Mushroom (champignon) is a food which may result in allergy symptoms in sensitised individuals.

Mushroom Allergy Test: Allergen Exposure

There are approximately 14,000 described species of mushrooms. The main types of these mushrooms are agarics (e.g. the button mushroom), boletes, chanterelles, tooth fungi, polypores, puffballs, jelly fungi, coral fungi, bracket fungi, stinkhorns, and cup fungi.

‘Toadstool’ refers to those mushrooms with poisonous fruiting bodies, and to other minor macrofungi. Except for the toadstools, mushrooms have various degrees of immunomodulatory, lipid-lowering, anti-tumour and other beneficial health effects, without any significant toxicity.

Today’s commercial variety of the champignon (also known as the button mushroom) was originally a light brown colour, but mutated into the type with white caps which has now become the predominant commercial variety.

Mushrooms are purchased fresh or canned or pickled. They can be found cooked in pizzas and casseroles, raw on salads, and in a variety of other dishes. Although the mushroom is a fungus, it is used as a vegetable in cooking.

Mushroom Allergy Test: Allergen Description

No allergens from mushrooms have yet been characterised.

It is not known whether allergens in the spores are similar to those in the mushroom itself. In a study of Coprinus quadrifidus, common allergenic epitopes were demonstrated by inhibition of spore RAST by spore, cap, and stalk extracts, suggesting that cap and stalk extracts contain allergens similar to those in spore extract.

It may well be that common and unique allergens are found in spores, caps and stalks.

Mushroom Allergy Test: Potential Cross-Reactivity

The cross-reactivity of this allergen has not yet been fully explored. Enolases are considered to be highly conserved major fungal allergens, but whether these panallergens occur in the champignon mushroom has not been evaluated yet.

An unusual relationship was shown between allergenicity to moulds (Alternaria alternata, Cladosporium herbarum and/or Aspergillus fumigatus), and the presence of skin-specific IgE to champignon mushroom and/or spinach.

Cross-reactivity was demonstrated between spinach and champignon mushroom. The authors suggested that this was due to common epitopes.

Mushroom Allergy Test: Clinical Experience

Mushroom may uncommonly induce symptoms of food allergy in sensitised individuals. Fungal components can cause allergic symptoms through inhalation, ingestion or skin contact. Whereas respiratory allergy is thought to be induced by spores, allergic reactions following ingestion are attributed to other parts of the mushroom.

Reports of allergy to champignon mushroom are very uncommon, which could indicate either that reactions are uncommon to this particular mushroom or that reactions have been rare because until recently this mushroom was not frequently used in meals.

Anaphylaxis to mushroom has been reported.

Airborne occupational allergic contact dermatitis from champignon mushroom in a 31-year-old mushroom picker was reported.

Other reactions

Hypersensitivity pneumonitis (allergic alveolitis) and eosinophilic bronchitis are important occupational diseases in mushroom workers, affecting those active in cultivation, picking, and packing of commercial mushroom crops.

Workers cultivating mushrooms are exposed to various fungi when handling the mushroom compost and develop a condition known as mushroom grower’s lung, manifestations of which are pneumonitis and bronchitis.

Asthma and rhinitis to mushroom spores may occur.