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Recommendations when to order or not order the test. May include related or preferred tests.
Useful in the diagnosis of primary carnitine deficiency (carnitine uptake defect). Monitor carnitine status.
New York DOH Approval Status
Indicates whether a test has been approved by the New York State Department of Health.
This test is New York state approved.
Specimen Required
Patient PreparationInstructions patient must follow before/during specimen collection.
CollectSpecimen type to collect. May include collection media, tubes, kits, etc.
Green (sodium or lithium heparin). Also acceptable: Plain red.
Specimen PreparationInstructions for specimen prep before/after collection and prior to transport.
Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 0.5 mL serum or plasma to an ARUP standard transport tube and freeze immediately. (Min: 0.2 mL) Avoid hemolysis.
Storage/Transport TemperaturePreferred temperatures for storage prior to and during shipping to ARUP. See Stability for additional info.
CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.
Unacceptable ConditionsCommon conditions under which a specimen will be rejected.
Room temperature specimens. Specimens refrigerated greater than 12 hours.
RemarksAdditional specimen collection, transport, or test submission information.
StabilityAcceptable times/temperatures for specimens. Times include storage and transport time to ARUP.
After separation from cells: Ambient: Unacceptable; Refrigerated: 12 hours; Frozen: 1 month (avoid repeated freeze/thaw cycles)
Methodology
Process(es) used to perform the test.
Tandem Mass Spectrometry
Performed
Days of the week the test is performed.
Tue-Sat
Reported
Expected turnaround time for a result, beginning when ARUP has received the specimen.
1-4 days
Reference Interval
Normal range/expected value(s) for a specific disease state. May also include abnormal ranges.
Age
Carnitine, Free, Serum/Plasma
Carnitine, Total, Serum/Plasma
Carnitine, Esterified, Serum/Plasma
Carnitine E/F Ratio, Serum/Plasma
1 - 31 days
15 - 55 µmol/L
21 - 83 µmol/L
4 - 29 µmol/L
0.2 - 0.8
32 days-12 months
29 - 61 µmol/L
38 - 73 µmol/L
7 - 24 µmol/L
0.1 - 0.8
13 months - 6 years
25 - 55 µmol/L
35 - 90 µmol/L
4 - 36 µmol/L
0.1 - 0.8
7 years -20 years
22 - 63 µmol/L
31 - 78 µmol/L
3 - 38 µmol/L
0.1 - 0.9
21 years or older
25 - 60 µmol/L
34 - 86 µmol/L
5 - 29 µmol/L
0.1 - 1.0
Interpretive Data
May include disease information, patient result explanation, recommendations, or details of testing.
Compliance Category
Laboratory Developed Test (LDT)
Note
Additional information related to the test.
The concentration of esterified carnitine is derived from a mathematical calculation using free and total carnitine.
Hotline History
N/A
CPT Codes
The American Medical Association Current Procedural Terminology (CPT) codes published in ARUP's Laboratory Test Directory are provided for informational purposes only. The codes reflect our interpretation of CPT coding requirements based upon AMA guidelines published annually. CPT codes are provided only as guidance to assist clients with billing. ARUP strongly recommends that clients confirm CPT codes with their Medicare administrative contractor, as requirements may differ. CPT coding is the sole responsibility of the billing party. ARUP Laboratories assumes no responsibility for billing errors due to reliance on the CPT codes published.
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
Other names that describe the test. Synonyms.
Esterified carnitine
L-Carnitine Free and Total
Free and Total Carnitine
Carnitine, Free & Total (Includes Carnitine, Esterified)
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