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
Patient's age and sex are required. Biochemical Genetics Patient Information (T602) is recommended but not mandatory to accompany the specimen to aid in test result interpretation. The patient must fast for 12 hours prior to the test, with no alcohol consumption 24 hours before specimen collection.
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.
New York Approved
Methodology
Mass Spectrometry (GC-MS)
Biomarkers
LOINC Codes
- 43677-4
- 30194-5
- 30195-2
- 30197-8
- 30196-0
- 30198-6
- 22761-1
- 22671-2
- 30550-8
- 48767-8
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 |