POX - Overview: Fatty Acid Profile, Peroxisomal (C22-C26), Serum

Test Catalog

Test Name

Test ID: POX    
Fatty Acid Profile, Peroxisomal (C22-C26), Serum

Useful For Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with possible peroxisomal disorders, single-enzyme defects of peroxisomal metabolism such as X-linked adrenoleukodystrophy or peroxisomal biogenesis disorders (Zellweger syndrome spectrum)


An aid in the assessment of peroxisomal function

Genetics Test Information Provides information that may help with selection of the correct test or proper submission of the test request

Reports include concentrations of C22:0, C24:0, C26:0 species, phytanic acid and pristanic acid, and calculated C24:0/C22:0, C26:0/C22:0, and phytanic acid/pristanic acid ratios.


This test analyzes very long-chain fatty acids (VLCFA) as well as pristanic and phytanic acid to aid in diagnosis of peroxisomal biogenesis disorders (PBD), X-linked adrenoleukodystrophy (X-ALD), and Refsum disease.


A fasting sample is required for most accurate results.


This test is also appropriate for follow-up of an abnormal newborn screen for X-ALD.

Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.

See Newborn Screen Follow-up for X-Linked Adrenoleukodystrophy in Special Instructions.


For more information, see Newborn Screening Act Sheet X-linked Adrenoleukodystrophy: Increased Very Long Chain Fatty Acids in Special Instructions.

Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test

Method Name A short description of the method used to perform the test

Gas Chromatography-Mass Spectrometry (GC-MS) Stable Isotope Dilution Analysis

NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name

Fatty Acid Profile, Peroxisomal, S

Aliases Lists additional common names for a test, as an aid in searching

Adrenoleukodystrophy (ALD)
C22-C26, Fatty Acid Profile, Peroxisomal
Cerebrohepatorenal Syndrome
Long-Chain Fatty Acids (LCFA)
Peroxisomal, Fatty Acid Profile
Phytanic Acid
Phytanic Acid Oxidase Deficiency
Pristanic Acid
Refsum Disease
Very Long Chain Fatty Acids (VLCFA)
X-ALD (X-Linked Adrenoleukodystrophy)
X-Linked Adrenoleukodystrophy (X-ALD)
Zellweger Syndrome