Evaluating empiric treatment options for secondary peritonitis using pharmacodynamic profiling.
Kathryn J Eagye1, Joseph L Kuti, David P Nicolau
1Center for Anti-Infective Research Development, Hartford Hospital, Hartford, CT 06102, USA.
Surgical Infections
|April 18, 2007
Summary
Carbapenems and piperacillin/tazobactam offer optimal antibiotic exposure for secondary peritonitis pathogens, outperforming fluoroquinolones and ceftriaxone due to rising resistance. Cefepime and ceftazidime are also viable options when combined with metronidazole.
Area of Science:
- Pharmacology and Infectious Diseases
- Antimicrobial Resistance
- Clinical Microbiology
Background:
- Empiric antibiotic selection for secondary peritonitis is complicated by increasing resistance in aerobic gram-negative bacilli.
- Optimizing pharmacodynamic exposure is crucial for effective treatment of secondary peritonitis.
Purpose of the Study:
- To predict the pharmacodynamic exposure of common antimicrobial regimens against aerobic bacteria implicated in secondary peritonitis.
- To evaluate antimicrobial efficacy considering current national antibiotic resistance trends.
Main Methods:
- Monte Carlo simulations were employed to model pharmacodynamic endpoints.
- Cumulative fraction of response (CFR) was compared for various antibiotics against secondary peritonitis isolates.
- Minimum inhibitory concentration (MIC) data from the 2004 MYSTIC database and pharmacokinetic parameters were utilized.
Main Results:
- Imipenem-cilastatin, meropenem, ertapenem, piperacillin/tazobactam, ceftazidime, and cefepime demonstrated high predicted CFRs.
- Ceftriaxone, ciprofloxacin, and levofloxacin showed lower CFRs (<82%), indicating reduced efficacy.
Conclusions:
- Monotherapy with carbapenems or piperacillin/tazobactam provides optimal exposure for common secondary peritonitis pathogens.
- Cefepime or ceftazidime, when combined with metronidazole, are acceptable alternatives.
- Fluoroquinolones and ceftriaxone appear inferior due to emerging resistance, particularly in E. coli.
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