The diagnosis of food allergy
Posted by admin on June 16th, 2009
The diagnosis of food allergy requires a careful history, physical examination, selective skin or serum IgE antibody tests in cases of suspected IgE-mediated disorders, appropriate exclusion diets, and sometimes blinded provocation challenges. At present, there is no evidence of the diagnostic utility for the following assays: quantitation of food-specific serum IgG or IgG4 antibodies, serum food antigen-antibody complex assays, cytotoxic food testing, tests of lymphocyte activation (proliferation, interleukin-2, or leukocyte inhibitory factor studies), or sublingual or intracutaneous neutralization or provocation.
Once food allergy or hypersensitivity has been diagnosed definitively, the only proven form of therapy is strict elimination of the offending food. This requires considerable time (and ideally a dietitian) to educate the patient on spotting all forms of “hidden foods” and assuring a nutritionally sound diet. Teaching patients to read food labels is necessary to ensure good compliance with an elimination diet. About Affective Disorders.
Patients who have IgE-mediated food allergies also must be prepared to treat accidental ingestions; this includes using injectable epinephrine and oral liquid antihistamines. In addition, patients must be prepared to go to the nearest emergency facility for further treatment when indicated.
The role of breastfeeding and food allergen avoidance in the prevention of atopy and food allergy remains controversial. However, it appears that breastfeeding (especially when the mother avoids major allergens – milk, egg, peanut, fish – during lactation) and/or the use of hydrolyzed infant formulas can prevent some atopic dermatitis and food allergy in high-risk infants, but whether it actually prevents respiratory allergy is not yet clear.
Tags: allergic diseases, allergy, food allergy