Epic Test Code LAB21067 Iodine, 24 Hour, Urine
Additional Codes
MML Code: UIOD
LIS Code: IODU
NY State Approved
YesPerforming Laboratory
Mayo Clinic Laboratories in RochesterReporting Name
Iodine, 24 Hr, UMethod Name
Inductively Coupled Plasma Mass Spectrometry (ICP-MS)
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 146 days | |
Ambient | 146 days | ||
Frozen | 146 days |
Necessary Information
24-Hour volume (in milliliters) is required.
Specimen Required
Patient Preparation:
1. High concentrations of gadolinium and iodine are known to interfere with most metal tests. If gadolinium- or iodine-containing contrast media has been administered, wait a minimum of 96 hours before starting collection.
2. If this test is used in conjunction with the (131)I uptake test, then specimen collection should begin immediately after the dose of (131)I is given (ie, the patient should void and discard urine just prior to the (131)I dose, and all subsequent urine should be collected for the next 24 hours). The last void should be included in the collection.
Supplies: Urine Tubes, 10 mL (T068)
Container/Tube: Plastic: 10-mL urine tube or clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 10 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. Refrigerate specimen within 4 hours of completion of 24-hour collection.
3. See Trace Metals Analysis Specimen Collection and Transport for complete instructions.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Specimen Type
UrineSpecimen Minimum Volume
0.3 mL
Reference Values
0-17 years: Not established
≥18 years: 75-851 mcg/24 hour
Report Available
1 to 4 daysDay(s) Performed
Tuesday, Friday
CPT Code Information
83789
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Useful For
Assessing iodine toxicity or recent exposure in a 24-hour urine collection
Monitoring iodine excretion rate as index of replacement therapy
Special Instructions
Clinical Information
Iodine is an essential element for thyroid hormone production. The measurement of urinary iodine is preferred for assessment of toxicity, recent exposure, and monitoring iodine excretion rate as an index of replacement therapy.
Interpretation
Measurement of urinary iodine excretion provides the best index of dietary iodine intake and deficiency is generally indicated when the concentrations are below 100 mcg/L.
World Healthcare Organization (WHO) Criteria for Assessing Iodine Status
Children older than 6 years old and adults
Median urinary iodine (mcg/L) |
Iodine intake |
Iodine status |
<20 |
Insufficient |
Severe deficiency |
20-49 |
Insufficient |
Moderate deficiency |
50-99 |
Insufficient |
Mild deficiency |
100-199 |
Adequate |
Adequate nutrition |
200-299 |
Above requirements |
May pose a slight risk of more than adequate |
>299 |
Excessive |
Risk of adverse health consequences |
Pregnant women
Median urinary iodine (mcg/L) |
Iodine intake |
<150 |
Insufficient |
150-249 |
Adequate |
250-499 |
Above requirements |
>499 |
Excessive |
Lactating women and children younger than 2 years old
Median urinary iodine (mcg/L) |
Iodine intake |
<100 |
Insufficient |
>99 |
Adequate |
Cautions
Administration of iodine-based contrast media and drugs containing iodine, such as amiodarone, will yield elevated results.