Beta-Glucuronidase, Blood Spot
Use
This test supports the biochemical diagnosis of mucopolysaccharidosis VII (MPS VII, also known as Sly syndrome). It is particularly useful for diagnosing individuals with clinical signs and symptoms suggestive of MPS VII. Abnormal findings from this test indicate an enzyme deficiency, at which point additional biochemical or molecular testing is recommended for confirming a diagnosis. The test is not effective for determining carrier status for MPS VII.
Special Instructions
Patient's age and reason for testing are required prior to test submission. This test is available for order by New York State clients and requires informed consent for genetic testing, which must be documented on the request form or electronic order.
Limitations
This test is not adequate for determining carrier status for MPS VII. Enzyme levels may be normal in individuals who have undergone enzyme replacement therapy or hematopoietic stem cell transplant. Abnormal results from this assay alone cannot definitively diagnose a disease; further biochemical or molecular analyses are required to verify a diagnosis. Individuals with certain pseudodeficiency alleles might show reduced enzyme activity which can impact test results.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 79457-8
- 79457-8
- 42349-1
- 59462-2
- 18771-6
Result Turnaround Time
3-9 days
Related Documents
For more information, please review the documents below
Specimen
Dried Blood Spot
Volume
Not provided
Minimum Volume
Not provided
Container
Blood Spot Collection Card; Acceptable: Whatman Protein Saver 903 Paper, PerkinElmer 226 filter paper, Munktell filter paper
Collection Instructions
Preferred specimen type is blood spot. Alternative blood collection for patients older than 1 year is a fingerstick. See 'How to Collect a Dried Blood Spot Sample' for details. Ensure at least 2 spots are complete. Let blood dry at ambient temperature for at least 3 hours, do not expose to heat or direct sunlight, do not stack wet specimens. Keep specimen dry.
Storage Instructions
Refrigerated (preferred 60 days), Ambient (7 days), Frozen (60 days)
Causes for Rejection
Blood spot specimen with serum rings or multiple layers, insufficient specimen, unapproved filter papers.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 60 days |
| Frozen | 60 days |