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Test Code
RCRP
Test Name
Magnesium, RBC
CPT Codes
83735
Expected Turnaround Time
2 - 4 days
Clinical Utility

Evaluate magnesium deficiency
Specimen and Container Info

Specimen Type: Red Blood Cells (RBCs)

Collection Container: Royal Blue Top (EDTA)

Alternate Collection Container: Green Top (Sodium or Lithium Heparin) or Lavender Top (EDTA)

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect specimen in royal blue top (EDTA) tube via venipuncture.
Processing and Submission Instructions
  1. Separate plasma from red blood cells as soon as possible.
  2. Discard the plasma.
  3. Submit only the RBCs in the original collection container.
Transport Instructions

Transport to the laboratory refrigerated. 
Stability Requirements

Room Temperature

14 days

Refrigerated

14 days
Causes for Rejection
  • Serum or plasma specimen
Methodology
Atomic absorption spectrometry (AAS); inductively-coupled plasma/mass spectrometry (ICP/MS)
Reference Intervals

 See patient report.
Alternate Names
  •  Mg, RBC
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Monday-Friday
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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