| Ordering Code | 248 |
|---|---|
| Test Name | Calcium, 24 Hr Urine |
| Alias | 24 Hr Urine Calcium 24 Hr Urine Ca++ |
| Preferred Specimen | Urine, 24 Hour |
| Preferred Container | 24 Hour Urine Container |
| Optimum Volume | 1.0 mL |
| Collection Instructions | Keep refrigerated during collection. Do not include first morning specimen; collect all subsequent voidings. The last sample collected should be the first morning specimen voided the following morning at the same time as the previous morning first voiding Record entire 24 Hr Volume on container and requisition No preservatives added. |
| Handling Instructions | Send a well-mixed, 50 mL aliquot of specimen Processing: Prior to analysis, acidify the urine specimen to a pH <2 with 6 N HCL. Follow laboratory specific procedures for urine acidification to ensure an appropriate volume of acid is used and to avoid spurious values resulting from dilution of the sample by the acid. Samples with urine pH below 1.5 may result in negative bias. |
| Transport Requirements | Oahu: Ambient Airline: Ambient |
| Specimen Stability | Ambient: 5 Days Refrigerated: 5 Weeks Frozen: 6 Months |
| Rejection Criteria | Specimen older than stability limits |
| Avail. Stat | NO |
| Analytic Time | 1 Day |
| Methodology | Arsenazo III |
Reference range(s)
The reference ranges listed below are valid on this date of September 18, 2025.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| Total Volume | ALL | mL | See report. | ||||||
| Total Time | ALL | minutes | See report. | ||||||
| 24-Hr Urine Calcium | ALL | 100-300 | 100-300 | mg/24hr | |||||
| Calcium, Urine | ALL | mg/dL | See report. |
