|
|
| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Orotic Acid, Urine with Creatinine
Test Code38684
CPT Codes
83921, 82570
Preferred Specimen
10 mL urine with no preservative collected in a sterile, screw-cap container
Minimum Volume
0.6 mL
Instructions
The following information should be provided with the specimen: Date of collection, age of the patient. Urine samples should not have any preservatives added. Freeze as soon as possible after collection. Ship frozen. Do not thaw.
Transport Temperature
Frozen
Specimen Stability
Room temperature: Unacceptable
Refrigerated: 7 days
Frozen: 28 days
Refrigerated: 7 days
Frozen: 28 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Shipped refrigerated (2-8°C) • Samples with pH less than 2 • Fecal contamination
Methodology
Chromatography/Mass Spectrometry
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Wednesday, Sunday Morning
Report available: 6 Days
Report available: 6 Days
Reference Range
Orotic Acid
Creatinine, Random Urine
| <2 weeks | 0.7-4.5 mmol/mol crt |
| 2 weeks-1 year | 1.0-6.5 mmol/mol crt |
| 2-10 years | 0.2-3.4 mmol/mol crt |
| 11-17 years | 0.2-2.0 mmol/mol crt |
| ≥18 years | 0.2-2.8 mmol/mol crt |
Creatinine, Random Urine
| 0-6 months | 0.18-2.48 mmol/L |
| 7-11 months | 0.18-2.74 mmol/L |
| 1-2 years | 0.18-9.72 mmol/L |
| 3-8 years | 0.18-11.49 mmol/L |
| 9-12 years | 0.18-14.14 mmol/L |
| >12 years | 1.77-23.31 mmol/L |
Clinical Significance
Orotic acid is an intermediate metabolite in the de novo pathway of pyrimidine nucleotide synthesis. When present at high levels in the blood, orotic acid accumulates in the liver, enters into the plasma, and is excreted by the kidney. There are several inherited metabolic disorders in which levels of orotic acid are increased. Certain medications can increase orotic acid levels as well.
Measurement of orotic acid levels in urine is useful in evaluating the causes of hyperammonemia. Urea cycle disorders are a common cause of inherited hyperammonemia; orotic acid is elevated in ornithine transcarbamylase (OTC) deficiency, citrullinemia, and argininosuccinic aciduria. Orotic acid is also elevated in hereditary orotic aciduria and in defects of the dibasic amino acid transporter.
Measurement of orotic acid levels in urine is useful in evaluating the causes of hyperammonemia. Urea cycle disorders are a common cause of inherited hyperammonemia; orotic acid is elevated in ornithine transcarbamylase (OTC) deficiency, citrullinemia, and argininosuccinic aciduria. Orotic acid is also elevated in hereditary orotic aciduria and in defects of the dibasic amino acid transporter.
