Calcium, 24-Hour Urine without Creatinine

Test Code
CA-UR-SP (4836U)

Quest Code

CPT Codes

CPT code 81050 may be added at an additional charge for volume measurement

Preferred Specimen
10 mL aliquot of a well-mixed, 24-hour urine collection

Minimum Volume

2 mL

Other Acceptable Specimens
Unpreserved urine • Urinalysis transport tube (yellow-top, blue fill line, preservative tube)

Refrigerate during and after collection. Collect urine with 25 mL of 6N HCl to maintain a pH <3. Do not include first morning specimen; collect all subsequent voidings. The last specimen collected should be the first morning specimen voided the following morning at the same time as the previous morning’s first voiding. Specify 24-hour total volume and collection duration on specimen container and test requisition.

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 5 days
Refrigerated: 35 days
Frozen: 6 months

Spectrophotometry (SP)

Setup Schedule

Report Available
1 to 2 days

Oral contraceptive use may depress results.

Reference Range
Unrestricted Calcium Diet
Male 55-300 mg/24 h
Female 35-250 mg/24 h
Restricted Calcium Diet
Male 55-200 mg/24 h
Female 35-200 mg/24 h

Clinical Significance
Urinary calcium reflects dietary intake, rate of calcium absorption by the intestine and bone resorption. Urinary calcium is used primarily to evaluate parathyroid function and the effects of vitamin D. A significant number of patients with primary hyperparathyroidism will have elevated urinary calcium. However, there are other clinical entities that may be associated with increased urine calcium: Sarcoidosis, Paget's disease of bone, vitamin D intoxication, hyperthyroidism and glucocorticoid excess. Decreased urine calcium is seen with thiazide diuretics, vitamin D deficiency and familial hypocalciuric hypercalcemia.

Performing Laboratory
Quest Diagnostics Nichols Institute
27027 Tourney Road
Valencia, CA 91355

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.