A remarkable food allergy in children: cashew nut allergy

The prevalence of cashew nut allergy is increasing. Clinical reaction to cashew nuts may be severe, including anaphylaxis. In this study, we aimed to evaluate the frequency of cashew nut sensitivity in a group of children with food allergy and the clinical features and course of cashew nut allergy.

A retrospective chart review was performed on 516 children who presented with food allergy at a pediatric allergy department. Individuals sensitized to cashew nuts were examined.

Cashew nut sensitization was detected in 17 (64.7% male; mean age of symptom onset, 14 months) of 516 patients with food allergy. Skin symptoms were the most frequent clinical presentation, followed by gastrointestinal symptoms. Overall, 29.4% of the patients presented with anaphylaxis. All anaphylactic reactions were developed after the first consumption of cashew nuts. Of the cashew nut-sensitized patients, 82.3% were diagnosed with moderate-to-severe atopic dermatitis, and all of them had multiple food allergies. During the follow-up, 90% of the patients who had cashew nut sensitization and co-existing food allergies to cow's milk and/or hen's egg developed tolerance to cow's milk and/or hen's egg, but none of the patients could tolerate cashew nut ingestion.

Cashew nut is a potent allergen, causing severe allergic reactions that persist long term compared with other food allergies. Early onset of moderate-to-severe atopic dermatitis and multiple food allergies are remarkable co-existing conditions in children who have been diagnosed with cashew nut allergy. Pediatricians should be aware of this emerging food allergy.