Free Fatty Acids, Total (NEFA)

Test Code: FRFATSO

Overview
Ordering
Specimen
Performing
Clinical/Interpretive
Contacts
Coding

Synonyms/Keywords

Fatty Acids, Free; FATTY ACIDS, FREE (FFA); Free Fatty Acids, Serum; NEFA (Nonesterified Fatty Acids); Non Esterified Fatty Acids

Useful For

Evaluation of metabolic status of persons with endocrinopathies

Monitoring of control of diabetes mellitus.

Monitoring the effects of therapeutic diet/exercise lifestyle changes

Specimen Requirements

Fasting Required	Specimen Type	Preferred Container/Tube	Acceptable Container/Tube	Specimen Volume	Specimen Minimum Volume (allows for 1 repeat)	Pediatric Minimum Volume (no repeat)
Yes	Serum	Serum Separator Tube(SST)	Red Top Tube (RTT)	1 mL	0.5 mL

Collection Processing Instructions

Submit sample in a plastic vial.

1. Fasting-overnight (12-14 hours).

2. Patient must not consume any alcohol for 24 hours before the specimen is collected.
3. Patient should not be receiving therapeutic heparin.

4. Centrifuge within 45 minutes of collection and aliquot 1 mL of serum into a plastic vial.

5. Immediately freeze specimen.

Specimen Stability Information

Specimen Type	Temperature	Time
Serum	Frozen	7 days

Rejection Criteria

Gross hemolysis
Gross lipemia
Gross icterus

Interference

Patients receiving therapeutic heparin are unsuitable for this analysis. Heparin causes the release of free fatty acids by stimulating the activity of lipoprotein lipase, which causes triglycerides associated with blood lipoproteins to release free fatty acids.

In order to eliminate the generation of free fatty acids from triglycerides by serum lipases (causing erroneous elevations), serum should be frozen as soon as possible after it is collected and shipped frozen.

Performing Laboratory Information

Performing Location	Day(s) Test Performed	Analytical Time	Methodology/Instrumentation
Mayo Clinic Laboratories	Monday through Friday	1-3 days	Enzymatic Colorimetric

Reference Lab

Mayo Clinic Laboratories

Test Information

Elevated serum concentrations of nonesterified fatty acids (NEFA) are associated with cardiovascular disease, metabolic syndrome, obesity, and type 2 diabetes mellitus. NEFA are causally linked with insulin resistance and inflammation of vascular endothelium.

Reference Range Information

> or =18 years: 0.00-0.72 mmol/L

Reference values have not been established for patients who are <18 years of age.

Interpretation

Abnormally high levels of free fatty acids are associated with uncontrolled diabetes mellitus and with conditions that involve excessive release of a lipoactive hormone such as epinephrine, norepinephrine, glucagon, thyrotropin, and adrenocorticotropin.

Outreach CPTs

CPT	Modifier (if needed)	Quantity	Description	Comments
82725

Synonyms/Keywords

Fatty Acids, Free; FATTY ACIDS, FREE (FFA); Free Fatty Acids, Serum; NEFA (Nonesterified Fatty Acids); Non Esterified Fatty Acids

Ordering Applications

Ordering Application	Description
Centricity	Free Fatty Acids, Total (8280)
Cerner	Fatty Acids, Free, Total (8280)
COM	Free Fatty Acids, Total (NEFA)

If the ordering application you are looking for is not listed, contact your local laboratory for assistance.