Test Code LAB6754 Orotic Acid, Urine
Performing Section
Biochemical Genetics
Purpose/Principle
Excretion of orotic acid in urine is increased in several inherited disorders of the urea cycle and in the HHH syndrome (hyperammonemia, homocitrullinuria, and hyperornithinemia). This method measures the amount of orotic acid present using stable isotope dilution methodology.
Special Collection Notes
Random Urine, morning specimen preferred.
No preservatives
Specimen Type
Urine:
Sterile Container
Specimen Volume
Preferred: 4.0 mL
Minimum: 1.5 mL
Processing Instructions
Store and ship sample frozen on dry ice.
Temperature
Frozen (dry ice)
Test Components
Orotic Acid, Urine
Reference Range
0.0-4.6 mcg/mg UCr
TAT
7 days
Sample Stability
Refrigerated: 24 hours
Frozen @-20 Celsius: 30 days
Frozen @ -80 Celsius: Indefinitely
Aliases
Argininosuccinic aciduria
Cit I
Citrullinemia I
Hereditary orotic aciduria
HHH
Hyperornithinemia, hyperammonemia, LPI
Lysinuric protein intolerance
Ornithine transcarbamylase deficiency
Uridine monophosphate synthesis (UMPS)
CPT
82542
Test/Batch Schedule
Run once a week (day varies)