Order Code GPSYW Glucopsychosine, Blood
Ordering Guidance
This test is also available as a part of panel; see HSMWB / Hepatosplenomegaly Panel, Blood. If this test (GPSYW) is ordered with either CTXWB / Cerebrotendinous Xanthomatosis, Blood or OXYWB / Oxysterols, Blood, the individual tests will be canceled and HSMWB ordered.
Specimen Required
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Green top (sodium heparin, lithium heparin) or yellow top (ACD B)
Specimen Volume: 1 mL
Collection Instructions: Send whole blood in original vial. Do not aliquot.
Forms
1. Biochemical Genetics Patient Information (T602)
2. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Useful For
Second-tier test when newborn screening results with reduced beta-glucosidase (GBA) activity are identified
Diagnosis and monitoring of patients with Gaucher disease using whole blood specimens
Supporting the biochemical diagnosis of Gaucher disease
Monitoring a patient's response to treatment
This test is not useful for identifying carriers of GBA variants.
Special Instructions
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Glucopsychosine, BSpecimen Type
Whole bloodSpecimen Minimum Volume
0.25 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Whole blood | Refrigerated (preferred) | 72 hours |
Ambient | 48 hours |
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Reference Values
Cutoff: ≤0.040 nmol/mL
Method Description
Whole blood is spotted on filter paper and dried overnight. A 3-mm dried blood spot is extracted with internal standard. The extract is subjected to liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. The MS/MS is operated in the multiple reaction monitoring positive mode to follow the precursor to product species transitions for each analyte and internal standard. The ratio of the extracted peak areas to internal standard determined by the LC-MS/MS is used to calculate the concentration of in the sample.(Unpublished Mayo method)
Day(s) Performed
Tuesday
Performing Laboratory

CPT Code Information
82542
Genetics Test Information
Gaucher disease is an autosomal recessive lysosomal storage disorder caused by deficient beta-glucosidase activity.
There are 3 described types of Gaucher disease with varying clinical presentations generally distinguished based on whether there is central nervous system involvement.
Glucopsychosine (glucosylsphingosine: lyso-GL1) is elevated in symptomatic patients and supports a diagnosis of Gaucher disease.
Testing Algorithm
For more information see Newborn Screen Follow-up for Gaucher Disease
If the patient has abnormal newborn screening results for Gaucher disease, refer to the appropriate American College of Medical Genetics and Genomics Newborn Screening ACT Sheet.(1)