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Test Code
WALN4
Test Name
Walnut IgG4
CPT Codes
86001
Expected Turnaround Time
2 - 3 days
Clinical Utility

The clinical utility of food-specific IgG4 tests has not been clearly established. Physicians sometimes use allergen-specific IgG4 to evaluate patients prior to or during immunotherapy. These tests can be used in special clinical situations. This test should only be ordered by physicians who recognize the limitations of the test.
Specimen and Container Info

Preferred Specimen Type: Serum

  

Preferred Collection Container: Red Top, Plain

Alternate Collection Container: Gold Top, Serum Separator

Desired Specimen Volume: 0.5 mL
Collection Instructions
Collect specimen in serum separator tube or red top tube via venipuncture. Centrifuge and transfer serum to aliquot tube.
Transport Instructions

Transport to the laboratory refrigerated.

Stability Requirements

Room Temperature

1 week

Refrigerated

4 weeks

Frozen

4 weeks
Methodology
Enzyme Immunoassay
Reference Intervals

mcg/mL of IgG4

Lower Limit of Quantitation

0.30

Upper Limit of Quantitation

30.0

 
Reference Lab
Viracor Eurofins
Testing Schedule
Varies
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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