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. The reference range listed on the report is the lower limit of quantitation for the assay.
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||49720||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.
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.
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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.
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