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Creatine Biosynthesis Disorders Panel, Urine
- Ordering Info
To view specimen requirements and codes please Select a regional laboratory.Not sure which laboratory serves your office? Call us 866-MYQUEST (866-697-8378)
82540, 82570, 82542
**IMPORTANT: CPT Code is informational only; obtain the Test Code for ordering.
Guanidinoacetate, Creatine, Creatinine, Creatine/Creatinine
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)
The intended use for this test is as a means of evaluating patients with a suspected inherited disorder of creatine metabolism. The cerebral creatine deficiency syndromes (CCDS), inborn errors of creatine metabolism, include the two creatine biosynthesis disorders (guanidinoacetate methyltransferase [GAMT] deficiency and L-arginine: glycine amidinotransferase [AGAT or GATM] deficiency), and the X-linked creatine transporter [SLC6A8] deficiency. Intellectual disability and seizures are common to all three CCDS. The majority of individuals with GAMT deficiency have a behavior disorder that can include autistic behaviors and self-mutilation; a significant proportion have pyramidal/ extrapyramidal findings. Onset is between the ages of three months and three years. The phenotype of SLC6A8 deficiency in affected males ranges from mild intellectual disability and speech delay to severe intellectual disability, seizures, and behavior disorder, with age at diagnosis ranging from 2 to 66 years. Females heterozygous for SLC6A8 deficiency may have learning and behavior problems.
Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.
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