Carbohydrate, Urine
Use
Screening for conditions associated with increased excretion of carbohydrates, including inborn errors of fructose and galactose metabolism. The identification and quantitation of carbohydrates, particularly galactose and fructose, is useful to screen for inborn errors of metabolism such as galactosemia and hereditary fructose intolerance. The presence of carbohydrates in urine can also indicate specific pathological conditions or dietary consumption. This test is useful as an initial screen and abnormal results require further confirmation by enzyme assays, molecular genetic analysis, or correlation with other laboratory testing.
Special Instructions
This test is not recommended as a follow up for abnormal newborn screening for galactosemia. For those cases, order the GCT / Galactosemia Reflex, Blood and consider additional tests such as GAL1P / Galactose-1-Phosphate, Erythrocytes, and GATOL / Galactitol, Quantitative, Urine. Patient's age is required.
Limitations
The ingestion of sorbose will interfere with fructose quantitation and this will be noted in the report. In infants and pediatric patients, higher normal carbohydrate excretion can lead to false positives for reducing substances in urine. In some cases, normal carbohydrate levels in urine may not rule out pathological conditions, necessitating further biochemical testing.
New York Approved
Methodology
Mass Spectrometry (GC-MS)
Biomarkers
LOINC Codes
- 74447-4
- 5809-9
- 75051-3
- 34309-5
- 25102-5
- 34312-9
- 76132-0
- 74438-3
- 74895-4
- 48147-3
- 18771-6
- 59462-2
Result Turnaround Time
3-9 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
5 mL
Minimum Volume
1 mL
Container
Plastic, 10-mL urine tube
Collection Instructions
Collect an early-morning (preferred) random urine specimen. No preservative.
Causes for Rejection
Urine containing preservatives
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 42 days |