Bacterialeisdrugresmutisltspm
This test detects genetic mutations in bacteria that make them resistant to certain antibiotics, helping doctors choose the right treatment.
{"Detects genetic changes (mutations) in bacteria that cause antibiotic resistance","Helps guide treatment decisions for bacterial infections, especially tuberculosis","Uses a blood sample and advanced molecular technology to analyze bacterial DNA","Results help doctors select effective antibiotics and avoid treatments that won't work","Important for managing drug-resistant infections"}
Key facts at a glance
- LOINC
- 94064-3
- Short code
- TB-EIS-RES
- Synonyms
- Bacterial eis drug res mut Islt/Spm
- Category
- chemistry
- Sample
- serum
- Container
- Sterile, leak-proof, screw-capped container for clinical specimens (sputum, BAL fluid, or other respiratory samples); or mycobacterial culture isolate in appropriate transport medium for direct molecular testing
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- CPT
- 87556
- SNOMED
- 446080006
- Specimen volume
- Minimum 1-2 mL of clinical specimen (sputum, BAL, or other respiratory sample) or sufficient mycobacterial growth from culture isolate for nucleic acid extraction
- Stability
- Specimens should be transported to the laboratory promptly at 2-8°C. Refrigerate at 2-8°C for up to 7 days; freeze at -70°C or below for longer storage. DNA extracts are stable at -20°C for extended periods. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
What is this test?
The Bacterial eis Gene Drug Resistance Test is a molecular test that looks for specific genetic changes (mutations) in bacteria. The eis gene is found in certain bacteria, particularly Mycobacterium tuberculosis (the germ that causes tuberculosis). When this gene is mutated, it can make the bacteria resistant to certain antibiotics, especially aminoglycoside drugs like kanamycin, amikacin, and capreomycin, which are used to treat drug-resistant tuberculosis.
Why do I need this test?
Your doctor may order this test if you have a bacterial infection that is not responding to standard antibiotics, or if you have been diagnosed with tuberculosis. The test helps determine if your infection is caused by bacteria with drug-resistant mutations. This information is crucial for your doctor to prescribe the most effective medications for your specific infection.
How is the test done?
A healthcare professional will collect a blood sample from a vein in your arm. The sample is then sent to a laboratory where technicians use advanced molecular methods to analyze the bacterial DNA. The test looks specifically for mutations in the eis gene that are known to cause antibiotic resistance. Your results will indicate whether such mutations are present.
What do the results mean?
If the test detects mutations in the eis gene, it means your bacterial infection may be resistant to certain antibiotics (particularly kanamycin, amikacin, and capreomycin). Your doctor will use this information to choose different, more effective antibiotics. If no mutations are found, the bacteria may still be sensitive to these standard antibiotics.
Are there any risks?
The blood draw may cause slight pain, bruising, or dizziness in some people. These risks are minimal and temporary. The test itself has no direct risks as it only analyzes a blood sample.
Reference range
Not Applicable. This is a qualitative molecular test reporting the presence or absence of eis gene mutations associated with aminoglycoside resistance. Results are reported as 'Mutation Detected,' 'No Mutation Detected,' or 'Indeterminate'.N/A
No special patient preparation required. Specimen collection should follow standard infection control precautions for suspected tuberculosis cases. Collect specimen prior to initiation of anti-tuberculosis therapy when possible to optimize detection of resistance mutations.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings2
Frequently asked questions
How long does it take to get results?
Do I need to fast before this test?
Will this test hurt?
What happens if my test shows drug resistance?
Is this test only for tuberculosis?
Sources
- 1
- 2
- 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