An allergic reaction is the result of a response by the body’s immune system to the presence of a substance thought to be foreign and potentially harmful. Where the suspect substance is a viral or bacterial protein, such a reaction is an appropriate defence mechanism that is designed to incapacitate the invading organism in some way and limit the extent of infection. On occasions, proteins normally ignored by the immune system trigger an inappropriate response frequently causing a severe reaction. Known as allergens, these substances occur in the air, on surfaces, and in food. A simple allergy test will confirm who may be susceptible to this type of reaction and the allergen responsible

Depending on the allergen and its access route, reactions vary. Dermatitis, for instance, is a common response in some subjects to skin contact with certain detergents or cosmetics. Other subjects may present with respiratory difficulties after inhaling household dust or plant pollens. In more severe cases, the subject may experience an acute asthma attack. When an allergen is ingested, the consequences can sometimes be far more serious, and may even result in a life-threatening condition known as anaphylaxis. Among other things, nuts, shellfish, milk, and eggs are commonly responsible for food allergies, so any test regimen should, of course, include screening the subject for signs of susceptibility to these potential allergens.

The normal response by the immune system to the presence of a foreign protein is to form an antibody that will specifically negate its potentially harmful properties. The presence of that antibody in a given subject is an indication that he or she has experienced contact with the matching allergen. This is equally true, even when that allergen is a compound which the immune system has mistakenly identified as alien. Techniques for the detection, in body fluids or tissue, of antibodies to components of peanuts or prawns, for example, provide the basis for food allergy tests.

In this type of reaction, the antibodies produced belong to a class of proteins known as the immunoglobulins, specifically of the type designated IgE. Some individuals experience a far milder type of reaction to particular foodstuffs. This commonly manifests as bloating and abdominal cramps, and unlike an allergic reaction, only occurs a while after a meal. Although not an immune reaction per se, this intolerance, which commonly involves gluten or lactose, is also characterised by the production of specific antibodies. In such cases, however, the immunoglobulins are of the type know as IgG. Typically, food allergy tests are designed to detect and to differentiate both types of immunoglobulin, and can thus distinguish between potentially life-threatening allergies and the less serious problem of intolerance.

The potentially fatal consequences of an allergic reaction have prompted stringent regulations pertaining to the labelling of processed foods and beverages. Producers are responsible for confirming or precluding the presence of known allergens in their products, and drawing the attention of those who might be adversely affected.

With almost 40 years of experience in the specialised field of laboratory diagnostics, IEPSA serves the needs of the food and beverage industry with kits for the detection and assay of allergens in their products, and those of the consumer with a range of comprehensive and reliable food allergy test kits.

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