Carnitine Profile, Quantitative, Urine

Condition Description

Carnitine deficiency can be from a primary defect or can be a secondaryeffect. Primary carnitine deficiency can be the result of severalmetabolic conditions including Carnitine Uptake Deficiency (CUD),Carnitine Acylcarnitine Transporter (CACT) Deficiency, CarnitinePalmitoyltransferase I (CPT I) Deficiency, CarnitinePalymitoltransferase II (CPTII) Deficiency. Primary carnitinedeficiency can present with:
  • hypoketotic hypoglycemia encephalopathy
  • hepatomegaly
  • cardiomyopathy
  • muscle weakness
  • gastrointestinal dysmotility
  • hypochromic anemia
Secondary carnitine deficiency results from another metabolicdisorder, such as another fatty acid oxidation disorder, or an organicacidemias leading to carnitine depletion secondary to the formation ofacylcarnitines for excretion of accumulating by products. Secondarycarnitine deficiency can present with symptoms of:
  • encephalopathy
  • hypotonia
  • hepatomegaly
  • cardiac hypertrophy
  • failure to thrive
  • hypoglycemia
  • ketoacidosis
  • hyperammonemia

Genes (0)


This test is indicated for patients with:
  • lethargy/hypotonia
  • myopathy (cardiac/skeletal)
  • clinical suspicion of a fatty acid oxidation defect and an organic acidemia
  • renal dysfunction
  • positive newborn screening result with decreased free carnitine and/or abnormal acylcarnitine profile
The test is most commonly performed in serum or plasma. A urinecarnitine profile is recommended in addition to a plasma carnitineprofile in patients suspected of having a primary disorder of carnitinetransport.


Electrospray Tandem Mass Spectrometry (MS/MS).

Detection and Reference Range

Detection of carnitine deficiency can be sensitive to the age and eating status of the patient.
Reference Range

Total Carnitine (nmol/mg creatinine)
Free Carnitine (FC) (nmol/mg creatinine)
Acylcarnitine (AC) (nmol/mg creatinine)
2 - 8 Years
60 - 295
35 - 93
42 - 232
0 - 4.4
> 8 Years
187 - 313
16 - 158
153 - 226
0 - 4.4

Specimen Requirements

Listed below are EGL's preferred sample criteria. For any questions, please call 470.378.2200 and ask to speak with a laboratory genetic counselor (
Submit only 1 of the following specimen types

Clean container without additives
2-5 ml
Freeze sample. Fasting or first void sample is preferable.
Collection and Shipping
Ship frozen sample on dry ice with overnight delivery.

Special Instructions

Please indicate any medications or dietary changes on the test requisition form.
  • Organic Acids Profile (OA)
  • Acylcarnitine Profile (AR) - Plasma

How to Order