Definition
A cross-allergy is a form of allergic reaction. In an allergic reaction, certain antibodies (IgE antibodies) react to an allergen (for example pollen) and an allergic reaction occurs, for example in the form of a skin rash or irritation of the mucous membranes with itchy eyes and increased sneezing. In the case of a cross-allergy, the antibody triggers an allergic reaction not only on contact with the original allergen (for example pollen) but also on contact with certain other allergens (for example kiwis). It is very different from person to person whether and to what extent a cross-allergy exists and which other allergens it includes.
Causes
When the human body is confronted with an allergen, it can produce antibodies to this allergen in the case of increased sensitivity. An allergic reaction then occurs with each new exposure to the allergen. The antibodies recognize special patterns on the surface of the allergen.
When they bind or couple to these patterns, an immune reaction is triggered which leads to the allergic reaction. The antibody recognizes the pollen on the surface of which it can dock and triggers an immunological reaction and the affected person notices that he or she has red, itchy eyes. In case of a cross-allergy, the antibody also binds to patterns on the surface of allergens. However, they are not exactly the same as those of the original allergen, but are very similar to them. This leads to the fact that even substances which originally would not have caused an allergic reaction now do so.
Allergens and possible cross allergens
Birch Other pollen: Beech, alder, oak, ash, hazel Foods: nuts, carrots, tomatoes, soya, many kinds of pome and stone fruit, strawberry, parsley, pepper Cereal pollen Other pollen: Ryegrass, cereals (such as wheat, spelt, barley, oats, millet, corn, rice) Food: Cereal flour Grasses Grasses Other pollen: Cocksfoot, Smoke grass, Timothy grass Cereals: oats, barley, rye, wheat Foods: raw potatoes, pulses, kiwi, (water) melon, tomatoes, peas, peppermint, various herbs Mugwort Other pollen: Birch, chamomile, dandelion, daisies, sunflower Foods: peppers, celery, carrots, potatoes, cucumber, kiwi, apple, many common spices and herbs etc Ash Further pollen: Lilac, Privet, Olives Lilac Ash Grapesweed Foods: Banana, Melon, Camomile Nuts Other nuts: Cashew, Hazelnut, Almond, Poppy, Pistachio, Sesame, Walnut Foods: Peanut, Strawberry, Kiwi Pulses Other Pulses: Bean, Peanut, Lentils, Soy, Lupine Kiwi Pollen: Mugwort, birch, grass Foods: Pineapple, apple, carrot, potato, rye and wheat flour, latex celery pollen: Mugwort, birch Foods: carrot, many common spices Cow’s milk Foods: beef and veal, soy, beef hair Dust mites Foods: mainly crustaceans such as, shrimps, lobsters, crabs, crabs, shrimps etc. ; oysters, snails Latex pollen: Mugwort, ragweed, timothy grass Foods: avocado, raw potatoes, peppers, celery, tomato, banana, kiwi, mango, peach etc. Penicillin Other antibiotics: Cephalosporins
