The clinical utility of food-specific IgG tests has not been established. These tests can be used in special clinical situations to select foods for evaluation by diet elimination and challenge in patients who have food-related complaints. It should be recognized that the presence of food-specific IgG alone cannot be taken as evidence of food allergy and only indicates immunologic sensitization by the food allergen in question. This test should only be ordered by physicians who recognize the limitations of the test.
Enzyme immunoassay (FEIA). A standard curve is used to calculate the specific IgG concentrations. The calibrators are referenced to the International Reference Preparation for serum immunoglobulins. This test has not been cleared or approved for diagnostic use by the U.S. Food and Drug Administration.
3 business days from receipt of specimen
|Specimen Type||Order Code||CPT Code||NY Approved||Volume||Assay Range||Special Instructions|
|Serum||50420||86001||No||0.5 mL (min. 150 uL)||See Limit of Quantitation Guide||
The units are micrograms/mL of specific IgG. The reference varies by allergen.
|mcg/mL of IgG|
|Lower Limit of Quantitation||2.0|
|Upper Limit of Quantitation||200|
Reference ranges vary by allergen.
Specimens are approved for testing in New York only when indicated in the Specimen Information field above.
The CPT codes provided are based on Viracor Eurofins' interpretation of the American Medical Association's Current Procedural Terminology (CPT) codes and are provided for general informational purposes only. CPT coding is the sole responsibility of the billing party. Questions regarding coding should be addressed to your local Medicare carrier. Viracor Eurofins assumes no responsibility for billing errors due to reliance on the CPT codes illustrated in this material.
Position Statement 12 April 1990 published in Immunology and Allergy Practice.
Project Hope, Center for Health Affairs: "The Cost Implication and Cost Effectiveness of Allergy In Vitro Diagnostic Testing.", October 1988.
Hamilton, R and Adkinson, NF. Quantitation of allergen-specific IgE in serum using the RAST. Clin Immunoassay 1983; 6: 147-154.
Kelso,JM, Sodhi,N, Gosselin,VA and Yunginger,JW. Diagnostic performance characteristics of the standard Phadebas RAST, modified RAST, and Pharmacia CAP system vs skin testing. Annals of Allergy 67:511-514,1991.
Williams,PB, Dolen WK, Koepke, JW and Selner,JC. Comparison of skin testing and three in vitro assays for specific IgE in the clinical evaluation of immediate hypersensitivity. Annals of Allergy 69:48-52,1992.
Selner JC et al. Current issues relating to in vitro testing for allergen-specific IgE: a workshop report. Annals of Allergy 1999; 82:407 - 412.
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Williams PB et al. Analytical precision and accuracy of commercial immunoassays for specific IgE: establishing a standard. J Allergy Clin Immunol 2000; 105:1221 - 1230.
Szeinbach S et al. Precision and accuracy of commercial laboratories ability to classify positive and/or negative allergen-specific IgE results. Ann Allergy, Asthma & Immunol 2001; 86: 373 - 381.