Home
HelpTest Code Billings Clinic: 8956 Mayo: ARSU Arylsulfatase A, 24 Hour, Urine
Reporting Name
Arylsulfatase A, UPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Useful For
Detection of arylsulfatase A deficiency using urine specimens
This test is not suitable for carrier detection.
Method Name
Colorimetric, Enzyme Assay
Ordering Guidance
Leukocytes are the preferred screening specimen for metachromatic leukodystrophy. The preferred test to rule-out metachromatic leukodystrophy is ARSAW / Arylsulfatase A, Leukocytes.
Shipping Instructions
Specimen must be received at least 1 day prior to assay day for processing.
Necessary Information
24-Hour volume (in milliliters) is required.
Specimen Required
Supplies: Urine Tubes, 10 mL (T068)
Container/Tube: Plastic, 10-mL tube
Specimen Volume: 6 mL
Collection Instructions:
1. Collect a 24-hour urine specimen.
2. No added preservative.
3. Refrigerate specimen during collection.
Additional Information: For multiple collections see Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens.
Specimen Type
UrineSpecimen Minimum Volume
2.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated | 14 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
≥19 nmol/h/mL
Note: Results from this assay may not reflect carrier status because of individual variation of arylsulfatase A enzyme levels. Low normal values may be due to the presence of pseudodeficiency or carrier alleles. Patients with these depressed levels may be phenotypically normal.
Interpretation
Reduced levels of arylsulfatase A are seen in patients with metachromatic leukodystrophy (MLD).
Individuals with pseudodeficiency of arylsulfatase A can have results in the affected range but are otherwise unaffected with MLD.
Abnormal results should be confirmed using CTSU / Ceramide Trihexosides and Sulfatides, Random, Urine. If molecular confirmation is desired, consider molecular genetic testing of ARSA (CGPH / Custom Gene Panel, Hereditary, Next-Generation Sequencing, Varies; specify Gene List ID: IEMCP-WHFH2K).
Day(s) Performed
Tuesday
Report Available
3 to 9 daysTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
84311
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| ARSU | Arylsulfatase A, U | 42726-0 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 8777 | Arylsulfatase A, U | 42726-0 |
| 37423 | Interpretation (ARSU) | 59462-2 |
| 37413 | Reviewed By | 18771-6 |
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. Biochemical Genetics Patient Information (T602)
3. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Special Instructions
Testing Algorithm
For information see Lysosomal Disorders Diagnostic Algorithm, Part 2