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Creatine Disorders Panel, P
Clinical Genetic Test
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offered by
Mayo Clinic Laboratories
View lab's test page
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GTR Test Accession: Help GTR000613147.2
INHERITED DISEASEMETABOLIC DISEASENERVOUS SYSTEM ... View more
Last updated in GTR: 2024-05-20
View version history
Last annual review date for the lab: 2024-05-28 LinkOut
At a Glance
Test purpose: Help
Diagnosis
Conditions (3): Help
Arginine:glycine amidinotransferase deficiency; Creatine transporter deficiency; Deficiency of guanidinoacetate methyltransferase
Analytes (3): Help
Creatine, Creatinine and Cr/Crn ratio; Guanidinoacetate; Guanidinoacetate, Creatine, Creatinine and Cr/Crn ratio
Methods (1): Help
Biochemical Genetics - Analyte: Liquid chromatography-tandem mass spectrometry (LC-MS/MS)
Target population: Help
Evaluating patients with a clinical suspicion of arginine:glycine amidinotransferase deficiency,guanidinoacetate …
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
CRDPP
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
Test Order Code: Help
CRDPP
View other test codes
LOINC codes: Help
**LOINC codes notice
CPT codes: Help
**AMA CPT codes notice

Copyright: 2023 American Medical Association. All rights reserved.

Lab contact: Help
Gisele (Gessi) Bentz Pino, MS, CGC, Certified Genetic counselor, CGC, Genetic Counselor
biochemicalgenetics@mayo.edu
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/606130#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: 3
Condition/Phenotype Identifier
Test Targets
Analytes Help
Total analytes: 3
Analyte Associated Condition
Methodology
Total methods: 1
Method Category Help
Test method Help
Instrument *
Analyte
Liquid chromatography-tandem mass spectrometry (LC-MS/MS)
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis
Clinical utility: Help
Establish or confirm diagnosis
View citations (2)
  • Clark JF, Cecil KM. Diagnostic methods and recommendations for the cerebral creatine deficiency syndromes. Pediatr Res. 2015;77(3):398-405. doi:10.1038/pr.2014.203. Epub 2014 Dec 18. PMID: 25521922.
  • Sanders K, Peck D, Bentz Pino G, Studinski Jones A, White A, Gavrilov D, Matern D, Oglesbee D, Schultz M, Tortorelli S, Hall PL. SLC6A8 creatine transporter deficiency can be detected by plasma creatine and creatinine concentrations. Mol Genet Metab. 2024;142(1):108455. doi:10.1016/j.ymgme.2024.108455. Epub 2024 Mar 24. PMID: 38531184.

Target population: Help
Evaluating patients with a clinical suspicion of arginine:glycine amidinotransferase deficiency,guanidinoacetate methyltransferase deficiency, and creatine transporter deficiency using plasma specimens This test is not useful for the diagnosis of creatine transporter deficiency.
View citations (5)
  • Cerebral creatine deficiency syndromes: clinical aspects, treatment and pathophysiology. Stockler S, et al. Subcell Biochem. 2007;46:149-66. doi:10.1007/978-1-4020-6486-9_8. PMID: 18652076.
  • Clark JF, Cecil KM. Diagnostic methods and recommendations for the cerebral creatine deficiency syndromes. Pediatr Res. 2015;77(3):398-405. doi:10.1038/pr.2014.203. Epub 2014 Dec 18. PMID: 25521922.
  • Sharer JD, Bodamer O, Longo N, Tortorelli S, Wamelink MM, Young S. Laboratory diagnosis of creatine deficiency syndromes: a technical standard and guideline of the American College of Medical Genetics and Genomics. Genet Med. 2017;19(2):256-263. doi:10.1038/gim.2016.203. Epub 2017 Jan 05. PMID: 28055022.
  • Sanders K, Peck D, Bentz Pino G, Studinski Jones A, White A, Gavrilov D, Matern D, Oglesbee D, Schultz M, Tortorelli S, Hall PL. SLC6A8 creatine transporter deficiency can be detected by plasma creatine and creatinine concentrations. Mol Genet Metab. 2024;142(1):108455. doi:10.1016/j.ymgme.2024.108455. Epub 2024 Mar 24. PMID: 38531184.
  • Mercimek-Mahmutoglu S, Salomons GS. Creatine deficiency syndromes. In: Adam MP, Mirzaa GM, Pagon RA, et al. eds. GeneReviews [Internet]. University of Washington, Seattle; 2009. Updated February 10, 2022. Accessed March 30, 2023. Available at www.ncbi.nlm.nih.gov/books/NBK3794/
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
A plasma sample is combined with stable isotope-labeled internal standards and acetonitrile. After centrifugation, an aliquot of this diluted sample is analyzed by injection onto liquid chromatography columns that separate the analytes from the bulk of the stable isotope dilution in the positive electrospray selected reaction monitoring mode using the … View more
View citations (2)
  • Analysis of guanidinoacetate and creatine by isotope dilution electrospray tandem mass spectrometry. Bodamer OA, et al. Clin Chim Acta. 2001;308(1-2):173-8. doi:10.1016/s0009-8981(01)00480-6. PMID: 11412830.
  • Determination of guanidinoacetate and creatine in urine and plasma by liquid chromatography-tandem mass spectrometry. Cognat S, et al. Clin Chem. 2004;50(8):1459-61. doi:10.1373/clinchem.2004.034538. PMID: 15277360.
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
Recovery was used to assess accuracy; mean recovery was 89% for creatinine, 98% for guanidinoacetate, and 92% for creatine. Intra assay precision was performed at 3 levels: CV results ranged from 2.6%-9.9% (N=20 each). Inter assay precision was performed at 3 levels: CV results ranged from 6.9%-12.5% (N=20 each). The … View more
Assay limitations: Help
Creatine supplementation will cause falsely elevated creatine results and falsely decreased guanidinoacetate results. Guanidinoacetate can be elevated in patients with urea cycle defects.
Proficiency testing (PT):
Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
European Research Network for the Evaluation and Improvement of Screening Diagnosis and Treatment of Inherited Metabolic Disorders - External Quality Assessment Schemes, ERNDIM EQAS

Description of PT method: Help
Formal PT program

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, 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.