###1: Cerebrospinal Fluid B2 Transferrin Mass Concentration
###3: This test measures the amount of B2 transferrin in cerebrospinal fluid (CSF). It is mainly used to determine whether a fluid sample, such as fluid from the nose or ear, contains CSF.
["###4: Detecting B2 transferrin can help identify cerebrospinal fluid leaking from the nervous system into another body fluid."]
Key facts at a glance
- LOINC
- 53559-1
- Short code
- B2TRFCSF
- Synonyms
- B2 Transferrin CSF-mCnc
- Category
- chemistry
- Sample
- csf
- Container
- Sterile CSF collection tube or sterile leak-proof container; polypropylene preferred
- Units
- N/A
- Ref low
- 0
- Ref high
- 0
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Immunofixation Electrophoresis; Immunonephelometry; Western Blot
- CPT
- 86335
- SNOMED
- 104271009
- Specimen volume
- 0.5 to 1 mL of CSF or suspected CSF-containing fluid
- Stability
- Room temperature: 4 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days
- Hemolysis max
- 200
- TAT
- 4–72 hours
- Order
- routine
###5: What This Test Measures
###6: B2 transferrin is a form of transferrin that is produced in the central nervous system and is especially concentrated in CSF. The test detects this form in the submitted specimen.
###7: Why It Is Performed
###8: Clinicians may order this test when fluid is leaking from the nose, ear, or another area and the source is unclear. A positive result strongly supports the presence of CSF in the specimen.
###9: Sample Collection
###10: The laboratory may test a directly collected CSF sample or another fluid that could contain CSF. The specimen type and collection method can affect interpretation, so results should be reviewed with the healthcare provider who ordered the test.
###11: Understanding the Result
###11: A detectable result supports CSF as the source of the fluid. An undetectable result does not always rule out a leak, because the amount of fluid present, collection timing, and test methods can influence detection.
Reference range
Negative for beta-2 transferrin band. Beta-2 transferrin is normally absent in cerebrospinal fluid and indicates a CSF leak when detected in other body fluids.N/A
No special patient preparation is required. For suspected CSF rhinorrhea or otorrhea, collect the fluid specimen directly into a sterile container. Ensure the specimen is not contaminated with blood, tears, saliva, or nasal secretions.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
###13: B2 transferrin testing is clinically significant because it can help confirm a CSF leak, including leaks associated with head trauma, surgery, or other nervous-system disorders. The result should be interpreted with the symptoms, physical examination, imaging findings, and other laboratory results.
Short name
###2: CSF B2 Transferrin
Frequently asked questions
###14: What does a positive B2 transferrin result mean?
###16: Can a negative result rule out a cerebrospinal fluid leak?
###18: Is this the same as a routine transferrin test?
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