8 hours
Test Updated:
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Test Overview
Colorimetric (Xylidyl Blue)
To aid in assessing cellular magnesium loss
50 - 200 mg/24 hrs (5-20 mMol/24 hrs). Random urine collections are reported in units of mg/dL, for which reference values are not established.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
24 hour urine collection. Instruct patient to void at 8:00am (or 8:00pm) and discard the specimen. Then collect all the urine including the final specimen voided at the end of the 24 hour collection period, i.e., 8:00am (or 8:00pm) the following day. Transport promptly to the laboratory. Container must be labeled with date and time collection started and finished. Refrigerate during collection.
Collect 24 hour urine in a clean, plastic container with no metal cap or glued insert and no preservative. Aliquot 5 mL urine into a clean, plastic container with no metal cap or glued insert and refrigerate. Record total 24 hour urine volume and collection dates/times on request form. Random urine also acceptable.