Two of the antibodies involved in allergic reactions are immunoglobulin E (IgE) and immunoglobulin G (IgG). Measuring antigen-specific antibodies can help in the assessment of allergies, particularly food allergies. One study of young children found that 62.5% of children with symptoms of food allergy had specific IgG antibodies and 22.9% had specific IgE antibodies, while the children without symptoms had neither (Hofman T. IgE and IgG antibodies in children with food allergy. Rocz Akad Med Bialmyst 1995;40(3):468-473).
IgE production occurs right after ingestion or inhalation of an allergen and is referred to as a Type I immediate hypersensitivity reaction. Typical reactions include sneezing, itching of the palate or ears, runny nose, itchy eyes, and fatigue. Ingestion of an antigen may lead to symptoms such as asthma, skin rash, hives, abdominal cramps, diarrhea, and in severe cases, anaphylaxis. The allergic reaction occurs within two hours of exposure to the antigen, therefore it is usually easy to recognize the link between the allergen and the symptoms. Testing for IgE reactions would be performed through a referral by your medical doctor for skin scratch testing.
IgG antibodies are produced for several hours or days after exposure to an allergen and are called Type III delayed hypersensitivity reactions. IgG forms an immune complex with the allergen, causing the release of inflammatory mediators wherever the immune complex is deposited. This process takes anywhere from several hours to several days, which is why hypersensitivity reactions are delayed. Because of this delay, it can be hard to detect the relationship between the food and the symptoms. Typical reactions may include headaches, fatigue, runny nose, asthma, recurrent infections (e.g. sinusitis, ear infections, tonsillitis, respiratory tract infections), skin reactions including hives, eczema and other skin conditions, and muscle or joint pain. As well, some health conditions may be worsened by delayed hypersensitivity reactions. The IgG antibody test can be useful for determining reactive foods.
This comprehensive analysis of 96 different foods can help your naturopathic doctor to accurately diagnose food allergies. With the Allergy Antibody Assessment, IgG levels are assessed using an Enzyme-Linked Immunosorbent Assay (ELISA). This advanced immunological procedure uses an enzyme binding process to detect antibody levels. It is a highly sensitive test ordered via Ontario labs.
At our naturopathic health clinic we use IgG testing when indicated, in the context of naturopathic care, to provide a simple and practical means for uncovering potential causes of allergic reactions and allergy related disease.
Note: this test is only provided to patients of Family Naturopathic Clinic, when indicated. It cannot be ordered as a stand-alone test.