Test Overview

Test Methodology

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

Test Usage

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

Reference Range*

Interpretive report provided.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Increased values may be obtained after carnitine supplementation or meat consumption.

Test Details

Days Test Performed

Monday - Friday

Analytic Time

2 - 5 days

Soft Order Code


MiChart Code

Carnitine, Serum



Carnitine, Serum
Carnitine, Free and Total
AC/FC Ratio

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Laboratory Reference

Mayo CARNS (60449)

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Specimen Requirements


Red Top Tube

Normal Volume

0.5 mL serum

Minimum Volume

0.2 mL serum

Additional Information

Test includes Total Carnitine, Free Carnitine, Acylcarnitine, and AC/FC Ratio. Test sent to Mayo Medical Laboratories.

Billing Information

Fee Codes

CPT Code


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