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HelpTest Code CACR3 Calcium/Creatinine Ratio, Random, Urine
Specimen Required
Supplies: Sarstedt Aliquot Tube 5 mL (T914)
Collection Container/Tube: Clean, plastic urine container with no metal cap or glued insert
Submission Container/Tube: Plastic, 5-mL tube or a clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 4 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Useful For
Evaluation of calcium oxalate and calcium phosphate kidney stone risk
Calculation of urinary supersaturation
Evaluation of bone diseases, including osteoporosis and osteomalacia
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| CCTR | Calcium/Creat Ratio, Random, U | No | Yes |
| CALC5 | Calcium, Random, U | No | Yes |
| CRETR | Creatinine, Random, U | No | Yes |
Method Name
CALC5: Photometric
CRETR: Enzymatic Colorimetric Assay
Reporting Name
Calcium/Creat Ratio, Random, USpecimen Type
UrineSpecimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Refrigerated (preferred) | 14 days | |
| Frozen | 30 days | ||
| Ambient | 72 hours |
Reject Due To
| All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. |
Clinical Information
Calcium is the fifth most common element in the body. It is a fundamental element necessary to form electrical gradients across membranes, an essential cofactor for many enzymes, and the main constituent in bone. Under normal physiologic conditions, the concentration of calcium in serum and in cells is tightly controlled. Calcium is excreted in both urine and feces. Ordinarily about 20% to 25% of dietary calcium is absorbed, and 98% of filtered calcium is reabsorbed in the kidney. Traffic of calcium between the gastrointestinal tract, bone, and kidney is tightly controlled by a complex regulatory system that includes vitamin D and parathyroid hormone. Sufficient bioavailable calcium is essential for bone health. Excessive excretion of calcium in the urine is a common contributor to kidney stone risk.
Reference Values
1 month-<12 months: 0.03-0.81 mg/mg creatinine
12 months-<24 months: 0.03-0.56 mg/mg creatinine
24 months-<3 years: 0.02-0.50 mg/mg creatinine
3 years-<5 years: 0.02-0.41 mg/mg creatinine
5 years-<7 years: 0.01-0.30 mg/mg creatinine
7 years-<10 years: 0.01-0.25 mg/mg creatinine
10 years-<18 years: 0.01-0.24 mg/mg creatinine
18 years-83 years: 0.05-0.27 mg/mg creatinine
Reference values have not been established for patients who are less than 1 month of age.
Reference values have not been established for patients who are greater than 83 years of age.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
82310
82570
Day(s) Performed
Monday through Sunday
Report Available
1 to 3 daysForms
If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.