Pine Nut Allergy Test
Latin name: Pinus edulis
Common names: Pine nut, Pignoles, Pinon nut, Pignola, Pinyon nut, Pine kernels
Pine nut is a food which may result in allergy symptoms in sensitised individuals.
Pine Nut Allergy Test: Allergen Exposure
Pine nuts come from within the cones produced by the numerous varieties of pine tree, and can be found in abundance in south-western North America, but also in similar climates elsewhere, most notably the Mediterranean.
They are obtained from the pine cone by heating it, which then yields several small, high-fat, high-protein, ivory-coloured nuts. They must subsequently be removed from their individual shells before use, a delicate and time consuming process which contributes to the expense of this foodstuff.
Several varieties exist, including the Italian or Mediterranean and the Chinese.
Pine nuts are often sold as a health product. They are used raw and intact, ground up, and for oil. They are popular as a snack, in salads, and in sweet and savoury local dishes, especially the pesto and as a seasoning in the cuisine of the Mediterranean area of Spain.
Pine Nut Allergy Test: Allergen Description
No allergens present in pine nut have yet been characterised, although a number of proteins have been isolated. An important allergenic band has also been reported.
Pine Nut Allergy Test: Potential Cross-Reactivity
An extensive cross-reactivity among the different individual species of the genus could be expected. Cross-reactivity between the botanically related seeds of Pinus pinea and P. cembra has been demonstrated.
It was postulated, based on the cross-reactivity between pine nut and pine pollen extracts, that co-sensitisation to these allergens could be the reason for a case of pine nut allergy described in a single patient with pine pollen allergy.
However, the allergens were not studied in this case, and among individuals who had experienced anaphylactic reactions to pine nut, none were pine tree pollen-allergic.
Studies have also reported the existence of common antigenic proteins between pine nut and peanuts, and cross-reactivity between pine nut and almond.
Pine Nut Allergy Test: Clinical Experience
Pine nut may commonly induce symptoms of food allergy in sensitised individuals. Reactions may be severe. Anaphylaxis after pine nut ingestion has been often reported.
Acute anaphylaxis after skin testing for pine nut was reported in a 20-year-old woman. Her initial complaints were that she had developed generalised urticaria, swelling of the face and dyspnoea after eating a salad containing pine nuts.
A 22-year-old man, without a history of atopy or drug allergy, presented with difficulty in breathing and swallowing, profuse sweating, abdominal pain, and visual disturbances 15 minutes after eating several pine nuts.
Anaphylaxis to pine nuts was described in a 53-year-old man, who experienced angioedema, acute dyspnoea and circulatory collapse for the first time after a meal of spaghetti and pesto sauce (olive oil, herbs, pine nuts and sardines). Skin reactivity was demonstrated for pine nut but not for the other ingredients. Ten minutes after an oral challenge of a teaspoonful of pine nuts, he developed marked conjunctival inflammation and periorbital itching and reddening.
Two young girls who experienced anaphylaxis caused by small amounts of pine nuts were described. Both girls were monosensitised to pine nut.