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How fluoroquinolone preauthorization affects third- and fourth-generation cephalosporin use and resistance in a large
Adeniyi J Idigo1, Matthew L Brown2, Howard W Wiener1
1Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama.
Objective:
We observed an overall increase in the use of third- and fourth-generation cephalosporins after fluoroquinolone preauthorization was implemented. We examined the change in specific third- and fourth-generation cephalosporin use, and we sought to determine whether there was a consequent change in non-susceptibility of select Gram-negative bacterial isolates to these antibiotics.
Design:
Retrospective quasi-experimental study.
Setting:
Academic hospital.
Intervention:
Fluoroquinolone preauthorization was implemented in the hospital in October 2005. We used interrupted time series (ITS) Poisson regression models to examine trends in monthly rates of ceftriaxone, ceftazidime, and cefepime use and trends in yearly rates of nonsusceptible isolates (NSIs) of select Gram-negative bacteria before (1998-2004) and after (2006-2016) fluoroquinolone preauthorization was implemented.
Results:
Rates of use of ceftriaxone and cefepime increased after fluoroquinolone preauthorization was implemented (ceftriaxone RR, 1.002; 95% CI, 1.002-1.003; P < .0001; cefepime RR, 1.003; 95% CI, 1.001-1.004; P = .0006), but ceftazidime use continued to decline (RR, 0.991, 95% CI, 0.990-0.992; P < .0001). Rates of ceftazidime and cefepime NSIs of Pseudomonas aeruginosa (ceftazidime RR, 0.937; 95% CI, 0.910-0.965, P < .0001; cefepime RR, 0.937; 95% CI, 0.912-0.963; P < .0001) declined after fluoroquinolone preauthorization was implemented. Rates of ceftazidime and cefepime NSIs of Enterobacter cloacae (ceftazidime RR, 1.116; 95% CI, 1.078-1.154; P < .0001; cefepime RR, 1.198; 95% CI, 1.112-1.291; P < .0001) and cefepime NSI of Acinetobacter baumannii (RR, 1.169; 95% CI, 1.081-1.263; P < .0001) were increasing before fluoroquinolone preauthorization was implemented but became stable thereafter: E. cloacae (ceftazidime RR, 0.987; 95% CI, 0.948-1.028; P = .531; cefepime RR, 0.990; 95% CI, 0.962-1.018; P = .461) and A. baumannii (cefepime RR, 0.972; 95% CI, 0.939-1.006; P = .100).
Conclusions:
Fluoroquinolone preauthorization may increase use of unrestricted third- and fourth-generation cephalosporins; however, we did not observe increased antimicrobial resistance to these agents, especially among clinically important Gram-negative bacteria known for hospital-acquired infections.
Insights
Implementing fluoroquinolone preauthorization led to increased use of third- and fourth-generation cephalosporins. However, this did not result in higher antimicrobial resistance in key Gram-negative bacteria, suggesting a potential shift in antibiotic prescribing practices.
Area of Science:
- Antimicrobial stewardship
- Infectious disease epidemiology
- Clinical pharmacy
Background:
- Fluoroquinolone preauthorization is a strategy to control antibiotic use.
- Understanding the impact of such policies on the use of alternative antibiotics is crucial.
- The effect on antimicrobial resistance patterns, particularly for Gram-negative bacteria, requires investigation.
Purpose of the Study:
- To assess changes in the utilization of third- and fourth-generation cephalosporins following fluoroquinolone preauthorization.
- To determine if there was a subsequent change in the non-susceptibility rates of Gram-negative bacterial isolates to these cephalosporins.
Main Methods:
- A retrospective quasi-experimental study was conducted in an academic hospital.
- Interrupted time series (ITS) Poisson regression models analyzed monthly antibiotic use and yearly non-susceptible isolate (NSI) rates.
- Data spanned before (1998-2004) and after (2006-2016) the implementation of fluoroquinolone preauthorization.
Main Results:
- Ceftriaxone and cefepime use significantly increased post-preauthorization, while ceftazidime use declined.
- Non-susceptibility rates for ceftazidime and cefepime in Pseudomonas aeruginosa decreased.
- While initial increases in non-susceptibility were observed for Enterobacter cloacae and Acinetobacter baumannii, these rates stabilized after preauthorization.
Conclusions:
- Fluoroquinolone preauthorization may lead to increased use of alternative broad-spectrum antibiotics like cephalosporins.
- No significant increase in antimicrobial resistance to these cephalosporins was observed in key Gram-negative bacteria.
- This suggests a potential for successful antibiotic stewardship without compromising resistance profiles for hospital-acquired infections.
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