Test Code C5DCU C5-DC Acylcarnitine, Quantitative, Urine
Reporting Name
C5-DC Acylcarnitine, QN, UUseful For
Evaluation of patients with an abnormal newborn screen showing elevations of C5-DC
Diagnosis of glutaric aciduria type 1 deficiency
Performing Laboratory

Specimen Type
UrineNecessary Information
Include patient's age, family history, clinical condition (asymptomatic or acute episode), diet, and drug therapy information.
Specimen Required
Patient Preparation: If clinically feasible, discontinue L-carnitine supplementation at least 72 hours before specimen collection.
Supplies: Urine Tubes, 10 mL (T068)
Collection Container/Tube: Clean, plastic urine collection container
Submission Container/Tube: Plastic, 10-mL urine tube
Specimen Volume: 5 mL
Collection Instructions:
1. Collect a random urine specimen.
2. Freeze specimen immediately.
Specimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Frozen (preferred) | 7 days | |
Refrigerated | 24 hours |
Reference Values
Day(s) and Time(s) Performed
Monday, Wednesday, Friday; 8 a.m.
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
82017
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
C5DCU | C5-DC Acylcarnitine, QN, U | 54279-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
88831 | C5-DC Acylcarnitine, QN, U | 54279-5 |
28126 | C5-DC Interpretation | 59462-2 |
34470 | Reviewed By | 18771-6 |
Clinical Information
An isolated elevation of glutarylcarnitine (C5-DC) in plasma or newborn screening blood spots is related to a diagnosis of glutaric aciduria type 1 (GA-1), also known as glutaric acidemia type 1. GA-1 is caused by a deficiency of glutaryl-CoA dehydrogenase. Urinary excretion of C5-DC is a specific biochemical marker of GA-1 that appears to be elevated even in low excretors, those patients who are affected but have normal levels of glutaric acid in urine.
GA-1 is characterized by bilateral striatal brain injury leading to dystonia, often a result of acute neurologic crises triggered by illness. Many affected individuals also have macrocephaly. Dietary treatment and aggressive interventions during time of illness are recommended to try to prevent or minimize neurologic injury, which is most likely to occur in infancy and early childhood. Prevalence is approximately 1 in 100,000 individuals.
The American College of Medical Genetics (ACMG) newborn screening work group published diagnostic algorithms for the follow-up of infants who had a positive newborn screening result. For more information, see the Practice Resources: ACT Sheets and Algorithms at http://www.acmg.net.
Analytic Time
2 days (not reported on Sunday)Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. |
NY State Approved
YesMethod Name
Flow Injection Analysis-Tandem Mass Spectrometry (FIA-MS/MS)
Forms
If not ordering electronically, complete, print, and send an Inborn Errors of Metabolism Test Request (T798) with the specimen.