Fatty Acid Profile, Peroxisomal (C22-C26), Serum
Use
This test is useful for evaluating patients with possible peroxisomal disorders, such as X-linked adrenoleukodystrophy or peroxisomal biogenesis disorders (e.g., Zellweger syndrome spectrum) using serum specimens. It aids in assessing peroxisomal function by analyzing very long-chain fatty acids and pristanic and phytanic acids, helping diagnose peroxisomal biogenesis disorders and other specific enzyme deficiencies. It is especially appropriate for follow-up of an abnormal newborn screen for X-ALD.
Special Instructions
Not provided.
Limitations
False-positive results may occur with nonfasting specimens. In rare cases, patients with X-linked adrenoleukodystrophy may have only minimally elevated values. It is also noted that 15% to 20% of women heterozygous for X-ALD have normal plasma very long-chain fatty acid levels. These factors can contribute to diagnostic confusion.
Methodology
Mass Spectrometry (GC-MS)
Biomarkers
LOINC Codes
- 43677-4 - VLCFA C22-C26 Pnl SerPl
- 30194-5 - VLCFA C22:0 SerPl-sCnc
- 30195-2 - VLCFA C24:0 SerPl-sCnc
- 30197-8 - VLCFA C26:0 SerPl-sCnc
- 30196-0 - VLCFA C24:0/C22:0 SerPl-sRto
- 30198-6 - VLCFA C26:0/C22:0 SerPl-sRto
- 22761-1 - Pristanate SerPl-sCnc
- 22671-2 - Phytanate SerPl-sCnc
- 30550-8 - Pristanate/Phytanate SerPl-sRto
- 48767-8 - Annotation comment Imp
Result Turnaround Time
3-5 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1.5 mL
Minimum Volume
0.15 mL
Container
Plastic vial
Collection Instructions
Centrifuge and aliquot serum into plastic vial.
Patient Preparation
Fasting: 12 hours, required. Infants and small children should have specimen collected just before next feeding/meal. Patient must not consume any alcohol for 24 hours before the specimen is collected.
Causes for Rejection
Gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 15 days |
| Frozen | 92 days |
