Creatine Biosynthesis Disorders: Creatine/GAA Analysis (Urine)
Creatine Biosynthesis Disorders: Creatine/GAA Analysis (Urine)
Creatine biosynthesis disorders can be separated based on urine testing for guanidinoacetate (GAA) and creatine. Patients with AGAT deficiency show a low urinary GAA level while patients with GAMT have an elevated GAA level.
Clinical Information
Both AGAT and GAMT are autosomal recessive disorders and are characterized by intellectual disability, speech delay and epilepsy. GAMT deficiency can also present with a dystonic hyperkinetic movement disorder.
Technical Information
Creatine and guanidinoacetate are measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS).
Specimen Requirements
Urine is the sample type for this test, and requires a minimum of 2 mL random catch urine.
Transport Instructions
The urine specimen should be frozen after collection and shipped frozen, preferably on dry ice.
Associated Tests
Connect With Our Experts
Call 1-800-473-9411 to speak with our team of laboratory genetic counselors for questions or additional information.
Robin Fletcher, MS, CGC
Falecia Thomas, MS, CGC
Alex Finley, MS, CGC