Lab Test

Carnitine, Plasma

CARN, This test includes Free and Total

Test Codes



Send Outs

Specimen Collection Criteria

Collect (preferred specimen): One Dark Green-top Sodium Heparin tube.
Also acceptable: One Dark Green-top Lithium Heparin or Lavender-top EDTA tube.

Do not use Plasma Separator Tubes. 

Physician Office/Draw Specimen Preparation

Centrifuge to separate plasma from cells. Transfer plasma to a plastic transport tube and freeze (2-8°C or 36-46°F).

Preparation for Courier Transport

Transport: 0.5 mL plasma, frozen (2-8°C or 36-46°F). (Minimum: 0.2 mL)

Rejection Criteria

Specimens not collected and processed as indicated.

In-Lab Processing

Centrifuge to separate plasma from cells. Transfer plasma to a plastic transport tube and freeze (2-8°C or 36-46°F).

Transport: 0.5 mL plasma, refrigerated (2-8°C or 36-46°F). (Minimum: 0.2 mL)


Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 7 days
Refrigerated (2-8°C or 36-46°F): 21 days
Frozen (-20°C/-4°F or below): 60 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Sendout Laboratory with any questions.


Sent to Mayo Medical Laboratories, Rochester, MN.


Monday – Friday.
Results available in 3-6 days.

Reference Range

By report.

Test Methodology

Flow Injection Analysis-Tandem Mass Spectrometry (FIA-MS/MS).

Clinical Utility

Evaluation of patients with a clinical suspicion of a wide range of inborn errors of metabolism, especially organic acidemias and fatty acid oxidation disorders including primary carnitine deficiency.

Other conditions that are associated with an abnormal carnitine status are neuromuscular diseases, gastrointestinal disorders, familial cardiomyopathy, renal tubulopathies and chronic renal failure (dialysis), and prolonged treatment with steroids, antibiotics (pivalic acid), anticonvulsants (valproic acid), and total parenteral nutrition.

CPT Codes

LOINC:  Total 14288-5, Free 14286-9


Last Updated


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