Test Code SXDBS Sorbitol and Xylitol, Quantitative, Blood Spot
Ordering Guidance
This is a test for diagnosis and treatment monitoring for sorbitol dehydrogenase (SORD) deficiency-related peripheral neuropathy.
Necessary Information
Biochemical Genetics Patient Information (T602) is recommended, but not required, to be filled out and sent with the specimen to aid in the interpretation of test results.
Specimen Required
Fasting: 8 hours, required. Infants should not fast overnight; collect just before next feeding.
Supplies: Card-Blood Spot Collection (Filter Paper) (T493)
Container/Tube:
Preferred: Card-Blood Spot Collection (Filter Paper)
Acceptable: PerkinElmer 226 filter paper, Munktell filter paper, Whatman protein Saver 903 paper, local newborn screening card, or blood collected in tubes containing EDTA (preferred) or sodium heparin and dried on filter paper.
Specimen Volume: 2 Blood spots
Collection Instructions:
1. An alternative blood collection option for a patient older than 1 year is a fingerstick. For detailed instructions, see How to Collect a Dried Blood Spot Sample.
2. Completely fill at least 2 circles on the filter paper card (approximately 100 microliters blood per circle).
3. Let blood dry on filter paper at ambient temperature in a horizontal position for a minimum of 3 hours.
4. Do not expose specimen to heat or direct sunlight.
5. Do not stack wet specimens.
6. Keep specimen dry.
Additional Information:
1. For collection instructions, see Blood Spot Collection Instructions
2. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777)
3. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800)
Forms
Useful For
Screening and treatment monitoring for sorbitol dehydrogenase deficiency-related neuropathy
Method Name
Gas Chromatography Mass Spectrometry (GC-MS) Stable Isotope Dilution Analysis
Reporting Name
Sorbitol and Xylitol, Quant, DBSSpecimen Type
Blood SpotSpecimen Minimum Volume
1 Blood spot
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Blood Spot | Ambient (preferred) | 31 days | FILTER PAPER |
| Frozen | 90 days | FILTER PAPER | |
| Refrigerated | 90 days | FILTER PAPER |
Reject Due To
| Blood spot specimen that shows serum rings or has multiple layers | Reject |
| Insufficient specimen | Reject |
| Non-approved filter papers | Reject |
Reference Values
Sorbitol: ≤30.0 nmol/mL
Xylitol: ≤10.0 nmol/mL
Day(s) Performed
Friday
Report Available
5 to 11 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test 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
82542
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| SXDBS | Sorbitol and Xylitol, Quant, DBS | In Process |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 623692 | Interpretation | 59462-2 |
| 623690 | Sorbitol | In Process |
| 623691 | Xylitol | In Process |
| 623693 | Reviewed By | 18771-6 |