Glucotetrasaccharides, Random, Urine
Use
Used to aid in diagnosing Pompe disease (glycogen storage disorder type II) when combined with acid alpha‑glucosidase enzyme activity assays and molecular genetic analysis of the GAA gene; also used to monitor patients with Pompe disease on enzyme replacement therapy; may support diagnosis and monitoring of other glycogen storage disorders, though glucotetrasaccharide excretion is less consistently elevated in disorders other than Pompe disease; not useful for carrier screening.
Special Instructions
Additional testing requirements: interpretation requires consideration of clinical presentation and other lab tests such as blood creatine kinase, alpha‑glucosidase activity, and GAA genotype. Necessary information required: patient's age and reason for testing. If not ordering electronically, complete and send Biochemical Genetics Test Request (T798).
Limitations
Elevated glucotetrasaccharide may be due to dietary artifacts, particularly carbohydrate ingestion; normal levels may occur in late‑onset Pompe disease; enzyme or molecular analysis is required to confirm diagnosis.
New York Approved
Methodology
Mass Spectrometry (LC‑MS/MS)
Biomarkers
LOINC Codes
- 53868-6
- 53868-6
Result Turnaround Time
4-10 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
3 mL
Minimum Volume
1 mL
Container
Plastic, 5‑mL urine tube
Collection Instructions
Collect a random urine specimen; no preservative.
Causes for Rejection
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 28 days |
| Frozen | 87 days |