Test Code MG Magnesium
Additional Codes
| EPIC | LAB4140 |
Clinical Significance
This assay is used for diagnosing and monitoring hypomagnesemia (magnesium deficiency) and hypermagnesemia (magnesium excess). Numerous studies have shown a correlation between magnesium deficiency and changes in calcium‑, potassium‑ and phosphate‑homeostasis which are associated with cardiac disorders such as ventricular arrhythmias that cannot be treated by conventional therapy, increased sensitivity to digoxin, coronary artery spasms, and sudden death. Additional concurrent symptoms include neuromuscular and neuropsychiatric disorders. Hypermagnesemia is found in acute and chronic renal failure, magnesium excess, and magnesium release from the intracellular space.
Source: Roche Cobas MG2 Method Sheet Version 3.0 2023-11
Methodology
Colorimetric endpoint method (Roche Cobas c503/c303)
Sample Type
| Preferred Sample Type | |
|---|---|
| Light green top - Plasma | |
| Acceptable Sample Type(s) | |
|---|---|
| Dark green top - Plasma | |
| Yellow top - Serum | |
| Red top - Serum | |
Centrifuge: Yes
Specimen Minimum Volume
55 uL with insert cup
Specimen Stability
| Temperature | Time |
|---|---|
| Ambient (15-25°C) | 7 days |
| Refrigerated (2-8°C) (store) | 7 days |
| Frozen (-15 to -25°C) | 1 year* |
Separate plasma or serum from cells within 2 hours.
*Freeze only once!
Reference Ranges
| Normal Range | |
|---|---|
| <60 years | 1.6 - 2.6 mg/dL |
| >60 years | 1.6 - 2.4 mg/dL |
| Critical Values | |
|---|---|
| Non OB Patients | <1.0 or >4.0 mg/dL |
| OB Patients | <1.0 or >6.5 mg/dL |
| Technical Range |
|---|
| 0.3 - 4.86 mg/dL |
Rejection Criteria
| Hemolysis | Index >800 |
|---|---|
| Icterus | Index >60 |
| Lipemia | Index >2,000, ultracentrifuge |
Availability
| Performed | STAT |
|---|---|
| 24/7 | Yes |
Performing Laboratory
MultiCare Yakima Memorial Hospital Laboratory
MultiCare Cancer Care (NSL)
Lab Department
Chemistry
CPT Code
83735
LOINC
19123-9 Magnesium [Mass/Vol]