piperacillin with b-lactamase inhibitor might likewise provide a selection pressure on 3GC-resistant E. coli and K. pneumoniae. To improve resistance it might not be sufficient to restrict interventions to a risk area, rather, it may be essential to include the whole hospital and even the community.
|Session name:||18th European Congress of Clinical Microbiology and Infectious Diseases|
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