Classic view of this page
Alpha-L-Iduronidase, Leukocytes
Clinical Genetic Test
Help
offered by
Mayo Clinic Laboratories
View lab's test page
LinkOut
GTR Test Accession: Help GTR000603775.2
INHERITED DISEASEDYSMORPHOLOGYOPHTHALMOLOGY ... View more
Last updated in GTR: 2023-04-07
View version history
Last annual review date for the lab: 2024-05-28 LinkOut
At a Glance
Test purpose: Help
Diagnosis
Conditions (1): Help
Mucopolysaccharidosis type 1
Analytes (1): Help
Alpha-L-Iduronidase
Methods (1): Help
Biochemical Genetics - Enzyme assay: Flow Injection Analysis-Tandem Mass Spectrometry (FIA-MS/MS)
Target population: Help
Diagnosis of mucopolysaccharidosis I This test is not useful for …
Clinical validity: Help
Not provided
Clinical utility: Help
Establish or confirm diagnosis
Ordering Information
Offered by: Help
Mayo Clinic Laboratories
View lab's website
View lab's test page
Test short name: Help
IDUAW
Specimen Source: Help
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • Licensed Dentist
  • Licensed Physician
  • Nurse Practitioner
  • Physician Assistant
  • Public Health Mandate
  • Registered Nurse
Lab contact: Help
Gisele (Gessi) Bentz Pino, MS, CGC, Certified Genetic counselor, CGC, Genetic Counselor
[email protected]
1-800-533-1710
Contact Policy: Help
Laboratory can only accept contact from health care providers. Patients/families are encouraged to discuss genetic testing options with their health care provider.
How to Order: Help
https://www.mayocliniclabs.com/test-catalog/overview/606276#Specimen
Order URL
Test development: Help
Test developed by laboratory (no manufacturer test name)
Informed consent required: Help
Based on applicable state law
Pre-test genetic counseling required: Help
Decline to answer
Post-test genetic counseling required: Help
Decline to answer
Recommended fields not provided:
Test strategy
Conditions Help
Total conditions: 1
Condition/Phenotype Identifier
Test Targets
Analytes Help
Total analytes: 1
Analyte Associated Condition
Methodology
Total methods: 1
Method Category Help
Test method Help
Instrument *
Enzyme assay
Flow Injection Analysis-Tandem Mass Spectrometry (FIA-MS/MS)
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis
Clinical utility: Help
Establish or confirm diagnosis
View citations (1)

Target population: Help
Diagnosis of mucopolysaccharidosis I This test is not useful for determining carrier status.
View citations (3)
  • Guidelines for the management of mucopolysaccharidosis type I. Martins AM, et al. J Pediatr. 2009;155(4 Suppl):S32-46. doi:10.1016/j.jpeds.2009.07.005. PMID: 19765409.
  • Clarke LA, Atherton AM, Burton BK, Day-Salvatore DL, Kaplan P, Leslie ND, Scott CR, Stockton DW, Thomas JA, Muenzer J. Mucopolysaccharidosis Type I Newborn Screening: Best Practices for Diagnosis and Management. J Pediatr. 2017;182:363-370. doi:10.1016/j.jpeds.2016.11.036. Epub 2016 Dec 07. PMID: 27939258.
  • Neufeld EF, Muenzer J: The mucopolysaccharidoses. In: Valle D, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA. eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed March 23, 2022. Available at https://ommbid.mhmedical.com/content.aspx?sectionid=225544161
Recommended fields not provided:
Clinical validity, What is the protocol for interpreting a variation as a VUS?, Are family members with defined clinical status recruited to assess significance of VUS without charge?, Will the lab re-contact the ordering physician if variant interpretation changes?, Is research allowed on the sample after clinical testing is complete?, Sample negative report, Sample positive report
Technical Information
Test Procedure: Help
The specimens are incubated with a mix of substrate and internal standard for acid sphingomyelinase, beta-glucocerebrosidase, acid alpha-glucosidase, alpha-galactosidase, galactocerebrosidase, and alpha-L-iduronidase. The sample is then purified by liquid-liquid extraction. The extract is evaporated and reconstituted before analysis by tandem mass spectrometry.(Unpublished Mayo method)
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
Accuracy was assessed by analysis of positive and negative specimens; all samples were clinically concordant. Intra assay precision was performed at 3 levels: CV results ranged from 3%-3% (N=20 each). Inter assay precision was performed at 3 levels: CV results ranged from 6%-7% (N=20 each). The analytical measurement range is … View more
Assay limitations: Help
The presence of a pseudodeficiency allele may cause reduced activity of alpha-L-iduronidase in the artificial substrate used in this assay. Enzyme levels may be normal in individuals receiving enzyme replacement therapy or who have undergone hematopoietic stem cell transplant.
Proficiency testing (PT):
Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Intra-Laboratory

Description of PT method: Help
Intra-laboratory alternative assessment of performance through quality control or patient blind testing

Description of internal test validation method: Help
This test was laboratory developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements.
Recommended fields not provided:
Test Confirmation, Citations to support assay limitations, Citations to support internal test validation method, Citations for Analytical validity, PT Provider, Major CAP category, CAP category, CAP test list
Regulatory Approval
FDA Review: Help
Category: FDA exercises enforcement discretion
Additional Information

IMPORTANT NOTE: NIH does not independently verify information submitted to GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.