Label Mnemonic: ARSU
Epic Lab Code: LAB361
Downtime Form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Commercial Mail-out Laboratory
5231 RCP
Specimen Instructions:
Refrigerate during 24 hr collection in plastic container.

Commercial laboratory studies indicate that refrigeration of urine alone, during and after collection, preserves specimen as well as any alternative preservatives added before collection, if specimen is tested within 14 days of collection.

Diet, medication, and nutritional supplements may introduce interfering substances. Patients should be encouraged to discontinue nutritional supplements, vitamins, minerals, nonessential over-the-counter medications (upon the advice of their physician), and avoid shellfish and seafood for 48 to 72 hours.

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.
Collection Medium:
Urine - 24 hour/timed plastic urine container
Preferred Minimum: 8 mL urine from a well-mixed, refrigerated, 24 hr urine collection.
Absolute Minimum: 2 mL urine from a well-mixed, refrigerated, 24 hr urine collection.
Rejection Criteria:
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 transport tube (with the exception of the original device).
Turn Around Time:
1-5 days upon receipt at reference laboratory
Reference Range:
Components Reference Interval Arsenic, Urine-per volume 0.0-34.9 μg/L (based on Biological Exposure Index) Arsenic, Urine-per 24 hour 0.0-49.9 μg/d Arsenic, Urine-ratio to CRT 0.0-29.9 μg/gCRT Arsenic, Fractionated, Urine As Organic Refer to report Arsenic Total Inorganic Refer to report Arsenic, Methylated Refer to report Creatinine(24 hour) Male 3-8 years: 140-700 mg/d 9-12 years: 300-1300 mg/d 13-17 years: 500-2300 mg/d 18-50 years: 1000-2500 mg/d 51-80 years: 800-2100 mg/d 81 years and older: 600-2000 mg/d Female 3-8 years: 140-700 mg/d 9-12 years: 300-1300 mg/d 13-17 years: 400-1600 mg/d 18-50 years: 700-1600 mg/d 51-80 years: 500-1400 mg/d 81 years and older: 400-1300 mg/d
Interpretive Data:
The ACGIH Biological Exposure Index (BEI) for arsenic in urine is 35 μg/L. The ACGIH BEI is based on the sum of inorganic and methylated species. For specimens with a total arsenic concentration between 35-2000 μg/L, fractionation is automatically performed to determine the proportions of inorganic, methylated and organic species. It may be appropriate to request fractionation for specimens with a total arsenic greater than 30 μg/gCRT despite a total arsenic concentration less than 35 μg/L. If low-level chronic poisoning is suspected, the μg/gCRT ratio may be a more sensitive indicator of arsenic exposure than the total arsenic concentration.
To differentiate between organic and the more toxic inorganic forms, an arsenic speciation test is recommended and can be performed with the existing specimen by contacting the clinical laboratory lead scientist at pager 131-7283.

If urine, arsenic is abnormal, additional testing is performed by the reference laboratory. The patient will be charged for this testing when applicable.
Quantitative High Performance Liquid Chromatography/Quantitative Inductively Coupled Plasma-Mass Spectrometry
CPT Code:
82175; if reflexed, add 82175