24 - 48 hours after isolation of specific organism to be tested or isolate received
Test Updated:
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Test Overview
The susceptibility methodology is dependent on the site of infection and/or the organism. In most cases, an MIC will be performed. Disk diffusion (Kirby-Bauer) will be performed on organisms such as mucoid pseudomonas, stenotrophomonas, Pseudomonas aeruginosa from CF patients, and if susceptibility is requested for additional drugs not available using the MIC methodology. Extended spectrum beta-Lactamase testing will be performed on Gram negative bacteria when indicated by susceptibility pattern. Beta-Lactamase testing (enzyme detection) will be performed on Gram positive bacteria when indicated by susceptibility pattern.
To determine susceptibility of a given organism to a panel of antimicrobic agents.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
For all cultures, susceptibility testing is performed automatically on potentially pathogenic organism(s) at an additional charge unless specifically declined. To request susceptibility testing using antibiotics not normally tested, call directly to the Susceptibility Testing area (936-6831). Organisms will be held up to 7 days from the date specimen was received.
For all cultures, susceptibility testing is performed automatically on potentially pathogenic organism(s) at an additional charge unless specifically declined. To request susceptibility testing using antibiotics not normally tested, call the MLabs Client Services Center. Organisms will be held up to 7 days from the date specimen was received. For testing on actively growing organisms: 1) Aerobic Bacteria: Swab organism from pure culture and send swab in aerobic transport tube. Do not send plate. Transport at room temperature. (Swabs sent in aerobic transport do not require two-pouch SAF-T-PAK system.) 2) Anaerobic Bacteria: Place actively growing organism on anaerobic plate in an anaerobic transport bag. Place inside clear, liquid tight SAF-T-PAK bag and seal tape liner. Place sealed bag and requisition inside white biohazard SAF-T-PAK envelope and seal. Transport at room temperature.