Methicillin-Resistant Staphylococcus aureus (MRSA) or Vancomycin-Resistant Enterococcus Species
Identifies resistant bacteria that can cause difficult-to-treat infections and may require antibiotic treatment guided by laboratory susceptibility results.
A positive result means an infection-causing bacterium has resistance to an important antibiotic and treatment may need to be adjusted.
Key facts at a glance
- LOINC
- 54789-3
- Short code
- STAPHYLOCOCCUSAUREUSMETHICILLINRESISTANTORENTEROCOCCUSSPECIESVANCOMYCINRES
- Synonyms
- —
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Critical range
- 0.5 N/A – —
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- mdsv
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test detects methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus species, often called VRE. These bacteria can resist commonly used antibiotics, making infections harder to treat.
Why might I need this test?
Testing may be ordered when there is concern about a resistant infection, during outbreaks, or when screening is needed in certain healthcare settings. It can also help determine which antibiotics are likely to be effective.
How is the test performed?
A clinical specimen, such as blood, urine, a wound swab, or another sample, is collected and tested by the laboratory. The exact testing method depends on the specimen and the test ordered, and results may be based on culture or another validated method.
How do I prepare for the test?
No special preparation is usually required. Follow any instructions provided by your healthcare professional, particularly if the test involves collecting a urine or stool sample or if screening is being done before a procedure.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive result indicates that the tested sample contains MRSA or vancomycin-resistant Enterococcus. This may represent a true infection or colonization, depending on the specimen and clinical findings. Resistant infections may require different antibiotic choices and additional infection-control precautions, so results should be interpreted with the rest of the medical evaluation.
Short name
MRSA or VRE testing
Frequently asked questions
Does a positive result mean I have an infection?
Are MRSA and VRE the same thing?
Can resistant bacterial infections still be treated?
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 17, 2026. · Read our editorial policy