Ordering Recommendation

Initial test to screen for disorders of peroxisomal biogenesis and/or function, including X-linked adrenoleukodystrophy and Zellweger syndrome.

Mnemonic
VLCFA
Methodology

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Performed

Tue

Reported

2-9 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation

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.

Unacceptable Conditions

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

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 https://www.aruplab.com/patienthistory or by contacting ARUP Client Services.

Stability

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.

Compliance Statement B: For laboratory developed tests not using a RUO kit, and for FDA approved, cleared or 510(k) exempt assays with alterations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

Note
Hotline History
N/A
CPT Codes

82726

Components
Component Test Code* Component Chart Name LOINC
2004251 Fatty Acids Profile Interpretation 49263-7
2004252 Pristanic Acid 22761-1
2004253 Phytanic Acid 22671-2
2004256 C22:0 Behenic Acid 30194-5
2004257 C24:0 Tetracosanoic Acid 30195-2
2004259 C26:0 Hexacosanoic Acid 30197-8
2004260 Ratio Pristanic to Phytanic 30550-8
2004261 Ratio C24:0 to C22:0 30196-0
2004262 Ratio C26:0 to C22:0 30198-6
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • VLCFA and BCFA
Very Long-Chain and Branched-Chain Fatty Acids Profile