Calcium, Ionized
Test Code
Clinical Significance
Calcium, Ionized - Ionized calcium represents the true "bioavailable" calcium in the circulation. In situations where the total calcium is normal but does not fit the clinical picture, e.g. , hyperparathyroidism, a determination of the ionized calcium will, many times, show an elevation in the "bioavailable" calcium component. This may be due to alterations in protein concentrations, especially albumin, that binds most of the calcium in the circulation.
Test Resources
Test Details
Methodology
Reference Range(s)
| <8 Months | 5.3-6.3 mg/dL |
| 8-11 Months | 5.2-6.1 mg/dL |
| 1 Year | 5.1-6.0 mg/dL |
| 2 Years | 4.9-5.8 mg/dL |
| 3 Years | 4.9-5.7 mg/dL |
| 4-6 Years | 4.8-5.7 mg/dL |
| 7-12 Years | 4.8-5.6 mg/dL |
| 13-17 Years | 4.8-5.5 mg/dL |
| 18-89 Years | 4.7-5.5 mg/dL |
| ≥90 Years | 4.5-5.5 mg/dL |
Alternative Name(s)
Preferred Specimen(s)
2 mL serum collected in a gel barrier tube
Alternative Specimen(s)
SST (red/black-top) tube
Minimum Volume
0.6 mL
Collection Instructions
Let clot and spin immediately with the cap on. Do not open tube. Ship the unopened gel barrier tube at room temperature.
If submitting with any other assay, please submit a separate tube for this test.
Transport Container
Unopened gel barrier tube
Transport Temperature
Room temperature
Specimen Stability
- Room temperature: 7 days
- Refrigerated: 7 days
- Frozen: Unacceptable
Reject Criteria
Gross hemolysis • Grossly lipemic • Received frozen • Red-top tube (no gel)
Setup Schedule
Let clot and spin immediately with the cap on. Do not open tube. Ship the unopened gel barrier tube at room temperature.
If submitting with any other assay, please submit a separate tube for this test.
Refrigerated: 7 days
Frozen: Unacceptable