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Test Code LAB1116 Iodine, Serum

Reporting Name

Iodine, S

Useful For

Determining iodine overload using serum specimens

 

Monitoring iodine levels in individuals taking iodine-containing drugs

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

Serum


Specimen Required


Patient Preparation:

1. Disinfectants (such as Betadine) that contain iodine should not be used during venipuncture.

2. High concentrations of gadolinium and iodine are known to interfere with most metal tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for 96 hours.

Supplies:

-Metal Free B-D Tube (No Additive), 6 mL (T184)

-Metal Free Specimen Vial (T173)

Collection Container/Tube: Plain, royal blue-top Vacutainer plastic trace element blood collection tube

Submission Container/Tube: 7-mL Mayo metal-free, screw-capped, polypropylene vial

Specimen Volume: 1 mL

Collection Instructions:

1. Allow specimen to clot for 30 minutes; then centrifuge the specimen to separate serum from the cellular fraction.

2. Remove the stopper. Carefully pour specimen into Mayo metal-free, polypropylene vial, avoiding transfer of the cellular components of blood. Do not insert a pipet into the serum to accomplish transfer, and do not ream the specimen with a wooden stick to assist with serum transfer.

3. See Trace Metals Analysis Specimen Collection and Transport for complete instructions.


Specimen Minimum Volume

0.3 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 21 days
  Ambient  21 days
  Frozen  21 days

Reference Values

40-92 ng/mL

Day(s) Performed

Tuesday, Friday

Test Classification

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

CPT Code Information

83789

LOINC Code Information

Test ID Test Order Name Order LOINC Value
IOD Iodine, S 2494-3

 

Result ID Test Result Name Result LOINC Value
81574 Iodine, S 2494-3

Clinical Information

Iodine is an essential element required for thyroid hormone production. The measurement of iodine serves as an index of adequate dietary iodine intake and iodine overload, particularly from iodine-containing drugs, such as amiodarone.

Interpretation

Values between 80 ng/mL and 250 ng/mL have been reported to indicate hyperthyroidism.

 

Values above 250 ng/mL may indicate iodine overload.

Cautions

There are no known analytical interferences with this procedure.

 

Administration of iodine-containing contrast media will yield elevated results.

Clinical Reference

1. Allain P, Berre S, Krari N, et al. Use of plasma iodine assay for diagnosing thyroid disorders. J Clin Pathol. 1993;46(5):453-455.

2. Rifai N, Chiu RWK, Young I, Burnham CAD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023

3. Leung AM, Braverman LE, Consequences of excess iodine. Nat Rev Endocrinol. 2014;10(3):136-142. doi: 10.1038/nrendo.2013.251

4. U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry: Toxicological Profile for Iodine. HHS; 2004. Accessed June 29, 2023. Available at www.atsdr.cdc.gov/ToxProfiles/tp158.pdf

Method Description

The metal of interest is analyzed by inductively coupled plasma mass spectrometry.(Unpublished Mayo method)

Report Available

1 to 4 days

Specimen Retention Time

14 days

Reject Due To

Gross hemolysis OK
Gross lipemia OK
Gross icterus OK

NY State Approved

Yes

Method Name

Inductively Coupled Plasma Mass Spectrometry (ICP-MS)