Feb 1, 2018




Clinical Hub,Tools & Resources,UWHC Lab Test Directory,Chemistry

Calcium, Urine, 24 hour

Calcium, Urine, 24 hour (UCA) Chemistry Lab Test

Name: Calcium, Urine, 24 hour

Test Name: Calcium, Urine, 24 hour

Health Link Test Code: UCA

LIS Test Code: UCA

CPT Code(s): 82340

Methodology: Arsenazo III

Days Performed: Daily, 24 hours.

In-Lab Turnaround Time: 4 hours.

Stat In-Lab Turnaround Time: 2 hours.

Specimen: 24 hour timed urine

Collection Container: 24 hour urine container

Collection Instructions:

Timed urine collection accepted. No preservative necessary. For timed urine collections, collect all urine in container provided. Add "Refrigerate" sticker to 24-hour container.


For 24-hour urine test the collection period must be within 22-26 hours. Collection period starts after first void of the period. It is very important to refrigerate specimen during and after the collection. Indicate the date and time collection started and date and time collection finished. If questions about collection process or container does not have instructions attached, call (608) 263-7060 for assistance.


Patient instructions available at www.uwhealth.org. Search for 24-hour urine collection or HF#4339.

Collection Volume: Entire collection

Stability Ambient:

2 days

Stability Refridgerated:

4 days

Stability Frozen:

3 weeks

Sample Analyzed: Urine aliquot

Testing Volume: 0.5 mL

Pediatric Testing Volume: 0.2 mL

Outreach Specimen Processing:

Mix urine well and note volume and period. Acidify with 6 N HCl to a pH of 2-3. A pH lower than 2 may cause assay interference. Mix well and let stand for one hour. Recheck pH. Transport 50 mL acidified aliquot with coolant pack to the laboratory along with volume and period information.

Specimen Transport:

Transport specimen to the laboratory. Transport with coolant pack if coming from clinic location.


 0-17 years  up to 6.0 mg/kg/24 hours
 18 years and up  100-300 mg/24 hours

Interpretation Type: Reference Interval

Additional Information:

Results for excretion are calculated only for collections of 22-26 hours.

The urine calcium result is increased by a maximum of 0.1 mg/dL for each 1.0 mg/dL of magnesium in the urine specimen.