Fatty Acid Profile, Comprehensive (FAPCP)

Test Code: FAPCMSO

Overview
Ordering
Specimen
Performing
Clinical/Interpretive
Contacts
Coding

Synonyms/Keywords

C8-C26, Fatty Acid Profile, Comprehensive Fatty Acids, Essential Fatty Acids, LCFA (Long-Chain Fatty Acids), Long-Chain Fatty Acids (LCFA), MCFA (Medium-Chain Fatty Acids), Medium-Chain Fatty Acids (MCFA), Omega 3, Omega 6, Omega 7, Omega 9, Polyunsaturated Fatty Acids, Very Long Chain Fatty Acids (VLCFA), VLCFA (Very Long Chain Fatty Acids)

Useful For

This test is a comprehensive profile that provides information regarding mitochondrial and peroxisomal fatty acid metabolism, and the patient's nutritional status, and is useful for:

-Monitoring patients undergoing diet therapy for mitochondrial or peroxisomal disorders (possibly inducing essential fatty acid deficiency in response to restricted fat intake)

-Monitoring treatment of essential fatty acid deficiency

-Monitoring the response to provocative tests (fasting tests, loading tests)

-Complete evaluation of patients enrolled in clinical studies

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	Red Top Tube (RTT)	Serum Separator Tube (SST)	0.5 mL	0.15 mL

Collection Processing Instructions

Submit sample in plastic vial.

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

2. Patient must not consume any alcohol for 24 hours before the specimen is drawn.

3. Spin down within 45 minutes of draw.

Additional Information:

1. Patient's age is required.

2. Include information regarding treatment, family history, and tentative diagnosis.

Specimen Stability Information

Specimen Type	Temperature	Time
Serum	Frozen (preferred)	90 days
	Refrigerated	24 hours

Rejection Criteria

Gross lipemia

Performing Laboratory Information

Performing Location	Day(s) Test Performed	Analytical Time	Methodology/Instrumentation
Mayo Medical Laboratories	Monday through Friday	4 days	Gas Chromatography-Mass Spectrometry (GC-MS) Stable Isotope Dilution Analysis

Reference Lab

Mayo Clinic Laboratories

Test Information

This assay is a comprehensive profile that provides information regarding mitochondrial and peroxisomal fatty acid oxidation, as well as the patient's nutritional status. Useful for monitoring patients undergoing diet therapy for mitochondrial or peroxisomal disorders (possibly inducing essential fatty acid deficiency in response to restricted fat intake).

Reference Range Information

See interpretive report

Interpretation

An increased triene/tetraene ratio is consistent with essential fatty acid deficiency.

Fatty acid oxidation disorders are recognized on the basis of disease-specific patterns that are correlated to the results of other investigations in plasma (carnitine, acylcarnitines) and urine (organic acids, acylglycines).

Increased concentrations of serum very long-chain fatty acids (VLCFA) C24:0 and C26:0 are seen in peroxisomal disorders, X-linked adrenoleukodystrophy, adrenomyeloneuropathy, and Zellweger syndrome (cerebrohepatorenal syndrome).

Increased concentrations of serum phytanic acid (along with normal pristanic acid concentrations) are seen in the Refsum disease (phytanase deficiency). Serum phytanic acid concentration also may be increased in other peroxisomal disorders and, when combined with the VLCFA, pristanoic acid and pipecolic acid allow differential diagnosis of peroxisomal disorders.

Outreach CPTs

CPT	Modifier (if needed)	Quantity	Description	Comments
82542