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Lab Manual for UCSF Clinical Laboratories

Lab Manual for SFGH

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Item Value
Available Stat? Yes
Test code MG
Performed by? Chemistry
Sendout? no
Price range $
In House Availability Routine: 7 days;
STAT: 24 hours/ 7 days
Principle The assay is based on the reaction of magnesium with an indicator dye to form a colored complex. The amount of dye complex formed is proportional to the magnesium concentration.
Interpretation Magnesium is predominately an intracellular cation and is essential in enzyme reactions. Magnesium deficiency may cause weakness, tremors, tetany, and convulsions. Hypomagnesemia is associated with hypocalcemia, alcoholism, some types of malnutrition, malabsorption, chronic hemodailysis, and pregnancy. Increased serum magnesium concentrations occur in patients with renal failure, dehydration and Addison's disease.

Patient Preparation Fasting specimen.
Container type gel tube (gold or green top)
Amount to Collect 2 mL
Collection Instructions Hemolyzed serum will not be assayed.
Sample type Blood
Normal range 1.7-2.4 mg/dL (0.70-0.99 mmol/L)
Stability Serum stable at 4°C for 2 – 3 days; frozen, 6 months.
Additional information INDICATIONS: R/O tetany due to magnesium depletion; to monitor magnesium therapy for eclampsia.
References 1. Alfrey, A.C., Miller, N.L., and Butkus, D. Evaluation of body magnesium stores. J Lab & Clin Med, 84:153; 1974.

2. Bayer(TM) Clinical Methods Magnesium (5) B01-4148-01 Advia 1650 Operator's Guide. PN 073-5001-09. Last accessed June 2003. Siemens Medical Solutions Diagnostics, Malvern, PA.

CPT coding 83735
Last Updated 11/13/2010 1:14:05 PM
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