Creatine Disorders Panel, Blood
Test Mnemonic
GUANID
CPT Codes
- 82542 - QTY (1)
- 82540 - QTY (1)
Aliases
- Guanidinoacetate
Includes
- Creatine
- Guanidinoacetic Acid
Performing Laboratory
ARUP
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1 mL | Plasma | EDTA (Lavender) | Frozen | Separate from cells ASAP or within 2 hours of collection, transfer into standard aliquot tube, and freeze immediately. Clinical information is necessary for appropriate interpretation. Additional required information includes age, gender, diet (e.g., TPN therapy), drug therapy, and family history. Please submit Patient History for Creatine Deficiency Syndromes Testing form AND Biochemical Genetics Patient History form with specimen. | |
| 1 mL | Plasma | Sodium or Lithium heparin (Green) | Frozen | Separate from cells ASAP or within 2 hours of collection, transfer into standard aliquot tube, and freeze immediately. Clinical information is necessary for appropriate interpretation. Additional required information includes age, gender, diet (e.g., TPN therapy), drug therapy, and family history. Please submit Patient History for Creatine Deficiency Syndromes Testing form AND Biochemical Genetics Patient History form with specimen. | |
| 1 mL | Serum | No additive (Red) | Frozen | Separate from cells ASAP or within 2 hours of collection, transfer into standard aliquot tube, and freeze immediately. Clinical information is necessary for appropriate interpretation. Additional required information includes age, gender, diet (e.g., TPN therapy), drug therapy, and family history. Please submit Patient History for Creatine Deficiency Syndromes Testing form AND Biochemical Genetics Patient History form with specimen. | |
| 1 mL | Serum | SST (Gold) | Frozen | Separate from cells ASAP or within 2 hours of collection, transfer into standard aliquot tube, and freeze immediately. Clinical information is necessary for appropriate interpretation. Additional required information includes age, gender, diet (e.g., TPN therapy), drug therapy, and family history. Please submit Patient History for Creatine Deficiency Syndromes Testing form AND Biochemical Genetics Patient History form with specimen. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 0.2 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | Unacceptable |
| Refrigerated | 1 week |
| Frozen | 2 weeks (Avoid repeated freeze/thaw cycles) |
Days Performed
Mon
Turnaround Time
3 - 10 days
Methodology
| Name | Description |
|---|---|
| Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) |
Reference Range
| Creatine, Ser/Pl | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | < or = 10 years: 37.0 - 117.0 | umol/L | Normal | > or = 11 years: 9.0 - 90.0 | umol/L |
Special Info
Clinical information is necessary for appropriate interpretation. Additional required information includes age, gender, diet (e.g., TPN therapy), drug therapy, and family history. Please submit Patient History for Creatine Deficiency Syndromes Testing form AND Biochemical Genetics Patient History form with specimen. Specimens exposed to more than one freeze/thaw cycle will be rejected. This test is New York DOH approved.
Clinical Info
Initial test to diagnose or rule out creatine deficiency syndromes following clinical presentation. For proper result interpretation, order urine testing simultaneously.