Test Catalog

Test ID: CRDPP    
Creatine Disorders Panel, Plasma

Useful For Suggests clinical disorders or settings where the test may be helpful

Evaluation of patients with a clinical suspicion of arginine:glycine amidinotransferase deficiency and guanidinoacetate methyltransferase deficiency.


This test is not useful for the diagnosis of creatine transporter deficiency.

Genetics Test Information Provides information that may help with selection of the correct genetic test or proper submission of the test request

Depletion of cerebral creatine occurs in all 3 types of creatine deficiency syndromes (CDS): arginine:glycine amidinotransferase deficiency, guanidinoacetate methyltransferase deficiency, and creatine transporter deficiency.


Measurement of guanidinoacetate, creatine, and creatinine along with associated analyte ratios in plasma and urine distinguishes among the types of creatine deficiency syndromes.


Treatment with oral creatine supplementation is effective in some types of CDS.


Creatine supplementation may impact reliability of test results.

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Special Instructions Library of PDFs including pertinent information and forms related to the test

Method Name A short description of the method used to perform the test

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

NY State Available Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name Lists a shorter or abbreviated version of the Published Name for a test

Creatine Disorders Panel, P

Aliases Lists additional common names for a test, as an aid in searching

AGAT (Arginine:Glycine Amidinotransferase) Deficiency
Arginine:Glycine Amidinotransferase Deficiency (AGAT)
Creatine disorders
Creatine plasma
Creatine/creatinine ratio plasma
Creatinine plasma
GAMT (Guanidinoacetate Methyltransferase) Deficiency
Guanidinoacetate Methyltransferase (GAMT) Deficiency
Guanidinoacetic acid (GAA)
L-Arginine:Glycine Amidinotransferase Deficiency (AGAT)