Appropriate administration of tazobactam/piperacillin for urinary and genital tract infections based on antibiotic susceptibility testing: a single-center retrospective analysis

Abstract

Objective

Tazobactam/piperacillin (TAZ/PIPC) is a broad-spectrum antimicrobial agent. However, improper administration may contribute to antimicrobial resistance (AMR). The objectives of this study were to evaluate the appropriateness of TAZ/PIPC administration for UGTI based on antibiotic susceptibility testing and to elucidate the patients for whom alternative antibiotics can be utilized as the initial empiric therapy.

Methods

Patients diagnosed with UGTI at the University of Toyama Hospital between January 2022 and December 2024 who received TAZ/PIPC as initial empirical therapy were analyzed retrospectively. The appropriateness of alternative agents was determined by assessing bacterial culture and antimicrobial susceptibility results.

Results

Sixty-two UGTI episodes were analyzed. TAZ/PIPC utilization appeared appropriate in 91.9% of cases. Enterococcus faecalis and Pseudomonas aeruginosa were isolated more frequently in UGTI with devices or ileal urinary diversions compared to UGTI without devices. For patients with ileal urinary diversions or devices, the differences in the appropriateness rates of TAZ/PIPC versus CFPM, CTRX, and SBT/ABPC were higher than those for patients without devices. In patients without devices, the appropriateness rates of TAZ/PIPC, CFPM, CTRX, and SBT/ABPC were 96.7% (29/30), 86.7% (26/30), 83.3% (25/30), and 80.0% (24/30), respectively. Multivariate logistic regression analysis revealed that only the presence of an ileal urinary diversion, a urethral catheter, or a ureteral stent was a risk factor for the inappropriateness (p < 0.05) for CFPM, CTRX, and SBT/ABPC.

Conclusion

Based on antibiotic susceptibility testing, TAZ/PIPC may be considered for UGTI using devices or ileal urinary diversions. However, alternative antibiotics may be considered for UGTIs without indwelling devices.