Glucopsychosine, Blood Spot
Use
This test is primarily useful for diagnosing and monitoring patients with Gaucher disease using dried blood spot specimens. It also serves as a second-tier test when newborn screening results indicate reduced beta-glucosidase (GBA) activity. Monitoring a patient's response to treatment is another significant clinical use. It is important to note that this test is not useful for identifying carriers of GBA1 variants, as Gaucher disease is characterized by deficient beta-glucosidase activity resulting in the accumulation of glucopsychosine (glucosylsphingosine: lyso-GL1) in symptomatic patients, thus supporting a diagnosis of Gaucher disease.
Special Instructions
This test is also part of the Hepatosplenomegaly Panel, Blood Spot. If ordered with CTXBS or OXYBS, these individual tests will be canceled and HSMBS will be ordered. A Biochemical Genetics Test Request form should be sent with the specimen if not ordering electronically. Blood spots should be dried in a horizontal position at ambient temperature for at least 3 hours. Avoid exposure to heat or direct sunlight and do not stack wet specimens. At least one spot should remain complete and unpunched.
Limitations
Patients with Gaucher disease may present with normal concentrations of glucopsychosine (lyso-GL1), potentially leading to challenges in diagnosis. The test is not intended for carrier identification, limiting its scope for genetic counseling of asymptomatic individuals.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 92752-5
- 92752-5
- 18771-6
- 59462-2
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
2 Blood spots
Minimum Volume
1 Blood spot
Container
Preferred: Blood Spot Collection (Filter Paper); Acceptable: Whatman Protein Saver 903 filter paper, PerkinElmer 226 filter paper, Munktell filter paper, Postmortem Screening card, or collected with sodium heparin, lithium heparin, ACD-B or EDTA containing devices
Collection Instructions
Let blood dry completely on filter paper at ambient temperature in a horizontal position for a minimum of 3 hours. At least 1 spot should be complete, (ie, unpunched). Do not expose specimen to heat or direct sunlight. Do not stack wet specimens. Keep specimen dry.
Causes for Rejection
Blood spot specimen that shows serum rings or has multiple layers; Insufficient specimen
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 10 days |
| Refrigerated | 10 days |
| Frozen | 59 days |