Test Catalog

Test Id : BETA2

Beta-2 Transferrin: Detection of Spinal Fluid in Other Body Fluid

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detection of spinal fluid in body fluids, such as ear or nasal fluid

Method Name
A short description of the method used to perform the test


NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Beta-2 Transferrin, BF

Lists additional common names for a test, as an aid in searching

B2 Transferrin

Cerebrospinal Fluid Leakage

CSF Specific Transferrin

Otorrhea, Spinal Fluid

Rhinorrhea, Spinal Fluid

Tau Protein

Transferrin B2

Transferrin, Spinal Fluid

Specimen Type
Describes the specimen type validated for testing

Body Fluid

Additional Testing Requirements

If specimens are collected from multiple sites on the body (ie, left and right), each specimen must be sent under a separate order.

Necessary Information

Indicate specimen source. Include whether the source is from the right or left side of the body, if applicable.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Specimen Type: Body fluid

Sources: Nasal, otic, wound, etc


Preferred: Sterile container, syringe, test tube, or microtube

Acceptable: Plain cotton swab or gauze

Specimen Volume: 0.5 mL

Collection Instructions:

1. If submitting a syringe, remove needle. Add cap to end of syringe.

2. If direct collection is not feasible, specimen may be collected using a plain cotton swab or gauze.

3. If gauze is used to collect specimen, circle area on the gauze where specimen was collected.

4. Place cotton swab or gauze in as small a container as possible (eg, plain test tube or collection container).

5. Do not collect specimen with a culture swab.

6. Do not add any liquid to the swab or gauze.

Additional Information:

1. Specimens collected from above the shoulders risk salivary contamination, which can degrade the beta-2 transferrin protein. These specimens should be frozen immediately following collection and kept frozen until testing is performed.

2. Although results may be obtainable on smaller specimens (perhaps as little as 0.05 mL, depending on the protein concentrations and percentage of spinal fluid in the specimen), reliable results are best obtained with an adequate specimen volume.

3. Specimens collected with additives such as microbiology media (eg, Stuart or Amies liquid medium) or TransFix/EDTA (used for analyses in flow cytometry) yield uninterpretable results and will be rejected.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

See Specimen Required

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Body Fluid Frozen (preferred)

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detection of spinal fluid in body fluids, such as ear or nasal fluid

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

The diagnosis of cerebrospinal fluid (CSF) rhinorrhea or otorrhea (leakage of CSF into the nose or ear canal, usually as a result of head trauma, tumor, congenital malformation, or surgery) is often difficult to confirm. Traditional chemical analyses (eg, glucose, protein, specific gravity) are unreliable. Radiographic studies, especially those involving the injection of dyes or radiographic compounds, are costly and may introduce additional risks to the patient.


Transferrin that migrates in the beta-1 electrophoretic fraction (beta-1 transferrin) is found in most body fluids. Beta-2 transferrin is a CSF-specific variant of transferrin and is used as an endogenous marker of CSF leakage. Beta-2 transferrin is formed by loss of sialic acid due to the presence of neuraminidase in the central nervous system. Beta-2 transferrin has also been called CSF-specific transferrin and tau protein.


Prompt diagnosis and localization facilitates appropriate decisions and decreases the risk of meningitis.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

Negative, no beta-2 transferrin (spinal fluid) detected

Provides information to assist in interpretation of the test results

The cerebrospinal fluid (CSF) variant of transferrin is identified by its unique electrophoretic migration. If beta-1 and beta-2 transferrin are detected in drainage fluids, the specimen is presumed to be contaminated with CSF.


The presence of beta-2 transferrin band is detectable with as little as 2.5% spinal fluid contamination of body fluid.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Beta-2 transferrin is also found in aqueous humor and in serum of patients with rare metabolic glycoprotein disorders or genetic variants of transferrin.


Specimens stored in storage tubes with TransFix/EDTA (used for analyses in flow cytometry) are not acceptable. The contact of cerebrospinal fluid with the stabilization solution contained in these tubes changes the migration and the result cannot be interpreted.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Oberascher G: Cerebrospinal fluid otorrhea--new trends in diagnosis. Am J Otol. 1988;9(2):102-108

2. Normansell DE, Stacy EK, Booker CF, et al: Detection of beta-2 transferrin in otorrhea and rhinorrhea in a routine clinical laboratory setting. Clin Diag Lab Immunol. 1994 Jan;1(1):68-70. doi: 10.1128/cdli.1.1.68-70.1994

3. Sanders EL, Clark RJ, Katzmann JA: Cerebrospinal fluid leakage: agarose gel electrophoresis detection of beta(2)-transferrin and nephelometric quantification of beta-trace protein. Clin Chem. 2004 Dec;50(12):2401-2403. doi: 10.1373/clinchem.2004.040246

4. McCudden CR, Senior BA, Hainsworth S, et al: Evaluation of high resolution gel beta (2)-transferrin for detection of cerebrospinal fluid leak. Clin Chem Lab Med. 2013 Feb;51(2):311-315. doi: 10.1515/cclm-2012-0408

5. O'Cearbhaill RM, Kavanagh EC: Beta-2 Transferrin and IR. J Vasc Interv Radiol. 2018 Mar;29(3):439. doi: 10.1016/j.jvir.2017.10.002

6. Zervos TM, Macki M, Cook B, Schultz LR, Rock JP, Craig JR: Beta-2 transferrin is detectable for 14 days whether refrigerated or stored at room temperature. Int Forum Allergy Rhinol. 2018 Sep;8(9):1052-1055. doi: 10.1002/alr.22136

Method Description
Describes how the test is performed and provides a method-specific reference

Specimens are electrophoresed using a high resolution 1% agarose gel, immunofixed with an antiserum to human transferrin that is conjugated with horseradish peroxidase. The immunoprecipitated transferrin bands are visualized with dimethyl sulfoxide. Although most body fluids contain transferrin, the beta 2 variant of transferrin is found exclusively in cerebrospinal fluid (CSF). If the sample is contaminated with CSF, transferrin will be visualized in the beta 1 and beta 2 zones. This reagent set is provided by Sebia.(Package insert: Hydrogel 6 CSF kit, Sebia; 07/2020; Meurman OH, Irjala K, Suonpaa J, Laurent B: A new method for the identification of cerebrospinal fluid leakage. Acta Otolaryngol.Mar-Apr 1979;87(3-4):366-9; Reisinger PW, Hochstrasser K: The diagnosis of CSF fistulae on the basis of detection of beta-2 transferrin by polyacrylamide gel electrophoresis and immunoblotting. J Clin Chem Clin Biochem. 1989;27(3):169-172)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

1 to 3 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
BETA2 Beta-2 Transferrin, BF 13876-8
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
80351 Beta-2 Transferrin, BF 13876-8

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
Test Status - Test Resumed 2023-05-22
Obsolete Test 2023-05-09