Urine is the preferred specimen type for the assessment of selenium toxicity and deficiency. For the assessment of recent intake, Selenium, Serum or Plasma is available (0025023).
- Patient Preparation
- Diet, medication, and nutritional supplements may introduce interfering substances. Patients should be encouraged to discontinue nutritional supplements, vitamins, minerals, and non-essential over-the-counter medications (upon the advice of their physician). High concentrations of iodine may interfere with elemental testing. Abstinence from iodine-containing medications or contrast agents for at least 1 month prior to collecting specimens for elemental testing is recommended.
- 24-hour or random urine collection. Specimen must be collected in a plastic container. ARUP studies indicate that refrigeration of urine alone, during and after collection, preserves specimens adequately, if tested within 14 days of collection.
- Specimen Preparation
- Transfer an 8 mL aliquot from a well-mixed collection to ARUP Trace Element-Free Transport Tubes (ARUP supply #43116). Available online through eSupply using ARUP Connect™ or contact ARUP Client Services at (800) 522-2787. (Min: 1 mL)
- Storage/Transport Temperature
- Refrigerated. Also acceptable: Room temperature or frozen.
- Unacceptable Conditions
- Urine collected within 48 hours after administration of a gadolinium (Gd) containing contrast media (may occur with MRI studies). Acid preserved urine. Specimens contaminated with blood or fecal material. Specimens transported in non-trace element free transport tube (with the exception of the original device).
- Record total volume and collection time interval on transport tube and on test request form.
- Ambient: 1 week; Refrigerated: 2 weeks; Frozen: 1 year
|Test Number||Components||Reference Interval|
| ||Selenium, Urine - per volume||0-200 µg/L|
| ||Selenium, Urine - per 24h||0-200 µg/d|
| ||Selenium, Urine - ratio to CRT||No reference interval (µg/g crt)|
| ||Creatinine, Urine - per 24h|
|Component Test Code*||Component Chart Name||LOINC|
|0020207||Creatinine, Urine - per volume||2161-8|
|0020208||Creatinine, Urine - per 24h||2162-6|
|0025066||Selenium, Urine - ratio to CRT||29917-2|
|0025100||Selenium, Urine - per 24h||5727-3|
|0099365||Selenium, Urine - per volume||5726-5|
- Selenium/Creatinine, Random, Urine
- Urine selenium concentration