In this episode, I’ll discuss the suppression of antimicrobial susceptibility results.
When a hospital microbiology laboratory performs antimicrobial susceptibility testing using microdilution or disk diffusion methods, not all of the results are presented to clinicians in the medical record. Some of the data is ‘suppressed’ meaning the micro lab has the data but it is not forward-facing in the medical record.
There are several reasons why this is routinely done for example:
The antimicrobial is not on the hospital’s formulary
The antimicrobial is more expensive than sensitive agents (for example tobramycin/amikacin data is usually suppressed in gentamicin is susceptible)
There is no need to report a broad-spectrum agent when a narrower one is sensitive (no need to report cefepime if sensitive to ceftriaxone)
Usually, there is no need to access this suppressed data however at least 2 scenarios may occur that would lead a clinician to want to access this data for example:
The patient has more than one infection and you are trying to find a single antibiotic to cover all organisms
The patient has allergies or intolerances that you need to work around
When these scenarios occur, accessing the suppressed data is easy – just call your microbiology lab and ask for it.
And, if you are going to make a clinical decision based on the suppressed data, tell your lab so they can ‘release’ the data into the medical record where it can be viewed to justify your decision-making.
Can you think of another reason you would need to access suppressed susceptibility data? Let me know in the comments below.
Members of my Hospital Pharmacy Academy have access to practical training on antimicrobial susceptibility interpretation, along with over 200 practical trainings and other resources to help in your practice. To get immediate access, go to pharmacyjoe.com/academy.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.
Another scenario I call micro lab for is with ED culture results for a pt discharged on an agent for which sensitivities are not reported
Definitely. We use this option a lot for E faecalis. We suppress quinolones as we don’t want them using this as first line even if sensitive (one could argue that one of the reasons above would cover this as well.)