Antimicrobial Stewardship: Antibiogram

Antibiograms are a compilation of antimicrobial susceptibility test results from cultures performed during a given time period. They generally focus on results for a selected group of organisms of interest. Laboratories within hospitals or reference laboratories produce antibiograms for use by clinicians to guide understanding of local resistance patterns.

Antibiograms are also useful for monitoring resistance patterns over time in a particular facility or a group of facilities.

Antibiograms generally require culture results for at least one year to have sufficient data. Smaller facilities may need longer time periods or more of a regional approach to achieve necessary data volumes. The organisms of interest will vary depending on the type of cultures analyzed by the lab and frequency of identification for the facility.

A petri dish with e-coli growing.

Antibiograms help to guide clinician selection for the best empiric antimicrobial therapy when cultures are pending, using the local trend as a proxy until more specific results are available. Health systems may also incorporate these results into their drug formulary options or as part of antimicrobial stewardship team polices to reinforce the use of antimicrobials that demonstrate less resistance. Utilizing this evidence-based approach is an important tool for antimicrobial stewardship teams both at the individual patient outcome level, as well as for the facility and geographic region.



Last Revised: August 31, 2021