Platform
Company
Immunology & Autoimmune
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Currently under review
Pending specialist review and validation.
This test measures hexanoylcarnitine, also called C6, in your blood. Hexanoylcarnitine is a medium‑chain acylcarnitine formed when your body breaks down certain fats for energy inside the mitochondria. It is one part of an acylcarnitine profile performed by tandem mass spectrometry.
Doctors use this measurement to help screen for and evaluate inherited conditions that affect how the body uses fat for energy. It is often included in newborn screening panels and may also be ordered during a metabolic workup at any age.
Abnormal C6 levels can suggest a problem with medium‑chain fat oxidation. When this pathway is not working well, the body may struggle to maintain energy during fasting or illness, which can lead to low blood sugar, lethargy, or liver stress. Finding a pattern of changes across several acylcarnitines, including C6, can point to specific fatty acid oxidation disorders.
Your clinician may order this test if there are concerning symptoms, as follow‑up to a newborn screen, or to monitor a known metabolic condition. Results can guide diet, feeding schedules, and other treatments that reduce the risk of metabolic decompensation.
Your result is interpreted alongside other acylcarnitines, your age, diet, and how you were feeling when the sample was taken. A higher than expected result does not by itself confirm a diagnosis, but it can prompt repeat testing and targeted follow‑up such as a full acylcarnitine profile, urine organic acids, plasma acylglycines, and possibly genetic testing. Low values are usually not concerning and are typically interpreted in context.
If your result is outside the expected range, your care team may ask about recent fasting, illness, diet, and medications, and may suggest avoiding prolonged fasting while evaluation continues. For infants, results are interpreted with special attention to feeding patterns and growth. Always discuss your specific result and next steps with your clinician.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Time since the last feed or meal can influence C6. Prolonged fasting or catabolic states tend to raise medium‑chain acylcarnitines. Tell your clinician when you last ate and whether you were ill at the time of collection.
Fever, vomiting, or other acute illnesses increase energy demand and can change acylcarnitine patterns. Testing during or shortly after illness may show transient elevations, so repeat testing in recovery may be recommended.
Use of medium‑chain triglyceride products, ketogenic diets, or carnitine supplements can alter acylcarnitine levels, including C6. Share details about formulas, nutrition shakes, and over‑the‑counter products with your care team.
Some medicines, such as valproic acid or certain anticonvulsants, can affect fatty acid metabolism and acylcarnitine results. Provide a complete list of prescriptions and recent short‑term treatments to avoid misinterpretation.
Newborns, especially those born early, can have different baseline acylcarnitine patterns than older children and adults. Laboratories use age‑appropriate interpretation to account for these differences.
Results from plasma or serum may differ from dried blood spot screening. Proper collection and prompt processing help ensure accurate measurement and reduce pre‑analytic variation.
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