Uric Acid (on ice-Elitek)

Label Mnemonic:	URICICE
Epic code:	LAB870
Downtime form:	Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Chemistry
6240 RCP
356-3527

Specimen(s):

Plasma

Collection Medium:

Plasma Separator Tube 4.5 mL

Alternate Collection Media:

Call laboratory for additional acceptable specimen collection containers.

Minimum:

3 mL whole blood in PRECHILLED light green top tube or one PRECHILLED Microtainer^® for pediatric patients.

Delivery Instructions:

Keep on ice and deliver to laboratory immediately.

Testing Schedule:

24 hrs/day, 7 days a week, including holidays.

Turn Around Time:

1 hour (upon receipt in laboratory)

Reference Range:

     Age                   Male              Female
0 to <15 days        2.7 – 12.6 mg/dL   2.7 – 12.6 mg/dL
15 days to <1 year   1.5 – 6.2 mg/dL    1.5 – 6.2 mg/dL
1 to <12 years       1.7 – 4.7 mg/dL    1.7 – 4.7 mg/dL
12 to <19 years      2.5 – 7.5 mg/dL    2.5 – 5.7 mg/dL
Adults >= 19 years   3.4 – 7.0 mg/dL    2.4 – 5.7 mg/dL

Pediatric reference intervals updated on 6/15/2021

Colantonio DA, Kyriakopoulou L, Chan MK, Daly CH, Brinc D, Venner AA, Pasic MD, Armbruster D, Adeli K. Closing the gaps in pediatric laboratory reference intervals: a CALIPER database of 40 biochemical markers in a healthy and multiethnic population of children. Clin Chem. 2012 May;58(5):854-68. doi: 10.1373/clinchem.2011.177741. Epub 2012 Feb 27. PMID: 22371482.

Higgins V, Chan MK, Nieuwesteeg M, Hoffman BR, Bromberg IL, Gornall D, Randell E, Adeli K. Transference of CALIPER pediatric reference intervals to biochemical assays on the Roche cobas 6000 and the Roche Modular P. Clin Biochem. 2016 Jan;49(1-2):139-49. doi: 10.1016/j.clinbiochem.2015.08.018. Epub 2015 Aug 19. Erratum in: Clin Biochem. 2016 Oct;49(15):1210. PMID: 26297116.

Comments:

This test is specifically for patients who are taking the drug rasburicase (Elitek). Collection in pre-chilled tubes and rapid transport limits breakdown of uric acid by the uricase enzyme in the blood tube.

Test Limitations:

If directions for specimen collection (pre-chilled tube and 
deliver on ice) are not followed, a false low uric acid will result.

Criterion: Recovery within plus or minus 10% of initial values

Plasma
Icterus: No significant interference up to an I index of 40 
(approximate conjugated and unconjugated bilirubin concentration 40 
mg/dL or 684 umol/l).

Hemolysis: No significant interference up to an H index of 1000 
(approximate hemoglobin concentration: 1000 mg/dL or 621 umol/l).

Lipemia (Intralipid): No significant interference up to an L index of 
1500.

There is poor correlation between turbidity and triglycerides 
concentration.

Ascorbic acid less than 3 mg/dL does not interfere.

Of the drugs tested in vitro, o-methyldopa, desferoxamine and calcium 
dobesilate(e.g. Dexium) cause interference at therapeutic 
concentrations (uric acid level artificially low).

Uricase reacts specifically with uric acid. Other purine derivatives 
can inhibit the uric acid reaction.

Reference:
Glick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences 
in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-474.

Methodology:

Enzymatic Colorimetric

CPT Code:

84550