Food allergy to Helix terrestre (snail)

Area of Science:

• Allergy and Immunology
• Food Science
• Gastroenterology

Background:

• Food allergies are common, but allergies to specific foods like snails (Helix terrestre) are rare.
• Snails are a delicacy in certain European countries, including Spain, France, and Portugal.
• Limited research exists on snail-induced food allergies.

Purpose of the Study:

• To investigate the clinical characteristics and diagnostic methods of food allergy to Helix terrestre.
• To identify the specific type of mollusc responsible for the allergic reactions.
• To understand the primary affected organs and common symptoms in patients with snail allergy.

Main Methods:

• Retrospective analysis of 10 patients diagnosed with Helix terrestre food allergy over a 10-year period.
• Clinical evaluation of symptoms, including shock organ involvement (respiratory, skin, digestive).
• Diagnostic testing using skin tests and histamine release tests with various seafood allergens.

Main Results:

• The bronchial tree was the primary shock organ in 80% of patients.
• Most patients (6/10) did not exhibit typical digestive or skin symptoms.
• All patients reacted to Helix terrestre; two also reacted to Patella vulgata (limpet), both gastropods.
• Patients tolerated cephalopods and bivalves, suggesting a gastropod-specific allergen.
• Skin tests and histamine release tests proved effective for diagnosis.

Conclusions:

• Helix terrestre allergy primarily affects the respiratory system, differing from typical food allergy presentations.
• A specific protein found in gastropod molluscs is likely responsible for this food allergy.
• Skin and histamine release tests are valuable diagnostic tools for gastropod mollusc allergy.