Magnesium, Red Blood Cells
Also known as: MG RBC
Use
This test, measuring the magnesium concentration in red blood cells (RBCs), is useful for assessing tissue stores of magnesium. RBC magnesium results reflect the intracellular stores and general homeostasis of magnesium. This test is particularly utilized when there is a need to determine intracellular magnesium levels, which can provide insights into magnesium deficiency and help guide treatment decisions.
Special Instructions
For routine assessment of magnesium deficiency, it is recommended to use Plasma or Serum Magnesium testing. It is important to ensure that RBCs are separated from plasma promptly after collection to avoid false low results due to lysed RBCs.
Limitations
The test may provide falsely low results if the RBCs in the submitted specimen are lysed or if they are not promptly separated from plasma. Additionally, specimens collected in tubes other than royal blue (K2EDTA) or royal blue (NaHep) are not acceptable for testing. Clotted or grossly hemolyzed specimens may also lead to inaccurate results.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 26746-8
Result Turnaround Time
1-4 days
Related Documents
For more information, please review the documents below
Specimen
Other
Volume
Not provided
Minimum Volume
0.6 mL
Container
Royal blue (K2EDTA) or Royal blue (NaHep) tube or trace element-free transport tube
Collection Instructions
Centrifuge whole blood and separate RBCs from plasma within 2 hours of collection. Submit packed RBCs in original tube OR transfer 2 mL RBCs to an ARUP Trace Element-Free Transport Tube.
Patient Preparation
None specified.
Storage Instructions
Room temperature storage is preferred. Refrigeration is also acceptable.
Causes for Rejection
Specimens collected in tubes other than royal blue (K2EDTA) or royal blue (NaHep) tube or trace element-free transport tube. Clotted or grossly hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 2 weeks |
| Refrigerated | 2 weeks |
| Frozen | Unacceptable |