Cashew allergy: observations of 42 children without associated peanut allergy

BACKGROUND: Cashew allergy seems to be increasingly frequent. The goal of the present study was to analyse the clinical features and results of investigations of 42 children with cashew allergy. METHODS: The clinical features and results of skin prick tests; specific IgE assays; and food challenges were analysed. RESULTS: The mean age at first allergic reaction was 2 years and the mean age at diagnosis of cashew allergy was 2.7 years. One in five children (12%) had a prior history of exposure to cashew nuts. Fifty-six per cent had skin symptoms; 25% had respiratory signs and 17% had digestive signs. Eighteen children had proven; associated food allergies (pistachio; seven; egg; five; mustard; three; shrimp; two; cow milk; one). The mean wheal diameter of the skin prick tests was 7 mm (3-16 mm) and the mean specific IgE level was 3.1 kUA/L (100 kUA/L). Eight children had positive food challenges. CONCLUSION: The increase in cashew allergy is worrying because it affects young children who may have a reaction without ever having been exposed to cashews. Almost one-third of children are allergic to pistachios; which belong to the same botanical family as cashews. Clinical history is generally and sufficiently suggestive to diagnose cashew allergy without recourse to food challenges.