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Test Code
CUINX
Test Name
Chronic Urticaria Index Test
CPT Codes
86343
Expected Turnaround Time
2 - 9 days
Clinical Utility

The CU Index test is the second generation Functional Anti-FceR test. Patients with a CU Index greater than or equal to 10 have basophil reactive factors in their serum which supports an autoimmune basis for disease.
Specimen and Container Info

Specimen Type: Serum

Preferred Collection Container: Gold Top, Serum Separator

Alternate Collection Container: Red Top, Plain

Desired Specimen Volume: 2 mL
Collection Instructions
  1. Collect a gold top, serum separator tube via venipuncture.
Processing and Submission Instructions
  1. Separate serum from cells within two hours of collection.
  2. Transfer 2 mL of serum to a clear aliquot tube (screw cap).
Patient Preparation
Patients taking calcineurin inhibitors should stop medication 72 hours prior to draw. Patients taking prednisone should be off their medication for 2 weeks prior to draw.
Transport Instructions

Transport to the laboratory refrigerated. 
Stability Requirements

Room Temperature

14 days

Refrigerated

14 days

Frozen

14 days
Methodology
Ex-Vivo Challenge, Cell Culture, And Histamine Analysis
Reference Intervals

See patient portal.
Limitations

A positive result does not indicate which autoantibody (anti-IgE, anti-FceRI or anti-FCERII) is present.
Alternate Names
  • FCUIX
Reference Lab
Mayo Clinic Laboratories
Testing Schedule
Routine, 2 times per week
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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