Sweet chestnut is a food which may result in allergy symptoms in sensitised individuals.

Sweet Chestnut Allergy Test: Allergen Exposure

The sweet chestnut tree is native to southeastern Europe, parts of Asia, and North Africa. Currently, the principle producers of edible sweet chestnuts are China, Korea and Italy, followed by Spain, Portugal, France, and Greece.

When raw, sweet chestnuts have a bitter taste, which improves with cooking, developing into a sweet and nutty flavour, with a texture like a firm baked potato – unlike other nuts, which are crunchy.

Edible chestnuts have been grown for culinary purposes for centuries and can be consumed fresh, boiled, grilled, or roasted. They can be frozen or pureed for desserts or confectionery, or used in stuffing or as a garnish. Dried chestnuts should be soaked in water, cooked, and then treated as fresh.

Traditionally, chestnuts are roasted over an open fire or in the oven. They can be dried, ground and used as flour in breads and puddings, or as a thickener in soups. The roasted nut can be a coffee substitute.

They are low in fat, with as little as 2% oil content – by comparison many edible nuts are around 50% oil – and have no cholesterol.

Sweet Chestnut Allergy Test: Allergen Description

A number of allergens present in sweet chestnut have been characterised to date, including a chitinase and a lipid transfer protein, both major allergens.

Although chestnut allergy is strongly associated with latex-fruit syndrome, chestnut allergy may occur independently of this syndrome.

Sweet Chestnut Allergy Test: Potential Cross-Reactivity

A number of plant protein families have been shown to be involved in latex-fruit syndrome, including avocado, banana, sweet chestnut, kiwi, peach, tomato, potato, bell pepper, fig, pineapple and peanut.

However, few studies address actual allergy to chestnuts in patients reacting primarily to this food.

In one study of 22 people with proven allergy to chestnut, the age of onset of reactions to chestnut ranged from 5 to 70 years, with 36% having experienced severe anaphylactic episodes.

A review of 28 cases of sensitisation to latex showed that banana- and chestnut-induced allergies were the allergies most frequently associated with latex-induced allergy.

Sweet Chestnut Allergy Test: Clinical Experience

Allergy to chestnut on its own is infrequent, considering how common consumption is in certain countries.

Oral allergy syndrome induced by chestnut, followed by rhinoconjunctivitis and asthma, has been described in a 22-year-old woman.

She reported that when chewing chestnut, she had felt a burning sensation and itching of the oropharyngeal mucosa followed by lacrimation, nasal pruritus, violent sneezing salvos, and “moderate” difficulty in breathing, but not severe enough to require treatment.

Symptoms initially had been relatively minor and limited to oral ones, but subsequent episodes became progressively worse.

A 4-year-old boy developed ocular itching, eyelid and lip angioedema, unproductive cough, wheezing and dyspnoea immediately after peeling and eating an oak acorn. Months later, he experienced similar symptoms after eating a chestnut.

Chestnut has been reported to cause urticaria-angioedema in a 29-year-old man.

Other reactions

Chestnut tree pollen is an aeroallergen.