Hydroxyglutaric Acids, Glutaric Acid, Ethylmalonic Acid, and Methylsuccinic Acid, Plasma
Use
This test is useful for evaluating patients with abnormal newborn screens showing elevations of glutarylcarnitine (C5-DC) and C4 acylcarnitine. It aids in the differential diagnosis of short chain acyl-CoA dehydrogenase deficiency and isobutyryl-CoA dehydrogenase deficiencies. It also assists in diagnosing glutaric acidemia types 1 and 2 by providing insights based on plasma levels of specific acids like ethylmalonic and methylsuccinic acids. The test enriches understanding of metabolic disorders linked to fatty acid oxidation and organic acids.
Special Instructions
Patient's age is required for test processing. If not ordering electronically, complete and submit the Biochemical Genetics Test Request form with the specimen.
Limitations
The test is limited by its inability to differentiate between certain isomers using acylcarnitine analysis alone. However, additional testing of specific acids using LC-MS/MS improves the differentiation capability among C4 acylcarnitine and glutarylcarnitine/C10-OH isomers. The test is also not FDA approved, which may factor into its use in specific patient populations or diagnoses.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 92673-3
- 69851-4
- 69845-6
- 27301-1
- 69829-0
- 79476-8
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
0.1 mL
Minimum Volume
0.02 mL
Container
Plastic vial
Collection Instructions
Centrifuge and aliquot plasma into a plastic vial.
Causes for Rejection
None listed for gross hemolysis, lipemia, or icterus.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 12 days |
| Refrigerated | 90 days |
| Frozen | 90 days |