Test Code ASMW Acid Sphingomyelinase, Leukocytes
Shipping Instructions
For optimal isolation of leukocytes, it is recommended the specimen arrive refrigerated within 6 days of collection to be stabilized. Collect specimen Monday through Thursday only and not the day before a holiday. Specimen should be collected and packaged as close to shipping time as possible.
Specimen Required
Container/Tube:
Preferred: Yellow top (ACD solution B)
Acceptable: Yellow top (ACD solution A) or lavender top (EDTA)
Specimen Volume: 6 mL
Collection Instructions: Send specimen in original tube. Do not aliquot.
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.
Useful For
Investigation of possible diagnosis of Niemann-Pick disease types A and B
This test is not recommended for carrier detection because of the wide range of enzymatic activities observed in carriers and noncarriers.
Testing Algorithm
For more information see Newborn Screen Follow-up for Acid Sphingomyelinase Deficiency
If the patient has abnormal newborn screening results for Niemann- Pick disease, refer to the appropriate American College of Medical Genetics and Genomics Newborn Screening ACT Sheet.(1)
Special Instructions
Method Name
Flow Injection Analysis-Tandem Mass Spectrometry (FIA-MS/MS)
Reporting Name
Acid Sphingomyelinase, LeukocytesSpecimen Type
Whole Blood ACDSpecimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood ACD | Refrigerated (preferred) | 6 days | |
Ambient | 6 days |
Reference Values
≥0.32 nmol/hour/mg protein
An interpretative report will be provided.
Interpretation
Values below the reference range are consistent with a diagnosis for Niemann-Pick types A and B.
When abnormal results are detected, a detailed interpretation is given, including an overview of the results and of their significance, a correlation to available clinical information, elements of differential diagnosis, recommendations for additional biochemical testing, and in vitro, confirmatory studies (enzyme assay, molecular analysis), name and phone number of key contacts who may provide these studies, and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.
Clinical Reference
1. Newborn Screening ACT Sheet [Decreased acid sphingomyelinase] Acid Sphingomyelinase Deficiency (ASMD). American College of Medical Genetics and Genomics; 2022. Revised May 2022. Accessed June 10, 2024. Available at www.acmg.net/PDFLibrary/Niemann-Pick.pdf
2. Elliott S, Buroker N, Cournoyer JJ, et al: Pilot study of newborn screening for six lysosomal storage diseases using Tandem Mass Spectrometry. Mol Genet Metab. 2016 Aug;118(4):304-309
3. Matern D, Gavrilov D, Oglesbee D, Raymond K, Rinaldo P, Tortorelli S:Â Newborn screening for lysosomal storage disorders. Semin Perinatol. 2015 Apr;39(3):206-216
4. Schuchman EH, Desnick RJ: Niemann-Pick disease types A and B: acid sphingomyelinase deficiencies. In: Valle D, Antonarakis S, Ballabio A, Beaudet A, Mitchell GA, eds. The Online Metabolic Bases of Inherited Disease. McGraw-Hill; 2019. Accessed May 26, 2021. Available athttps://ommbid.mhmedical.com/content.aspx?sectionid=225545671&bookid=2709
5. Wasserstein MP, Schuchman EH: Acid sphingomyelinase deficiency. In: Adam MP, Ardinger HH, Pagon RA, et al, eds. GeneReviews. [Internet]. University of Washington, Seattle; 2006. Updated February 25, 2021. Accessed May 26, 2021. Available at www.ncbi.nlm.nih.gov/books/NBK1370/
6. Schuchman EH, Desnick RJ: Types A and B Niemann-Pick disease. Mol Genet Metab. 2017 Jan-Feb;120(1-2)27-33
Day(s) Performed
Preanalytical processing: Monday through Saturday.
Assay performed: Monday, Wednesday
Report Available
5 to 10 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest 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
82657
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ASMW | Acid Sphingomyelinase, Leukocytes | 24101-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
606264 | Acid Sphingomyelinase, Leukocytes | 24101-8 |
606265 | Interpretation | 59462-2 |
606266 | Reviewed By | 18771-6 |