Cefoxitin Minimum Inhibitory Concentration (MIC) by Broth Microdilution
This test measures how much of the antibiotic cefoxitin is needed to stop bacterial growth, helping doctors choose the best treatment for infections.
["Your doctor may use this test to pick the right antibiotic for bacterial infections."]
Key facts at a glance
- LOINC
- 25220-5
- Short code
- CEFOX-SGM
- Synonyms
- cefOXitin Islt Slgr Mcbct AB 30.0
- Category
- chemistry
- Sample
- serum
- Container
- Sterile, leak-proof container; specify culture transport medium for mycobacterial specimens. Avoid formalin fixation.
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- method-for-slow-growing-mycobacteria-antibiotic-concentration-at-ug-ml
- CPT
- 87181
- SNOMED
- 385719001
- Specimen volume
- Variable by specimen type: sputum 5-10 mL, BAL 10-30 mL, tissue as collected, blood 5-10 mL in SPS or ACD tube, CSF 1-2 mL minimum, urine 20-50 mL first morning void, sterile body fluids as available.
- Stability
- Refrigerate at 2-8°C; transport to laboratory within 24 hours of collection. For delayed processing, specimens may be refrigerated up to 7 days depending on specimen type. Do not freeze.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 168–720 hours
- Order
- routine
What This Test Measures
The test uses a series of diluted cefoxitin solutions in a broth medium to determine the lowest concentration of the antibiotic that prevents bacterial growth. This helps identify the effectiveness of cefoxitin against specific bacteria in your sample.
Why It’s Done
Your healthcare provider may order this test if you have a suspected bacterial infection that might respond to cefoxitin, such as skin, joint, or bone infections. It’s often used when antibiotics are needed but the type of bacteria causing the infection isn’t known yet.
How the Test Works
A small sample of your blood or other bodily fluid is mixed with cefoxitin in a controlled environment. Bacteria are added to each well of a microdilution plate, and the test checks which concentration of cefoxitin stops bacterial growth after a set time.
What to Expect Before the Test
No special preparation is needed unless your doctor instructs you differently. You may be asked to avoid certain medications or foods that could affect test results, but this depends on the specific instructions given to you.
Reference range
Interpretive criteria: Susceptible (S), Intermediate (I), or Resistant (R) based on CLSI M24 guidelines for slow-growing mycobacteria. No quantitative reference range applies; results are reported categorically.N/A
No special patient preparation required. Specimen should be collected prior to initiation of anti-mycobacterial therapy when possible. For follow-up testing, note current medication regimen.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Cefoxitin MIC
Frequently asked questions
How does cefoxitin MIC help doctors treat infections?
What if my test shows cefoxitin is effective but I’m still not feeling better?
Can I take cefoxitin if I’m allergic to other antibiotics?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy