Orotic Acid, Quantitative, Urine

Create a PDF of this page
EGL Genetics will be discontinuing this assay as of 07/01/2017. For any questions or concerns, please contact Customer Service at (470) 378-2200 or a laboratory genetic counselor at eglgc@egl-eurofins.com.

Condition Description

Infants with urea cycle disorders often initially appear normal, but rapidly develop cerebral edema and related signs of:
  • lethargy
  • anorexia
  • hyperventilation/hypoventilation
  • hypothermia
  • seizures
  • neurologic posturing
  • coma
In milder or partial urea cycle enzyme deficiencies, ammonia accumulation may be triggered by illness or stress at almost any time of life, resulting in multiple mild elevations of plasma ammonia concentration. Hyperammonemia is less severe and symptoms are more subtle. In patients with partial enzyme deficiencies, the first recognized clinical episode may be delayed for months or years.


This test should be used in conjunction with a plasma amino acids analysis to detect urea cycle defects (particularly ornithine transcarbamylase (OTC) deficiency) in patients with elevated blood ammonia. The test will also detect hereditary orotic aciduria due to defective (pyrimidine) metabolism.


Spectrophotometric Assay.

Detection and Reference Range

Test results can be influenced by the age and eating status of the patient. This assay is typically used supplementary to a second test, such as an amino acids analysis or acylcarnitine profile, to confirm a diagnosis.
Reference Range
Click here for reference range.

Specimen Requirements

Additional Specimen Collection/Handling Instructions Required for this Test
For diagnostic purposes, specimens should ideally be collected during time of acute illness as abnormal metabolite levels may decrease, sometimes to near normal concentrations, when patient is well.

Type: Urine

Specimen Requirements:

In a clean container without preservatives: 5-10 ml. Freeze.

Fasting or first void sample is preferable.

Specimen Collection and Shipping: Ship frozen sample on dry ice with overnight delivery.

Special Instructions

Please indicate any medications or dietary changes on the test requisition form.
Amino Acids Analysis (AA) - Urine & Plasma are used in the diagnosis and evaluation of patients with metabolic conditions.

How to Order