Test Code CDUCR Cadmium/Creatinine Ratio, Random, Urine
Specimen Required
Patient Preparation: 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: Urine Tubes, 10 mL (T068)
Collection Container/Tube: Clean, plastic urine container with no metal cap or glued insert
Submission Container/Tube: Plastic, 10-mL urine tube or clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 3 mL
Collection Instructions:
1. Collect urine a random urine specimen.
2. See Metals Analysis Specimen Collection and Transport for complete instructions.
Secondary ID
608906Useful For
Detecting exposure to cadmium, a toxic heavy metal, using random urine specimens
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| CDCU | Cadmium/Creatinine Ratio, U | No | Yes |
| CRETR | Creatinine, Random, U | No | Yes |
Special Instructions
Method Name
CDCU: Triple-Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS/MS)
CRETR: Enzymatic Colorimetric Assay
Reporting Name
Cadmium/Creat Ratio, Random,USpecimen Type
UrineSpecimen Minimum Volume
1.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 28 days |
| Frozen | 28 days | |
| Ambient | 14 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
Cadmium toxicity resembles that of the other heavy metals, including arsenic, mercury, and lead. The kidney is the primary organ affected Kidney dysfunction with proteinuria and slow onset (over a period of years) is the typical presentation. Measurable changes in proximal tubule function, such as decreased clearance of para-aminohippuric acid, also develop over several years and precede overt kidney failure.
Inhalation of cadmium vapor can cause nasal epithelial deterioration and pulmonary congestion resembling chronic emphysema.
For nonsmokers, food is the primary source of cadmium exposure. In general, leafy vegetables such as lettuce and spinach, potatoes, grains, peanuts, soybeans, and sunflower seeds contain high levels of cadmium. For smokers, tobacco smoke is the most common source of exposure is and has been implicated as the primary source of cadmium associated with reproductive toxicity in both men and women.
Chronic cadmium exposure can cause cumulative kidney damage. Cadmium excretion is proportional to creatinine unless kidney damage is present. Cadmium-induced kidney damage may be detected by increased cadmium excretion relative to creatinine.
For Occupational Safety and Health Administration-mandated workplace exposure monitoring (Fed Reg 57:42,102-142,463, September 1992), measure urine cadmium and creatinine and report results as mcg of cadmium per gram of creatinine.
Reference Values
CADMIUM/CREATININE:
0-17 years: Not established
≥18 years: <0.6 mcg/g creatinine
CREATININE:
≥18 years: 16-326 mg/dL
Reference values have not been established for patients who are younger than 18 years.
Interpretation
Urine cadmium levels primarily reflect total body burden of cadmium. Cadmium excretion above 3.0 mcg/g creatinine indicates significant exposure to cadmium.
For occupational testing, the Occupational Safety and Health Administration cadmium standard is less than 3.0 mcg/g creatinine, and the biological exposure index is 5 mcg/g creatinine.
Method Description
Cadmium:
The metal of interest is analyzed by triple-quadrupole inductively coupled plasma mass spectrometry. (Unpublished Mayo method)
Creatinine:
This enzymatic method is based on the conversion of creatinine with the aid of creatininase, creatinase, and sarcosine oxidase to form glycine, formaldehyde, and hydrogen peroxide. Catalyzed by peroxidase the liberated hydrogen peroxide reacts with 4-aminophenazone and HTIB (2,4,6-triiodo03-hydroxybenzoic acid) to form a quinone imine chromogen. The color intensity of the quinone imine chromogen formed is directly proportional to the creatinine concentration in the reaction mixture.(Package insert: Creatinine plus ver.2. Roche Diagnostics; 07/2024)
Performing Laboratory
Mayo Clinic Laboratories in Rochester
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
82300
82570
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| CDUCR | Cadmium/Creat Ratio, Random,U | 13471-8 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 608902 | Cadmium/Creatinine Ratio, U | 13471-8 |
| CRETR | Creatinine, Random, U | 2161-8 |
Day(s) Performed
Monday through Friday