Holy Guacamole! I have avocado allergy!
The avocado (Persea americana) is native to Mexico and Central America. The avocado tree belongs to the family Lauraceae along with cinnamon, camphor and bay laurel. Sometimes avocados are called “alligator pears” based on their shape and rough texture of the skin. The edible avocado is a “fruit” with a large (and slippery) seed. The oldest avocado dates back to 10,000 BC in Puebla, Mexico. In the U.S. about 95% of all avocados are grown in Southern California and most of these in San Diego County.
Avocados are eaten fresh, cut into salads, on sandwiches and used in guacamole. Avocado is especially important in vegetarian dishes. Avocado contains high amounts of fat including monounsaturated fat. Quite frankly, they are delicious!
Latex-fruit syndrome: This is the most common presentation of avocado allergy including anaphylaxis from eating avocado. Persons with latex allergy (especially health care workers and spina bifida patients) are more likely to have avocado allergy as well as allergic reactions to kiwi, banana, chestnut and other foods. The reactions can be severe including skin reactions (hives, itching, swelling), respiratory (asthma, cough, wheezing, chest tightness), vomiting, allergic rhinitis or anaphylaxis. Nurses with latex allergy are almost 10x more likely to develop avocado allergy. The causative protein that is shared between latex (Hevea) and avocado is a Class I endochitinase named Hev b 6.02.
Pollen-Food Allergy Syndrome: After ingestion of fresh avocado, the mouth, palate and throat feels itchy with mild swelling of the tongue and throat but rarely anaphylaxis. In children with grass pollen, they may have cross reactivity to latex allergens but are not likely to develop symptoms on latex exposure. This very common allergen (pan-allergen) is called profilin and shared between pollen and fruits.
Food allergy without latex allergy: Severe allergy (anaphylaxis) to avocado without co-sensitization to latex is rare. In 2011, a case report of a 15-year-old boy who had an anaphylactic reaction 30 minutes after ingestion of guacamole containing avocado was published. He did not have latex allergy. He had a positive allergy skin test to fresh and commercial extract of avocado. This article can be found at: http://www.ncbi.nlm.nih.gov/pubmed/2166364 In an Italian study published in 2009, only 1 of 1110 adults with food allergy had avocado allergy.
Rash: Allergic contact dermatitis occurred in a patient who applied a sunscreen containing avocado oil.
At Family Allergy Asthma & Sinus Care, we specialize in not only the common food allergies, but the rare food allergies as well. Theoretically, any food may cause an allergic reaction. While avoidance is the best treatment, it is very important to have self -injectable epinephrine available as well for acute, severe reactions. Happy Cinco de Mayo weekend!