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HelpTest 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 | Special Container |
|---|---|---|---|
| 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
The toxicity of cadmium resembles the other heavy metals (arsenic, mercury, and lead) in that it attacks the kidney; kidney dysfunction with proteinuria with 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 occur over a period of years and precede overt kidney failure.
Breathing the fumes of cadmium vapors leads to nasal epithelial deterioration and pulmonary congestion resembling chronic emphysema.
For nonsmokers, the primary source of cadmium exposure is from the food supply. In general, leafy vegetables such as lettuce and spinach, potatoes and grains, peanuts, soybeans, and sunflower seeds contain high levels of cadmium. For smokers, the most common source of cadmium exposure is tobacco smoke, which has been implicated as the primary source of the metal leading to reproductive toxicity in both male and female patients.
Chronic exposure to cadmium causes accumulated kidney damage. The excretion of cadmium is proportional to creatinine except when kidney damage has occurred. Kidney damage due to cadmium exposure can be detected by increased cadmium excretion relative to creatinine.
Occupational Safety and Health Administration mandated (Fed Reg 57:42,102-142,463, September 1992) that all monitoring of employees exposed to cadmium in the workplace should be done using the measurement of urine cadmium and creatinine, expressing the results of 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 of age.
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.
Cautions
Collection of urine specimens through a catheter frequently results in elevated values because rubber contains trace amounts of cadmium that are extracted as urine passes through the catheter.
Clinical Reference
1. deBurbure C, Buchet J-P, Leroyer A, et al. Renal and neurologic effects of cadmium, lead, mercury, and arsenic in children: Evidence of early effects and multiple interactions at environmental exposure levels. Environ Health Perspect. 2006;114(4):584-590
2. Schulz C, Angerer J, Ewers U, et al. Revised and new reference values for environmental pollutants in urine or blood of children in Germany derived from the German Environmental Survey on Children 2003-2006(GerESIV) Int J Hyg Environ Health. 2009;212(6):637-647
3. Occupational Safety and Health Administration: Cadmium exposure and control. US Department of Labor; Updated 9/2/2008. Accessed July 17, 2020. Available at osha.gov/SLTC/cadmium/evaluation.html
4. Agency for Toxic Substances and Disease Registry: Toxicological profile for cadmium. US Department of Health and Human Services; September 2012. Available at www.atsdr.cdc.gov/ToxProfiles/tp5.pdf
5. Strathmann FG, Blum LM. Toxic elements. In: Rifai N, Chiu RWK, Young I, Burnham CD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:chap 44
6. Wang M, Chen Z, Song W, Hong D, Huang L, Li Y. A review on cadmium exposure in the population and intervention strategies against cadmium toxicity. Bull Environ Contam Toxicol. 2021;106(1):65-74. doi:10.1007/s00128-020-03088-1
Method Description
Cadmium:
The metal of interest is analyzed by triple-quadrupole inductively coupled plasma mass spectrometry. (Unpublished Mayo method)
Creatinine:
The enzymatic method is based on the determination of sarcosine from creatinine with the aid of creatininase, creatinase, and sarcosine oxidase. The liberated hydrogen peroxide is measured via a modified Trinder reaction using a colorimetric indicator. Optimization of the buffer system and the colorimetric indicator enables the creatinine concentration to be quantified both precisely and specifically.(Package insert: Creatinine plus ver 2. Roche Diagnostics; V15.0, 03/2019)
Specimen Retention Time
14 daysPerforming 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