PSY - Overview: Psychosine, Blood Spot

Test Catalog

Test Name

Test ID: PSY    
Psychosine, Blood Spot

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

Quantification of psychosine (galactosylsphingosine) in dried blood spots to support the biochemical diagnosis and follow-up of individuals affected with Krabbe disease

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

This test is used as a second-tier assay for newborn screens with reduced GALC (galactocerebrosidase) activity and to diagnose and monitor patients with Krabbe disease.


Krabbe disease (globoid cell leukodystrophy) is an autosomal recessive lysosomal storage disorder caused by an enzyme deficiency of galactocerebrosidase (GALC).


Although Krabbe disease is clinically variable, the most common and severe form of the disorder is early infantile onset that presents with rapid neurological regression and results in early death.


Elevations in psychosine support a diagnosis of Krabbe disease; therefore, psychosine quantitation is a useful biomarker in determining if an individual has active disease, to monitor disease progression, or treatment response.

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

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

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

Psychosine, BS

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

Krabbe disease