Medical Necessity Documentation:
Client Notes:
Patient Preparation:
Specimen Requirements:
10.0 mL Urine Non Sterile Yellow Plastic Containers (No preservatives)
Collection Instructions:
Patient age should be included in order
Freeze immediately
Minimum Volume:
4.0 mL Urine
Transport & Storage: Temperature/Stability:
72 hours Refrigerated
28 days Frozen (transport)
Rejection Criteria:
Ambient | Thawed specimen | Received refrigerated | Samples with pH less than 2
Reference Range:
Refer to Interpretive Results
Critical Ranges:
Test Comments:
Methodology:
Gas Chromatography/Mass Spectrometry (GC/MS)
Clinical Significance:
This test is intended for the diagnosis and monitoring of inherited disorders affecting multiple metabolic pathways.
Organic acidurias are inherited disorders resulting from a deficient enzyme or transport protein. Although most are autosomal recessive disorders, several are X-linked. The more than 60 described organic acidurias affect many metabolic pathways including amino acid metabolism, lipid metabolism, purine and pyrimidine metabolism, the urea cycle, the Krebs cycle and fatty acid oxidation. These disorders are characterized by a wide variety of symptoms such as lethargy, coma, hypotonia, seizures, ataxia, vomiting, failure to thrive, developmental delay, liver disease, neutropenia, thrombocytopenia, osteomalacia and osteoporosis. Severity of presentation is highly variable as is age of onset, and patients may not present with the most characteristic features. Laboratory results commonly indicate metabolic acidosis, increased anion gap, hyperammonemia, hypoglycemia, lactic acidemia, ketosis, or abnormal lipid patterns. Treatment may be based on dietary restrictions and/or supplementation with cofactors (e.g., riboflavin or cobalamin) or conjugating agents (e.g., carnitine or sodium benzoate); however, there is no effective therapy for some of the disorders.
Elevation of one or more organic acids is diagnostic for an organic aciduria; however, elevations should be interpreted in context with clinical findings and/or additional test results. See additional information for a table of selected organic acidurias and associated organic acid elevations. Since many organic acidurias are episodic, the diagnostic efficacy is maximized when the patient is expressing symptoms at the time of specimen collection.
The test will be capable of diagnosing over 30 inherited metabolic defects, and will also allow physicians to determine dietary compliance or the effectiveness of dietary/cofactor therapy for their patients. It can also be used, alone or in conjunction with other tests, to confirm the findings of a positive expanded newborn screen.
Documentation:
Custom Panel:
No
PRODUCTION SCHEDULE
Turn Around Time:
5 to 7 days
Days Performed:
Tuesday, Friday
Sites Performed:
Quest - Chantilly to San Juan Capistrano
PHL Test Code:
ORLQ
EPIC Test Code:
LAB3182
Send Out Test Code:
35820
Alternate Test Names:
Organic Acids Limited, Qnt, UR
Included Tests:
CPT Coding:
82542, 82570