Understanding This Laboratory Test: Purpose, Sample Collection, and What Your Results Mean
This test detects the presence of beta-1 transferrin, a specific protein found in cerebrospinal fluid (CSF), in other body fluids to help diagnose CSF leaks.
{"Beta-1 transferrin is a special protein found mainly in spinal fluid","Its presence in nasal or ear fluid can indicate a cerebrospinal fluid leak","The test uses a simple blood or fluid sample","It helps doctors locate and confirm the source of fluid leakage from the brain or spine"}
Key facts at a glance
- LOINC
- 57837-7
- Short code
- B1TF
- Synonyms
- Beta-1 transferrin Fld Ql
- Category
- chemistry
- Sample
- serum
- Container
- Sterile, leak-proof, plastic screw-cap container without preservative; collect at least 0.5 mL of fluid
- Units
- N/A
- Ref low
- 200
- Ref high
- 350
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Immunofixation electrophoresis or Western blot; may also use nephelometry/turbidimetry for screening
- CPT
- 86335
- SNOMED
- 44608005
- Specimen volume
- 0.5-1.0 mL of body fluid (minimum 0.3 mL)
- Stability
- Refrigerated (2-8°C): up to 7 days; Frozen (-20°C or below): up to 30 days; Room temperature: up to 24 hours
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
What is this test, and what exactly does it measure or detect in your body?
The Beta-1 Transferrin test detects the presence of a specific protein called beta-1 transferrin (also known as tau transferrin) in body fluids. Beta-1 transferrin is a unique form of transferrin that is primarily produced in the brain and is found almost exclusively in cerebrospinal fluid (CSF), the clear fluid that surrounds the brain and spinal cord.
Why is this test performed, and in what situations does your doctor typically order it?
This test is primarily used to diagnose cerebrospinal fluid (CSF) leaks. When the membranes or bones surrounding the brain and spinal cord are damaged, CSF can leak into the nose (CSF rhinorrhea), ears (CSF otorrhea), or other areas. Detecting beta-1 transferrin in these fluids confirms that the leaking fluid is indeed CSF rather than mucus, blood, or other fluids.
How is the sample for this test collected, and what should you expect during the procedure?
For this test, your doctor will collect a small sample of the fluid leaking from your nose, ear, or wound using a sterile swab or container. In some cases, a blood sample may also be taken for comparison. The sample is then sent to a laboratory where it is analyzed using special techniques to detect the presence of beta-1 transferrin.
What do the results of this test mean, and how are normal and abnormal values interpreted?
A positive result means that beta-1 transferrin was detected in the tested fluid, confirming a cerebrospinal fluid leak. A negative result suggests that the fluid is not CSF. Your doctor will interpret these results along with your symptoms, imaging studies, and physical examination to determine the cause and appropriate treatment.
Reference range
NCBI: Transferrin 200-350 mg/dLN/A
No special patient preparation required. Specimen should be collected from suspected leak site (e.g., nasal or ear discharge) in a sterile container. Avoid contamination with blood, tears, or saliva. Standard aseptic technique should be used.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The Beta-1 Transferrin test is crucial for diagnosing cerebrospinal fluid leaks, which can result from head injuries, skull base tumors, sinus surgery, or spontaneous leaks. Early and accurate diagnosis is important because CSF leaks can lead to serious complications such as meningitis (brain infection), brain herniation, and persistent headaches. This test helps surgeons precisely locate the leak site before performing repair surgery, improving outcomes and reducing the need for invasive exploratory procedures.
Frequently asked questions
Is the test painful?
How long does it take to get results?
Are there any risks associated with this test?
What conditions can cause a CSF leak?
How is a CSF leak treated?
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 17, 2026. · Read our editorial policy