An elevated concentration of total immunoglobulin E (IgE) is not diagnostic for allergic disease, and must be interpreted in the clinical context of the patient, including age, gender, travel history, potential allergen exposure, and family history.
A normal concentration of total IgE does not eliminate the possibility of allergic disease. In patients with a high index of suspicion for allergic disease, testing for allergen-specific IgEs may be warranted.