Test Overview
Test Methodology

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

Test Usage

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

Reference Range *

Free Carnitine: 77 - 214 nmol/g creatinine; Total Carnitine: 180 - 412 nmol/g creatinine; Ratio (Acyl to Free): 0.7 - 3.4. Interpretive report provided.

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

Test Limitations

Increased values are obtained after carnitine implementation or meat consumption. It is recommended that plasma concentrations be determined concurrently with urine collection.

Test Details
Days Set Up
Tuesday
Analytic Time

7 - 12 days

Soft Order Code
CARNU
MiChart Code
Carnitine, Urine (Mayo)
Synonyms
  • Carnitine, U
  • CARN RATIO
  • CRNU INTRP
  • FREE_CARN
  • TOTAL_CARN
  • RATIO: ACYL TO FREE
  • Interpretation
  • FREE CARNITINE
  • TOTAL CARNITINE
Laboratory
Sendout
Reference Laboratory
Mayo CARNU (81123)
Section
Special Testing
Specimen Requirements
Collection Instructions

Collect random urine and freeze.

Normal Volume
1.5 ml random urine
Minimum Volume
1.5 ml random urine
Additional Information

Includes total, free, and ratio. Test sent to Mayo Medical Laboratories

Billing
CPT Code
82379
Fee Code
AA237
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