Ordering Recommendation

Recommended for the assessment of iodine nutritional status. This test reports total iodine from all iodine-containing species present in the specimen but does not determine the chemical form (species) of the iodine present. For determination of iodine excess and monitoring iodine overload in patients administered iodine-containing medications, refer to Iodine, Serum (2007463).

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Diet, medication, and nutritional supplements may introduce interfering substances. Patients should be encouraged to discontinue nutritional supplements, vitamins, minerals, nonessential over-the-counter medications for 48 hours (upon the advice of their physician). In addition, the administration of iodine-based contrast media and drugs containing Iodine may yield elevated results. Specimen must be collected in a plastic container and should be refrigerated after collection.

Collect

24-hour or random urine collection.

Specimen Preparation

Transfer an 8 mL aliquot from a well-mixed collection to ARUP Trace Element-Free 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.

Unacceptable Conditions

Acid preserved urine. Specimens collected within 72 hours after administration of iodinated or gadolinium-based contrast media. Specimens contaminated with blood or fecal material. Specimens transported in non-trace element-free transport tube (with the exception of the original device).

Remarks

Record the total volume and collection time interval on transport tube and on test request form.

Stability

Ambient: 2 months; Refrigerated: 2 months; Frozen: 2 months

Methodology

Quantitative Inductively Coupled Plasma-Mass Spectrometry

Performed

Tue, Thu, Sat

Reported

1-5 days

Reference Interval

Test Number
Components
Reference Interval
  Creatinine, Urine - per 24h
Age
Male (mg/d)
Female (mg/d)
3-8 years 140-700 140-700
9-12 years 300-1300 300-1300
13-17 years 500-2300 400-1600
18-50 years 1000-2500 700-1600
51-80 years 800-2100 500-1400
81 years and older 600-2000 400-1300

  Iodine, Urine - per volume 16 years and older: 26.0-705.0 µg/L
  Iodine, Urine - per 24h 16 years and older: 93.0-1125.0 µg/d
  Iodine, per gram of CRT 35.0-540.0 µg/g CRT

Interpretive Data

Values greater than 1000 µg/L may indicate dietary excess, but more frequently suggest recent drug or contrast media exposure.

Per 24h calculations are provided to aid interpretation for collections with a duration of 24 hours and an average daily urine volume. For specimens with notable deviations in collection time or volume, ratios of analytes to a corresponding urine creatinine concentration may assist in result interpretation.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)

Note

Hotline History

N/A

CPT Codes

83018

Components

Component Test Code* Component Chart Name LOINC
0020207 Creatinine, Urine - per volume 2161-8
0020208 Creatinine, Urine - per 24h 2162-6
0097110 Total Volume 19153-6
0097111 Hours Collected 30211-7
2007466 Iodine, Urine - per volume 26842-5
2007467 Iodine, Urine - per 24h 2492-7
2007468 Iodine, per gram of CRT 55928-6
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • I urine
  • Iodide urine
  • Urinary Free Iodine
  • Urinary Iodine
Iodine, Urine