Sign in →

Test ID HYOX Hyperoxaluria Panel, Urine

Reporting Name

Hyperoxaluria Panel, U

Useful For

Distinguishing between primary and secondary hyperoxaluria

 

Distinguishing between primary hyperoxaluria types 1, 2, and 3

Specimen Type

Urine


Specimen Required


Patient Preparation: Fasting-overnight (12-14 hours).

Supplies: Urine Tubes, 10 mL (T068)

Container/Tube: Plastic, 10-mL urine tube (T068)

Specimen Volume: 10 mL

Collection Instructions:

1. Have patient void the first-morning specimen, then collect specimen within 2 hours of first-morning void while patient continues to fast. Fluids are allowed.

2. No preservative.

3. Immediately freeze specimen.


Specimen Minimum Volume

1.1 mL

Specimen Stability Information

Specimen Type Temperature Time
Urine Frozen (preferred) 90 days
  Refrigerated  14 days

Reference Values

REPORTING/INTERPRETING RESULTS

Reference Intervals (Normal Ranges):

 

Glycolate

≤17 years: ≤75 mg/g creatinine

≥18 years: ≤50 mg/g creatinine

 

Glycerate

≤31 days: ≤75 mg/g creatinine

32 days - 4 years: ≤125 mg/g creatinine

5 - 10 years: ≤55 mg/g creatinine

≥11 years: ≤25 mg/g creatinine

 

Oxalate

≤6 months: ≤400 mg/g creatinine

7 months - 1 year: ≤300 mg/g creatinine

2 - 6 years: ≤150 mg/g creatinine

7 - 10 years: ≤100 mg/g creatinine

≥11 years: ≤75 mg/g creatinine

 

4-hydroxy-2-oxoglutarate (HOG)

10 mg/g creatinine

Day(s) and Time(s) Performed

Thursdays; 8 a.m.

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

82542

LOINC Code Information

Test ID Test Order Name Order LOINC Value
HYOX Hyperoxaluria Panel, U 53710-0

 

Result ID Test Result Name Result LOINC Value
50592 Glycolate 13751-3
50593 Glycerate 13749-7
50594 Oxalate 13483-3
38049 4-hydroxy-2-oxoglutarate In Process
29982 Interpretation 59462-2
29984 Reviewed By No LOINC Needed

Testing Algorithm

See Hyperoxaluria Diagnostic Algorithm in Special Instructions.

Clinical Information

Increased urinary oxalate frequently leads to renal stone formation and renal insufficiency. Identifying the cause of hyperoxaluria has important implications in therapy, management and prognosis.

 

Hyperoxalurias are classified as primary and secondary. Primary hyperoxaluria is an inherited disorder of oxalate metabolism while secondary hyperoxaluria is an acquired condition resulting from either increased intake of dietary oxalate or altered intestinal oxalate absorption. Primary hyperoxalurias are classified into types 1, 2, and 3.

 

Type 1 (PH1), an autosomal recessive deficiency of peroxisomal alanine: glyoxylate aminotransferase due to mutations in the AGXT gene, is characterized by increased urinary oxalic, glyoxylic, and glycolic acids. PH1 is the most common with manifestations that include deposition of calcium oxalate in the kidneys (nephrolithiasis, nephrocalcinosis), and end-stage renal disease. Calcium oxalate deposits can be further deposited in other tissues such as the heart and eyes, and lead to a variety of additional symptoms. Age of onset is variable with a small percentage of patients presenting in the first year of life with failure to thrive, nephrocalcinosis, and metabolic acidosis. Approximately half of affected individuals show manifestations of PH1 in late childhood or early adolescence, and the remainder present in adulthood with recurrent renal stones. Some individuals with PH1 respond to supplementary pyridoxine therapy.

