Study Objective. To evaluate the impact of a shortage of piperacillintazobactam in the United States in 2002 on antimicrobial prescribing and associated rates of vancomycin-resistant enterococci (VRE) and Clostridium difficile infections.
Design. Retrospective chart review.
Setting. University-affiliated medical center.
Measurements and Main Results. Microbiologic reports, patient demographics, and antimicrobial utilization were evaluated for patients admitted 6 months before the shortage (March 1-August 31, 2001) and for 6 months during the shortage (March 1-August 31, 2002). Significant increases in usage of alternative β-lactamase inhibitor combinations, cefepime, levofloxacin, vancomycin, clindamycin, and metronidazole were observed during the shortage; in contrast, a significant decrease in the use of ceftriaxone took place. No change in the rate of VRE infection was observed from before to during the piperacillin-tazobactam shortage. However, a paradoxical 47% decrease in the rate of C. difficile colitis was documented during the shortage. Subsequent multivariate analyses suggested the reduced use of ceftriaxone and increased use of levofloxacin, but not the reduced use of piperacillin-tazobactam, correlated with the decreased rate of C. difficile infections.
Conclusion. The piperacillin-tazobactam shortage was associated with significant changes in antimicrobial prescribing, which resulted in a significant reduction in the rate of C. difficile but not VRE infections.