Test Code CARNU Carnitine, Random, Urine
Reporting Name
Carnitine, UUseful For
Evaluation of patients with a clinical suspicion of a wide range of conditions including organic acidemias and fatty acid oxidation disorders
Monitoring carnitine treatment
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
UrineSpecimen Required
Supplies: Urine Tubes, 10 mL (T068)
Container/Tube: Plastic, 10-mL urine tube
Specimen Volume: 1.5 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Frozen (preferred) | 365 days | |
Refrigerated | 72 hours |
Reference Values
FREE CARNITINE:
77-214 nmol/mg of creatinine
TOTAL CARNITINE:
180-412 nmol/mg of creatinine
RATIO:
Acylcarnitine to free carnitine: 0.7-3.4
Day(s) Performed
Tuesday
Test 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
82379
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CARNU | Carnitine, U | 100428-2 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
27121 | Total | 17866-5 |
27122 | Free (FC) | 17867-3 |
15789 | AC/FC Ratio | 43576-8 |
21550 | Interpretation | 59462-2 |
Interpretation
When abnormal results are detected, a detailed interpretation is given, including an overview of the results and of their significance, a correlation to available clinical information, elements of differential diagnosis, recommendations for additional biochemical testing and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.
Clinical Reference
1. Magoulas PL, El-Hattab AW. Systemic primary carnitine deficiency: an overview of clinical manifestations, diagnosis, and management. Orphanet J Rare Dis. 2012; 18;7:68
2. Longo N, Amat di San Filippo C, Pasquali M. Disorders of carnitine transport and the carnitine cycle. Am J Med Genet C Semin Med Genet. 2006 15;142C(2):77-85
3. Zammit VA, Ramsay RR, Bonomini M, Arduini A. Carnitine, mitochondrial function and therapy. Adv Drug Deliv Rev. 2009;61(14):1353-1362
4. El-Hattab AW: Systemic primary carnitine deficiency. In: Adam MP, Ardinger HH, Pagon RA, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2012. Updated November 3, 2016. Accessed November 27, 2023. Available at www.ncbi.nlm.nih.gov/books/NBK84551/
5. Almannai M, Alfadhel M, El-Hattab AW. Carnitine inborn errors of metabolism. Molecules. 2019;24(18):3251
6. Longo N., Frigeni M., Pasquali M. Carnitine transport and fatty acid oxidation. Biochim. Biophys. Acta. 2016;1863(10):2422-2435
Report Available
3 to 9 daysMethod Name
Flow Injection Analysis-Tandem Mass Spectrometry (FIA-MS/MS)
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.