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Test Code
INSUI
Test Name
Insulin, Intact LC/MS/MS
CPT Codes
83525
Expected Turnaround Time
3 - 5 days
Clinical Utility

Help evaluate the likelihood that an individual has clinically significant insulin resistance or help in differential diagnosis (e.g., insulinoma versus exogenous insulin administration. The results of this test should be interpreted in the context of pertinent clinical history and physical examination findings.
Specimen and Container Info

Specimen Type: Serum

Preferred Collection Container: Gold Top, Serum Separator

Alternate Collection Container: Red Top, Plain

Desired Specimen Volume: 0.5 mL

Collection Instructions
  1. Collect a gold top, serum separator tube via venipuncture.
Processing and Submission Instructions
  1. Allow specimen to clot completely.
  2. Separate serum from cells.
  3. Transfer 0.5 mL of serum to a clear aliquot tube (screw cap).
Patient Preparation

Overnight fasting is required.
Transport Instructions

Transport to the laboratory refrigerated.
Stability Requirements

Room Temperature

24 hours

Refrigerated

28 days

Frozen

28 days
Causes for Rejection
  • Hemolysis
Methodology
Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS)
Reference Intervals

See patient report.
Reference Lab
Quest Diagnostics Nichols Institute
Testing Schedule
Routine, Monday - Saturday
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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