 

Hyperoxaluria type 2 (PH 2) is due to a defect in GRHPR gene resulting in a deficiency of the enzyme hydroxypyruvate reductase. PH2 is autosomal recessive and identified by an increase in urinary oxalic and glyceric acids. Like PH1, PH2 is characterized by deposition of calcium oxalate in the kidneys (nephrolithiasis, nephrocalcinosis), and end-stage renal disease. Most individuals have symptoms of PH2 during childhood, and it is thought that PH2 is less common than PH1.

 

Hyperoxaluria type 3 (PH3), due to recessive mutations in HOGA1 (formerly DHDPSL), occurs in a small percentage of individuals with primary hyperoxaluria. HOGA1 encodes a mitochondrial 4-hydroxy-2-oxoglutarate aldolase that catalyzes the 4th step in the hydroxyproline pathway. PH3 is characterized biochemically by increased urinary excretion of oxalate and 4-hydroxy-2-oxoglutarate (HOG). As with PH types 1 and 2, PH type 3 is characterized by calcium-oxalate deposition in the kidneys and/or kidney stone formation. Most individuals with PH3 have early onset disease with recurrent kidney stones and urinary tract infections as common symptoms. End-stage renal disease is not a characteristic of PH3. Of note, individuals with heterozygous mutations in HOGA1 can have variable and intermittent elevations of urine oxalate.

 

Secondary hyperoxalurias are due to hyperabsorption of oxalate (enteric hyperoxaluria); total parenteral nutrition in premature infants; ingestion of oxalate, ascorbic acid, or ethylene glycol; or pyridoxine deficiency, and may respond to appropriate therapy.

 

A diagnostic workup in an individual with hyperoxaluria demonstrates increased concentration of oxalate in urinary metabolite screening. If glycolate, glycerate, or HOG is present, a primary hyperoxaluria is indicated. Additional analyses can include molecular testing for PH1 (AGXTG / Alanine:Glyoxylate Aminotransferase (AGXT) Mutation Analysis (G170R), Blood or AGXTZ / AGXT Gene, Full Gene Analysis), PH2 (GRHPZ / GRHPR Gene, Full Gene Analysis), or PH3 (HOGA1 testing not available at Mayo at  this time).

Interpretation

Increased concentrations of oxalate and glycolate indicate type 1 hyperoxaluria.

 

Increased concentrations of oxalate and glycerate indicate type 2 hyperoxaluria.

 

Increased concentrations of oxalate and 4-hydroxy-2-oxoglutarate indicate type 3 hyperoxaluria.

 

Increased concentrations of oxalate with normal concentrations of glycolate, glycerate, and 4-hydroxy-2-oxoglutarate indicate secondary hyperoxaluria.

Clinical Reference

1. Bhasin B, Urekli HM, Atta MG: Primary and secondary hyperoxaluria: Understanding the enigma. World J Nephrol 2015;4(2):235-244 doi: 10.5527/wjn.v4.i2.235

2. Danpure CJ: Primary Hyperoxaluria. In The Online Metabolic and Molecular Bases of Inherited Disease. Edited by D Valle, AL Beaudet, B Vogelstein, et al. New York. McGraw-Hill, 2014. Accessed August 26 2015. Available at: http://ommbid.mhmedical.com/content.aspx?bookid=971&Sectionid=62641527

3. Byrd DJ, Latta K: Hyperoxaluria. In Physician's Guide to the Laboratory Diagnosis of Metabolic Disease. Edited by N Blau, ED Chapman. Hall Medical, 1996, pp 377-390

4. Fraser AD: Importance of glycolic acid analysis in ethylene glycol poisoning. Clin Chem 1998;44(8):1769

5. Beck BB, Baasner A, Buescher A, et al: Novel findings in patients with primary hyperoxaluria type III and implications for advanced molecular testing strategies. Eur J Hum Genet 2013;21:162-172

Analytic Time

14 days

Method Name

Gas Chromatography-Mass Spectrometry (GC-MS)

Forms

New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (T576) is available in Special Instructions.