Test Code CARNS Carnitine, Serum
Reporting Name
Carnitine, SUseful For
Evaluation of patients with a clinical suspicion of a wide range of conditions including organic acidemias, fatty acid oxidation disorders, and primary carnitine deficiency using serum specimens
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumNecessary Information
Patient's age is required.
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
0.2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Frozen (preferred) | 60 days | |
Refrigerated | 21 days | ||
Ambient | 7 days |
Reference Values
|
Total carnitine (TC) |
Free carnitine (FC) |
Acylcarnitine (AC) |
AC/FC Ratio |
Age Group |
Range* |
Range* |
Range* |
Range |
≤1 day |
23-68 |
12-36 |
7-37 |
0.4-1.7 |
2-7 days |
17-41 |
10-21 |
3-24 |
0.2-1.4 |
8-31 days |
19-59 |
12-46 |
4-15 |
0.1-0.7 |
32 days-12 months |
38-68 |
27-49 |
7-19 |
0.2-0.5 |
13 months-6 years |
35-84 |
24-63 |
4-28 |
0.1-0.8 |
7-10 years |
28-83 |
22-66 |
3-32 |
0.1-0.9 |
11-17 years |
34-77 |
22-65 |
4-29 |
0.1-0.9 |
≥18 years |
34-78 |
25-54 |
5-30 |
0.1-0.8 |
Schmidt-Sommerfeld E, Werner E, Penn D: Carnitine plasma concentrations in 353 metabolically healthy children. Eur J Pediatr. 1988;147:356-360
Used with permission of European Journal of Pediatrics.
Day(s) Performed
Monday through Friday
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 |
---|---|---|
CARNS | Carnitine, S | 97182-0 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
32045 | Total | 14288-5 |
32046 | Free (FC) | 14286-9 |
32047 | Acylcarnitine (AC) | 14282-8 |
32048 | AC/FC Ratio | 30193-7 |
32049 | 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;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. Longo N., Frigeni M., Pasquali M. Carnitine transport and fatty acid oxidation. Biochim. Biophys. Acta. 2016;1863:2422-2435
6. Almannai M, Alfadhel M, El-Hattab AW. Carnitine inborn errors of metabolism. Molecules. 2019;24(18):3251
Report Available
3 to 5 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.