Diagnostic tests for food allergy

The diagnosis of food allergy is still based primarily on a detailed medical history and comprehensive physical examination. Clinical or laboratory tests only serve as an add-on tool to confirm the diagnosis. The standard techniques include skin prick testing and in-vitro testing for specific IgE-antibodies, and oral food challenges. Properly done, oral food challenges continue to be the gold standard in the diagnostic workup. Recently, unconventional diagnostic methods are increasingly used. These include food specific IgG, antigen leucocyte antibody and sublingual/intradermal provocation tests, as well as cytotoxic food and applied kinesiology and electrodermal testings. These lack scientific rationale, standardisation and reproducibility. There have been no well-designed studies to support these tests, and in fact, several authors have disproved their utility. These tests, therefore, should not be advocated in the evaluation of patients with suspected food allergy because the results do not correlate with clinical allergy and may lead to misleading advice and treatment.