Test ID HEX4 Glucotetrasaccharides, Random, Urine
Ordering Guidance
Additional Testing Requirements
When requested for the diagnosis of Pompe disease (GSD II), glucotetrasaccharide concentrations in urine need to be interpreted in light of the clinical presentation and other laboratory tests, such as blood creatine kinase, alpha-glucosidase (GAA) activity, and GAA genotype.
Necessary Information
Patient's age and reason for testing are required.
Specimen Required
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Container/Tube: Plastic, 5-mL urine tube
Specimen Volume: 3 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Useful For
Diagnosing Pompe disease, when used in conjunction with acid alpha-glucosidase enzyme activity assays and molecular genetic analysis of the GAA gene
Monitoring Pompe patients on enzyme replacement therapy
May support the diagnosis and monitoring of other glycogen storage disorders; however, glucotetrasaccharide (Glc4) excretion appears to be less consistently elevated in glycogen storage disorders other than Pompe disease
This test is not useful for carrier screening
Testing Algorithm
See Newborn Screen Follow-up for Pompe Disease in Special Instructions.
Special Instructions
Method Name
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Glucotetrasaccharides, USpecimen Type
UrineSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Frozen (preferred) | 87 days | |
Refrigerated | 28 days | ||
Ambient | 14 days |
Reference Values
≤14 months: ≤14.9 mmol/mol Cr
≥15 months: ≤4.0 mmol/mol Cr
Day(s) Performed
Wednesday
Report Available
7 to 14 daysPerforming Laboratory

Test Classification
This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82542
82570
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
HEX4 | Glucotetrasaccharides, U | 53868-6 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
64174 | Glucotetrasaccharides, U | 53868-6 |
BG710 | Reason for Referral | 42349-1 |
BA2896 | Intepretation (HEX4) | 59462-2 |
BA2897 | Reviewed By | 18771-6 |