Amino Acid Profile, Quantitative, Plasma

Plasma, frozen

0.5 mL

0.15 mL (Note: This volume does not allow for repeat testing.)

Preferred: Frozen plasma from green-top (sodium heparin) tube. Acceptable: Frozen plasma from green-top (lithium heparin) tube, frozen plasma from lavender-top (EDTA) tube or frozen plasma from PPT™. Frozen serum from serum separator tube (SST) or frozen serum from red-top tube will not be rejected. Note: Plasma reference ranges will be applied to all specimen types.

Diagnosis and monitoring of inherited aminoacidurias, organic acidurias, and urea cycle defects. May be used as a follow-up confirmatory test to some abnormal newborn screen results.

False-negative results can occur, especially when a patient is affected with a mild or intermittent variant of a disorder or when clinical condition or dietary treatment causes secondary changes to the profile. Results of amino acid profiling should be interpreted in the context of clinical presentation, as well as other laboratory tests. Frozen serum may be diagnostic, however, certain amino acids may be falsely elevated or low.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Liquid chromatography/tandem mass spectrometry (LC/MS-MS)

See Plasma Amino Acid Reference Intervals in the Test Resources pages online.