Catalog ID OXYWB Oxysterols, Blood
Useful For
Investigating a possible diagnosis of acid sphingomyelinase deficiency, also known as Niemann-Pick disease type A or B, using dried blood spots created from a whole blood specimen
This test is not recommended for diagnosis of Niemann-Pick type C (NPC). If NPC is suspected, consider plasma oxysterols.
This test is not useful for the identification of carriers
Ordering Guidance
Based on internal validation studies, this test using dried blood spots created from a whole blood specimen is less clinically sensitive and specific for diagnosing Niemann-Pick type C (NPC) (75% and 89%, respectively) than using plasma (98%). If there is a strong clinical suspicion for NPC, order OXNP / Oxysterols, Plasma.
This test is also available as a part of a panel, see HSMWB / Hepatosplenomegaly Panel, Blood. If this test (OXYWB) is ordered with either GPSYW / Glucopsychosine, Blood or CTXWB / Cerebrotendinous Xanthomatosis, Blood, the individual tests will be canceled and HSMWB ordered.
Specimen Required
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Green top (sodium heparin, lithium heparin) or yellow top (ACD B)
Specimen Volume: 1 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Collect 1.0 mL blood in Purple top tube.
Reference Values
Cholestane-3-beta,5-alpha,6-beta-triol
Cutoff: ≤0.800 nmol/mL
Lyso-sphingomyelin
Cutoff: ≤0.100 nmol/mL
Day(s) Performed
Tuesday, Thursday
Reporting Name
Oxysterols, BSpecimen Type
Whole bloodSpecimen Minimum Volume
0.25 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole blood | Refrigerated (preferred) | 72 hours |
| Ambient | 48 hours |
Reject Due To
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
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.Secondary ID
113429CPT Code Information
82542
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| OXYWB | Oxysterols, B | 92738-4 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| BA4354 | Interpretation (OXYWB) | 59462-2 |
| BA4352 | Cholestane-3beta,5alpha,6beta-triol | 92756-6 |
| BA4353 | Lyso-sphingomyelin | 92748-3 |
| BA4355 | Reviewed By | 18771-6 |
Testing Algorithm
If the patient has abnormal newborn screening results for acid sphingomyelinase deficiency, also called Niemann-Pick type A or B disease, refer to the appropriate American College of Medical Genetics and Genomics Newborn Screening ACT Sheet.(1)
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.