Giant Ragweed, Short Ragweed, Western Ragweed
Establishing a diagnosis of an allergy to giant ragweed, short ragweed, and Western ragweed
Defining the allergen responsible for eliciting signs and symptoms
-Responsible for allergic disease and/or anaphylactic episode
-To confirm sensitization prior to beginning immunotherapy
Testing for IgE antibodies is not useful in patients previously treated with immunotherapy to determine if residual clinical sensitivity exists, or in patients in whom the medical management does not depend upon identification of allergen specificity.
This multi-allergen IgE antibody panel, combined with measurement of IgE in serum, is an appropriate first-order test for allergic disease.
It requires less specimen volume and less cost for ruling out allergic response; however, individual (single) allergen responses cannot be identified. In cases of a positive test, follow-up testing must be performed to differentiate between individual allergens in the panel.
Note: Only one result is generated for each panel.
Some individuals with clinically insignificant sensitivity to allergens may have measurable levels of IgE antibodies in serum, and results must be interpreted in the clinical context.
False-positive results for IgE antibodies may occur in patients with markedly elevated serum IgE (>2500 kU/L) due to nonspecific binding to allergen solid phases.
Since only one result is generated for this panel, individual (single) allergen responses cannot be identified. When this panel is positive, follow-up testing is required to differentiate between individual allergens in the panel.
Reference values apply to all ages.
Positive results indicate the possibility of allergic disease induced by one or more allergens present in the multi-allergen cap.
Negative results may rule out allergy, except in rare cases of allergic disease induced by exposure to a single allergen.
Detection of IgE antibodies in serum (Class 1 or greater) indicates an increased likelihood of allergic disease as opposed to other etiologies and defines the allergens that may be responsible for eliciting signs and symptoms.
The level of IgE antibodies in serum varies directly with the concentration of IgE antibodies expressed as a class score or kU/L.