Test Catalog

Test Id : BFLA1

Lipid Analysis, Body Fluid

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

Distinguishing between chylous and nonchylous effusions

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

Colorimetry/Spectrophotometry (SP)/Electrophoresis


Quantitates cholesterol and triglycerides. Test includes an interpretation.

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

Lipid Analysis, BF

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

Cholesterol, Body Fluids

Cholesterol, Total, Body Fluids

Chylomicron, Body Fluids

Chylothorax Analysis, Abnormal Body Fluid

Chylothorax Lipid Analysis, Abnormal Body Fluid

Fat, Body Fluids

Lipid Analysis, Body Fluid

Lipid Survey, Abnormal Body Fluid

BFLA1 Chyle

Triglyceride, Body Fluids

Specimen Type
Describes the specimen type validated for testing

Body Fluid

Necessary Information

1. Date and time of collection are required.

2. Specimen source is required.


Question ID Description Answers
FLD28 Fluid Type:

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

Specimen Type: Body fluid

Preferred Sources:

Peritoneal fluid (peritoneal, abdominal, ascites, paracentesis)

Pleural fluid (pleural, chest, thoracentesis)

Drain fluid (drainage, JP drain)



Acceptable Source: Write in source name with source location (if appropriate)


Collection Container/Tube: Sterile container, no additive

Submission Container/Tube: Plastic vial

Specimen Volume: 3 mL

Collection Instructions:

1. Centrifuge to remove any cellular material and transfer into a plastic vial.

2. Indicate the specimen source and source location on label.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.

2.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis OK
Gross lipemia OK
Gross icterus OK
Breast milk
Nasal secretions
Gastric secretions
Bronchoalveolar lavage (BAL or bronchial washings)
Amniotic fluid
Feces Saliva
Spinal fluid
Synovial fluid
Vitreous fluid

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) 30 days
Refrigerated 7 days
Ambient 24 hours

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

Distinguishing between chylous and nonchylous effusions

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

Measurement of cholesterol and triglycerides combined with detection of chylomicrons in body fluids is useful for diagnosing chylous effusion or differentiating from pseudochylous effusion.(1) Chylous effusions are characterized by the presence of chyle, which contains chylomicrons circulating through the lymphatic system. Pseudochylous effusions do not have chylomicrons. Cholesterol concentrations in serous effusions increase over time due to chronic exudative processes that cause cell lysis or increased vascular permeability. These fluids have a milky appearance can be confused with chylous effusions. While chylous effusions often have elevated triglyceride concentrations and decreased cholesterol concentrations, identification of chylomicrons is considered the gold standard for the diagnosis.


Pleural Fluid:

Chylothorax is the name given to pleural effusions containing chylomicrons. They develop when chyle accumulates from disruption of the lymphatic system, often the thoracic duct, caused mainly by malignancy or trauma.(1) Lymph fluid contains chylomicron-rich chyle characterized by high concentrations of triglycerides. Pseudochylous effusions are the name given to milky appearing effusions that do not contain lymphatic contents but rather form gradually through the breakdown of cellular lipids in long-standing effusions such as rheumatoid pleuritis, tuberculosis, or myxedema, and, by definition, the effluent contains high concentrations of cholesterol.(2) Differentiation of pseudochylothorax from chylothorax is important as their milky or opalescent appearance is similar, however therapeutic management strategies differ.


Peritoneal Fluid:

Chylous ascites is the name given to peritoneal effusions containing chylomicrons. Obstruction of lymph flow causing leakage from dilated subserosal lymphatics, exudation through the walls of retroperitoneal megalymphatics, and direct leakage of chyle due to a lymphoperitoneal fistula have been proposed as possible mechanisms causing chylous ascites.(3) Elevated triglyceride concentrations have the best correlation with detection of chylomicrons, while cholesterol is not useful at predicting the presence or absence of chylomicrons.

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.

An interpretive report will be provided.

Provides information to assist in interpretation of the test results

Pleural Fluid:

Pleural fluid cholesterol concentrations 46 to 65 mg/dL are consistent with exudative effusions.

Cholesterol concentrations greater than 200 mg/dL suggest pseudochylous effusion.

Triglyceride concentrations greater than 110 mg/dL are consistent with chylous effusions.

Triglyceride concentrations less than 50 mg/dL are usually not due to chylous effusions.


Peritoneal Fluid:

Peritoneal fluid triglyceride concentrations greater than 187 mg/dL are most consistent with chylous effusion.

Cholesterol concentrations 33 to 70 mg/dL suggest malignant causes of ascites.

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

No significant cautionary statements

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

1. Hooper C, Lee YC, Maskell N: BTS Pleural Guideline Group. Investigation of a unilateral pleural effusion in adults: British Thoracic Society Pleural Disease Guideline 2010. Thorax. 2010;65(Suppl2):ii4-17

2. Staats BA, Ellefson RD, Budahn LL, et al: The lipoprotein profile of chylous and nonchylous pleural effusions. Mayo Clin Proc. 1980;55:700-704

3. Thaler MA, Bietenbeck A, Schulz C, et al: Establishment of triglyceride cut-off values to detect chylous ascites and pleural effusions. Clin Biochem. 2017;50(3) 134-138

4. Burtis CA, Ashwood ER, Bruns DE, Tietz NW, eds: In: Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 5th ed. Elsevier; 2012:1 (xviii, 2238)

5. Noble RP: Electrophoretic separation of plasma lipoproteins in agarose gel. J Lipid Res 1968;9:693-700

6. Sepiashvili L, Dahl AR, Meeusen JM, et al: A man with recurrent ascites after laparoscopic cholecystectomy, Clin Chem. 2017;63(7):1199-1203

7. Ellefson RD, Elveback L, Weidman W: Application of methods used for lipoprotein analysis: plasma lipoproteins of children and youths in Rochester, MN. DHEW Publication No. (NIH). 1978;78-1472

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


Samples are analyzed for qualitative interpretation of chylomicrons and plasma lipoproteins using a lipid specific Sudan black stain.(Package insert: Hydragel 7, 15 and 30 LIPO + Lp(a). Sebia Inc; 09/2019)



Cholesterol esters are cleaved by the action of cholesterol esterase to yield free cholesterol and fatty acids. Cholesterol oxidase then catalyzes the oxidation of cholesterol to cholest-4-en-3-one and hydrogen peroxide. In the presence of peroxidase, the hydrogen peroxide formed effects the oxidative coupling of phenol and 4-aminophenazone to form a red quinone-imine dye. The color intensity of the dye formed is directly proportional to the cholesterol concentration. It is determined by measuring the increase in absorbance.(Package insert: Cholesterol Gen2 Reagent. Roche Diagnostics; V 13.0, 02/2019)



Samples analyzed for triglycerides are measured by an automated enzymatic method. The chemistry includes hydrolysis of the triglycerides and phosphorylation of the resulting glycerol.(Package insert: Roche Triglycerides Reagent, Roche Diagnostics;  Corporation, Indianapolis, IN. V7.0, 07/2017)

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.

3 to 4 days

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

3 weeks

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


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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 has been modified from the manufacturer's instructions. Its performance characteristics were 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.

82664-Electrophoretic technique, not elsewhere specified (Chylomicrons and lipoproteins)

84311-Spectrophotometry, analyte not specified (Cholesterol)


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
BFLA1 Lipid Analysis, BF 94872-9
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.
BFCMT Comment 21025-2
FLD28 Fluid Type: 14725-6
BFCHO Cholesterol, BF 12183-0
BFTRG Triglycerides, BF 12228-3

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