Effect of Stepwise Antimicrobial Stewardship for Carbapenems on Carbapenem Usage and the Rate of Resistance of Pseudomonas aeruginosa to Meropenem:

a Single-center Retrospective Study

Abstract

The aim of this report was to evaluate whether days of therapy (DOT), antimicrobial use density (AUD), and the rate of resistance of Pseudomonas aeruginosa to meropenem (the rate of resistance) change after stepwise execution of antimicrobial stewardship for carbapenems.

Since April 2012, antimicrobial stewardship for carbapenems has been performed by an infection control team comprising physicians and pharmacists specializing in infectious diseases. The stewardship included surveillance of all cases of carbapenem use since April 2012, intervention and feedback for cases of inappropriate carbapenem use since April 2013, and unification of carbapenems since November 2014. Surveillance implementation alone led to an increase in the rate of resistance, DOT, and AUD. However, the rate of resistance, DOT, and AUD decreased when surveillance implementation was combined with intervention and feedback. On the other hand, DOT and AUD decreased and the rate of resistance was unchanged upon combining these approaches and unification of carbapenems.

These results suggest that focus on implementation of surveillance would not be sufficient to ensure the appropriate use of carbapenems and that interventions and feedback regarding inappropriate carbapenem use would be important for promoting appropriate carbapenems use. Furthermore, these results suggest that unification of carbapenems does not negatively affect the rate of resistance.