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HelpOrder Code PSYR Psychosine, Whole Blood
Ordering Guidance
This test is recommended for individuals of all ages, infancy through adulthood, for diagnosis or long-term monitoring of patients who have been treated or who are at risk of developing Krabbe disease.
If a result is needed within 24 hours, order PSY / Psychosine, Blood Spot.
Shipping Instructions
Must be sent refrigerated.
Necessary Information
1. Patient’s age is required.
2. Date of hematopoietic stem cell transplantation (HSCT), if performed.
Specimen Required
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Green top (sodium heparin, lithium heparin)
Specimen Volume: 2 mL
Useful For
Aiding in the biochemical diagnosis of Krabbe disease using whole blood specimens
Follow-up of individuals affected with Krabbe disease
Follow-up testing after an abnormal newborn screening result for Krabbe disease
Monitoring of individuals at risk to develop late onset Krabbe disease
Monitoring of individuals with Krabbe disease after hematopoietic stem cell transplantation
Genetics Test Information
Krabbe disease (globoid cell leukodystrophy) is an autosomal recessive lysosomal disorder caused by deficient activity of the enzyme galactocerebrosidase.
Krabbe disease is clinically variable; infantile-onset Krabbe disease is the most severe type, with rapid neurological regression resulting in early death.
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Psychosine, RBCSpecimen Type
Whole bloodSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Whole blood | Refrigerated | 7 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
Normal <5 pmol/g Hb
Method Description
Psychosine is extracted from washed red blood cells and quantified using an isotopically labeled internal standard by liquid chromatography tandem mass spectrometry.(Unpublished Mayo method)
Day(s) Performed
Tuesday, Thursday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
82542
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Testing Algorithm
If the patient has abnormal newborn screening result for Krabbe disease, immediate action should be taken. Refer to the appropriate American College of Medical Genetics and Genomics Newborn Screening ACT Sheet.(1,2)