Test Code HGEMP Hydroxyglutaric Acids, Glutaric Acid, Ethylmalonic Acid, and Methylsuccinic Acid, Plasma
Useful For
Evaluation of patients with an abnormal newborn screen showing elevations of glutarylcarnitine (C5-DC) using plasma specimens
Evaluation of patients with abnormal newborn screens showing elevations of C4- acylcarnitine to aid in the differential diagnosis of short chain acyl-CoA dehydrogenase and isobutyryl-CoA dehydrogenase deficiencies
Diagnosis of glutaric acidemia type 1
Aiding in diagnosis of glutaric acidemia type 2
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
HGEM, PSpecimen Type
PlasmaNecessary Information
Patient's age is required.
Specimen Required
Collection Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA), green top (lithium heparin)
Submission Container/Tube: Plastic vial
Specimen Volume: 0.1 mL
Collection Instructions: Centrifuge and aliquot plasma into a plastic vial.
Specimen Minimum Volume
0.02 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma | Refrigerated (preferred) | 90 days | |
Frozen | 90 days | ||
Ambient | 12 days |
Reference Values
2-OH Glutaric acid ≤4.5 nmol/mL
3-OH Glutaric acid ≤0.7 nmol/mL
Glutaric acid ≤0.8 nmol/mL
Methylsuccinic acid ≤0.3 nmol/mL
Ethylmalonic acid ≤1.5 nmol/mL
Interpretation
Elevations of ethylmalonic acid (EMA) and methylsuccinic acid (MSA) are consistent with a diagnosis of short chain acyl Co-A dehydrogenase (SCAD) deficiency.
Elevation of EMA is consistent with a diagnosis of ethylmalonic encephalopathy.
Normal levels of EMA in the context of elevated C4 is consistent with a diagnosis of isobutyryl-CoA dehydrogenase (IBDH) deficiency.
Elevation of glutaric acid (GA) and 3-hydroxyglutaric acid (3OH-GA) are consistent with a diagnosis of glutaric acidemia type I (GA1).
Elevation of GA, 2-hydroxyglutaric acid (2OH-GA), 3OH-GA, EMA, and MSA are consistent with a diagnosis of glutaric acidemia type II (GA2).
Clinical Reference
1. Rinaldo P, Cowan TM, Matern D. Acylcarnitine profile analysis. Genet Med. 2008;10(2):151-156
2. Vockley J, Zschocke J, Knerr I, Vockley C, Michael Gibson KK. Branched chain organic acidurias. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA. eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed March 30, 2023. Available at https://ommbid.mhmedical.com/content.aspx?bookid=2709§ionid=225085758
3. Frerman FE, Goodman SI. Defects of electron transfer flavoprotein and electron transfer flavoprotein-ubiquinone oxidoreductase: Glutaric acidemia type II. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed March 30, 2023. Available at https://ommbid.mhmedical.com/content.aspx?bookid=2709§ionid=225088261
4. Larson A, Goodman S. Glutaric acidemia type 1. In: Adam MP, Mirzaa GM, Pagon RA, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2019. Accessed March 30, 2023. Available at www.ncbi.nlm.nih.gov/books/NBK546575/
5. Di Meo I, Lamperti C, Tiranti V. Ethylmalonic encephalopathy. In: Adam MP, Mirzaa GM, Pagon RA, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2017. Accessed March 30, 2023. Available at www.ncbi.nlm.nih.gov/books/NBK453432/
6. Wolfe L, Jethva R, Oglesbee D, Vockley J. Short-chain acyl-CoA dehydrogenase deficiency. In: Adam MP, Mirzaa GM, Pagon RA, et al. eds. GeneReviews [Internet]. University of Washington, Seattle; 2011. Updated August 9, 2018. Accessed March 30, 2023. Available at www.ncbi.nlm.nih.gov/books/NBK63582/
Day(s) Performed
Monday, Wednesday
Report Available
3 to 7 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
83918
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
HGEMP | HGEM, P | 92673-3 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
36062 | 2-OH Glutaric acid | 69845-6 |
36063 | 3-OH Glutaric acid | 69851-4 |
36064 | Glutaric acid | 27301-1 |
36065 | Methylsuccinic acid | 69829-0 |
36066 | Ethylmalonic acid | 79476-8 |
36067 | Interpretation (HGEMP) | 59462-2 |
36068 | Reviewed By | 18771-6 |
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.