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.
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 (>2,500 kU/L) due to nonspecific binding to allergen solid phases.