ARUP's Laboratory Test Directory

Very Long-Chain and Branched-Chain Fatty Acids Profile : 2004250
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Patient History For Biochemical Genetics
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Additional Technical Information


Mnemonic: VLCFA

Methodology: Liquid Chromatography-Tandem Mass Spectrometry
Performed: Tue
Reported: 2-9 days
Specimen Required: Patient Prep: Adults: Fasting specimen preferred.
Infants and children: Draw specimen prior to feeding or 2-3 hours after a meal.

Collect: Green (sodium or lithium heparin) or lavender (EDTA).

Specimen Preparation: Separate plasma from cells. Transfer 0.5 mL plasma to an ARUP Standard Transport Tube and freeze immediately. (Min: 0.2 mL)

Storage/Transport Temperature: CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.

Remarks: Clinical information is needed for appropriate interpretation. Additional required information includes age, gender, diet (e.g.TPN therapy), drug therapy, and family history. Biochemical Genetics Patient History Form is available on the ARUP Web site at http://www.aruplab.com/patienthistory or by contacting ARUP Client Services.

Unacceptable Conditions: Room temperature specimens greater than 24 hours. Refrigerated specimens greater than 48 hours. Specimens exposed to more than one freeze/thaw cycle.

Stability (collection to initiation of testing): After separation from cells: Ambient: 24 hours; Refrigerated: 72 hours; Frozen: 1 month
Reference Interval:
 
Available Separately Component 0-11 months 1 year to 2 years 3 years to 6 years 7 years and older
No Pristanic Acid Less than 0.31 µmol/L Less than 0.55 µmol/L Less than 0.46 µmol/L Less than 0.26 µmol/L
No Phytanic Acid 0.03-2.13 µmol/L 0.23-5.03 µmol/L 0.33-2.53 µmol/L 0.25- 2.07 µmol/L
No Ratio Pristanic Acid to Phytanic Acid Less than 0.91 Less than 0.28 Less than 0.28 Less than 0.28
No C22:0 Behenic Acid 28.94-93.50 µmol/L 28.94-93.50 µmol/L 28.94-93.50 µmol/L 28.94-93.50 µmol/L
No C24:0 Tetracosanoic Acid 24.25-77.75 µmol/L 24.25-77.75 µmol/L 24.25-77.75 µmol/L 24.25-77.75 µmol/L
No C26:0 Hexacosanoic Acid 0.17-0.73 µmol/L 0.17-0.73 µmol/L 0.17-0.73 µmol/L 0.17-0.73 µmol/L
No Ratio C24:0 to C22:0 0.64-1.02 0.64-1.02 0.64-1.02 0.64-1.02
No Ratio C26:0 to C22:0 0.003-0.015 0.003-0.015 0.003-0.015 0.003-0.015

Interpretive Data: Refer to report.
CPT Code(s): 82726
Cross References: Adrenoleukodystophy (Very Long-Chain and Branched-Chain Fatty Acids Profile), ALD (Very Long-Chain and Branched-Chain Fatty Acids Profile), PBD (Very Long-Chain and Branched-Chain Fatty Acids Profile), Peroxisomal Disorders (Very Long-Chain and Branched-Chain Fatty Acids Profile), Peroxisome Biogenesis Disorders (Very Long-Chain and Branched-Chain Fatty Acids Profile), Refsum (Very Long-Chain and Branched-Chain Fatty Acids Profile), X-ALD (Very Long-Chain and Branched-Chain Fatty Acids Profile), Zellweger Syndrome (Very Long-Chain and Branched-Chain Fatty Acids Profile), ZWS (Very Long-Chain and Branched-Chain Fatty Acids Profile)