Acylcarnitine Profile, Plasma/Serum (Sendout)

Clinical Utility: Analysis of acylcarnitines is useful in diagnosis of defects in fatty acid beta-oxidation and various disorders of organic acid metabolism. Acylcarnitine analysis is often used in conjunction with urine organic acid analysis in the diagnosis of these disorders and in followup of presumptive positive newborn screening results.

Test Description: Measurement of acylcarnitines by ESI-MS/MS using stable isotope internal standards. Free carnitine is also reported. To order Free/Total Carnitine only, see separate test Carnitine Group (Sendout) [RCARNG].

Ordering Requirements: Include relevant clinical information (drug therapy, family history, etc.) in the Epic order comment to ensure proper interpretation.

Ordering Guidance: This test should be ordered for plasma or serum samples only. Plasma is the preferred sample type, especially for follow-up testing of an abnormal newborn screen. Dried blood spot testing should only be performed on neonates when blood volume is a concern. To order, refer to separate test, Acylcarnitine Profile, Blood Spots (Sendout).

3 mL blood in DARK GREEN (Na Heparin) or LIME PST (Li Heparin)

• Note: Plasma is the preferred specimen type for this test, especially for follow up testing of an abnormal newborn screen.

Also Accepted: GOLD SST, RED, or LAVENDER (EDTA)

Outside Laboratories: Centrifuge sample and aliquot plasma or serum to a separate plastic vial. Freeze plasma/serum at -20°C while awaiting shipment. Transport samples on dry ice.

• Optional: To ensure proper interpretation, include relevant clinical information (drug therapy, and family history) on the DLMP requisition.

Stability (Plasma/Serum): Frozen (preferred): 1 month; Refrigerated: 5 days; Ambient: 5 days.

Centrifuge sample and aliquot plasma or serum to a separate plastic vial. Freeze plasma/serum at -20°C.

Sendouts:

• Order SEACHL Test: LAB429
• Interfaced: Yes [Interface: 601; Department: SOSC]
• If clinical information (drug therapy, family history) is included with the order (optional), print the Epic requisition and send it with a completed SEACHL Biochemical Genetics requisition.
• Send plasma or serum samples on dry ice via DLMP or Delivery Express courier.

Stability (Plasma/Serum): Frozen (preferred): 1 month; Refrigerated: 5 days; Ambient: 5 days.