The Influence of Hospital Antimicrobial Use on Carbapenem Non-Susceptible Enterobacterales Incidence Rates According to Their Mechanism of Resistance: A Time-Series Analysis.

STRUCTURED SUMMARY Background Carbapenem non-susceptible Enterobacterales (CNSE) can be broadly divided into those that produce carbapenemases (carbapenemase-producing Enterobacterales [CPE]), and those that harbor other mechanisms of resistance (non-carbapenemase-producing CNSE [NCP-CNSE]). Aim To determine the predictors of CNSE nosocomial incidence rates according to their mechanism of resistance. Methods We conducted a time series analysis (Jul/2013 to Dec/2018) to evaluate the relationship in time between hospital antibiotic use and the percentage of adherence to hand hygiene with the CNSE rates. Findings We identified 20,641 non-duplicated Enterobacterales isolates, 2.2% were CNSE. Of them, 48.1% and 51.9% were CPE and NCP-CNSE, respectively. 78.3% of the CPE possessed a blaOXA-232 gene. We identified a transfer function model for CNSE, CPE, and OXA-232 CPE that explained 20.8%, 19.3%, and 24.2% of their variation, respectively. According to the CNSE and CPE models, an increase in piperacillin-tazobactam (TZP) use of 1 defined daily doses (DDD) per 100 hospital patient-days (HPD), would lead to an increase of 0.69 and 0.49 CNSE and CPE cases per 10,000 HPD, respectively. The OXA-232 CPE model estimates that an increase of 1 DDD/100 HPD of TZP use would lead to an increase of 0.43 OXA-232 CPE cases per 10,000 HPD. We could not identify a transfer function model for NCP-CNSE and we did not find a relationship between the adherence to hand-hygiene and the CNSE rates. Conclusion The use of TZP is related in time with the CPE nosocomial rates, mostly explained by its effect on OXA-232 CPE.