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

Abalone Allergy Test: Allergen Exposure

Abalone are a type of marine snail, and are found worldwide in coastal zones, with the exception of the Atlantic coast of South America, the Caribbean, and the East Coast of the United States.

They are recognisable by their characteristic low, open spiral shell, with a row of respiratory pores near the shells edge.

Abalone have been used as a food source by humans for thousands of years, and are considered a delicacy or luxury item in Latin America (particularly Chile), France, New Zealand, East Asia and Southeast Asia.

In Japan, live and raw abalones are used in awabi sushi, or served steamed, salted, boiled, chopped, or simmered in soy sauce. In California, abalone is used as a pizza topping, sauteed with mango, and also served in the form of steaks.

Abalone provides a good source of vitamin E (alpha tocopherol), thiamin, vitamin B12, iron, magnesium and phosphorus, and a very good source of protein, vitamin K, pantothenic acid and selenium.

Abalone Allergy Test: Allergen Description

A number of allergenic proteins have been isolated, and two major allergens have been characterised, including a tropomyosin.

As in other molluscs, abalone allergens are heat stable.

Abalone Allergy Test: Potential Cross-Reactivity

Cross-reactivity between different species of abalone is likely.

Allergy to abalone is most often associated with allergy to other related molluscs. Cross-reactions are found between molluscs, especially within the same class (bivalves, cephalopods or gastropods).

Therefore those allergic to bivalves (clams, mussels, oysters, and scallops) are likely to react to other bivalves, while those reacting to gastropods (abalone, limpets, snails, winkles and whelks) are likely to react to other gastropods.

Cross-reactivity has been demonstrated between common whelk and abalone.

Abalone Allergy Test: Clinical Experience

Adverse reactions following the ingestion of abalone range from mild oral allergy syndrome, to urticaria (which is probably the most commonly-reported symptom), to life-threatening systemic anaphylaxis.

Symptoms may involve nausea, diarrhoea, and asthma or rhinitis. Most symptoms occur within 90 minutes of ingesting the food, but delayed reactions have also been reported.

Symptoms have been reported on handling or inhaling steam from cooking molluscs, and asthma has been associated with workers opening mussels, suggesting that similar reactions may occur with abalone.

Anaphylaxis was reported to have resulted from abalone in a 30-year-old man, who described generalised oedema, dyspnoea and urticaria occurring immediately after eating raw fish and cuttlefish served on an abalone shell. He had a history of anaphylaxis after eating abalone.

In a study of 105 South African subjects, the four most common seafood species reported to cause adverse reactions were prawns (46.7%), crayfish (43.8%), abalone (35.2%) and black mussels (33.3%).

A Japanese study described 11 individuals who developed moderate to severe anaphylactic reactions following the ingestion of grand keyhole limpet and abalone.

Other reactions

The calcium carbonate dust created through the grinding and cutting of abalone is a respiratory irritant. Proteins left in the shell may trigger an allergic reaction.