Antimicrobial Breakpoints for Gram-Negative Aerobes

Monte Carlo pharmacokinetic-pharmacodynamic modeling suggests that CLSI breakpoints may be set too high for some antibiotic-organism combinations, especially those involving Pseudomonas aeruginosa and Acinetobacter baumannii.

Monte Carlo simulations are used to determine the probability of attaining prespecified pharmacokinetic-pharmacodynamic (PK-PD) targets. Researchers in Texas recently performed such simulations to evaluate the current susceptibility breakpoints for 13 antimicrobials (21 dosing regimens) against Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter baumannii.

Analysis of percent PK-PD target attainment for dosing regimens when MICs equaled Clinical and Laboratory Standards Institute (CLSI) breakpoints revealed the need for aggressive cephalosporin dosing (e.g., cefepime, 2 g every 8 hours). Meropenem and imipenem had higher percent target attainment than did ertapenem; aminoglycosides dosed at 5 mg/kg every 24 hours produced only 20% …

Reviewing Author

Lynn L. Estes, PharmD

Disclosures

Editorial boardsMayo Clinic Antimicrobial Therapy Quick Guide

Lynn L. Estes, PharmD

Disclosures

Editorial boardsMayo Clinic Antimicrobial Therapy Quick Guide