Acylcarnitinepatternurimp
A urine test that analyzes acylcarnitine levels to help diagnose metabolic disorders affecting how your body converts food into energy.
{"This test measures specific compounds (acylcarnitines) in your urine that indicate how your body breaks down fats for energy","It helps doctors detect inherited metabolic disorders, especially in newborns and children with unexplained symptoms","Abnormal results may suggest problems with fatty acid oxidation, which can cause low blood sugar, muscle weakness, or organ damage","The test uses a urine sample collected at home or in the clinic","Follow-up testing is often needed to confirm a diagnosis"}
Key facts at a glance
- LOINC
- 33472-2
- Short code
- ACY-U
- Synonyms
- Acylcarnitine pattern Ur-Imp
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container (no preservatives)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Tandem mass spectrometry (MS/MS) with interpretation of acylcarnitine profile
- CPT
- 82017
- SNOMED
- 122442009
- Specimen volume
- 5-10 mL (minimum 2 mL)
- Stability
- Refrigerate 2-8°C for up to 7 days; freeze at -20°C or below for long-term storage. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 72–168 hours
- Order
- routine
What is this test?
The urine acylcarnitine pattern test measures the levels of different acylcarnitines in your urine. Acylcarnitines are substances produced when your body breaks down fatty acids (fats) to use as energy. This test helps doctors see if your body is properly processing fats for energy, which is essential for normal body function.
Why might I need this test?
Your doctor may order this test if you or your child has symptoms suggesting a metabolic disorder, such as: unexplained low blood sugar, muscle weakness or pain, heart problems, developmental delays, or episodes of illness that worsen during fasting. It is also commonly used as part of newborn screening programs to detect inherited metabolic disorders early.
How is the test done?
You will need to provide a urine sample. Your healthcare provider will give you a sterile container for collecting the sample at home or at the clinic. For accurate results, you may be asked to collect the first morning urine or a sample after a specific fasting period. The sample is then sent to a laboratory where specialists use special equipment to measure the levels of different acylcarnitines.
What do the results mean?
Results show the pattern and levels of different acylcarnitines in your urine. Abnormal patterns may indicate specific metabolic disorders. Your doctor will interpret the results based on your symptoms, medical history, and other test results. Sometimes, abnormal results may be due to other health conditions or medications, so follow-up testing is often necessary to confirm a diagnosis.
Reference range
Normal acylcarnitine pattern in urine. No abnormal elevations detected. Refer to specific analyte concentrations for detailed interpretation.N/A
No fasting required. Collect random urine sample. Inform laboratory of any medications, especially antibiotics or metabolic agents. Provide relevant clinical history including any acute illness episodes.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings2
Frequently asked questions
Is this test painful?
Do I need to fast before the test?
How long does it take to get results?
What happens if my results are abnormal?
Can adults have this test?
Sources
- 1
- 2
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy