1- Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar de Lisboa Central, EPE, Lisboa
- Allergy School Food Allergy Training Course 2015. El Escorial, Espanha; 24 a 26 de Setembro de 2015 - POSTER
Introduction: Food allergy has been considered a problem more and more urgent, particularly in childhood. The prevalence of allergy to individual foods varies with the dietary habits in different countries. Despite common in several countries, mustard allergy is rare in Portugal.
Case report: Male child, 8-years-old (y), followed in our consultation since he was two for cow’s milk and egg allergy (overcome). At 2.5y he reported an urticarial reaction, with angioedema of the face, after the ingestion of a pesto sauce made with cashew; in this context he performed skin prick tests (SPT), that were positive to peanut, hazelnut, walnut, cashew and pistachio, so we advised dietary avoidance of peanut and tree nuts. At 7y, he presented an episode of urticaria (of the face), conjunctivitis, hitching of the mouth ad gastric pain after a meal seasoned with mustard. One hour later, he had diarrhoea too. Clinical resolution was observed, 2 hours later, after the administration of cetirizine. In the previous summer, the patient had been to a party where he had eaten hot-dogs with mustard, with no documented reactions; he had never eaten mustard before. Skin prick-prick tests with 3 different varieties of mustard were positive (negative in 6 controls). Strict dietary avoidance was started, with no more episodes of accidental ingestion or reactions.
Discussion: We presented a case report of mustard allergy in a patient primarily sensitised to tree nuts. Mustard belongs to the Brassicaceae family. Four allergens from yellow mustard have been identified: Sin a 1 (S2 albumin), Sin a 2 (11S globulin, that share epitopes with the majority of tree nuts), Sin a 3 (LTP) and Sin a 4 (profillin). In this case, sensitization to mustard appeared after peanut and tree nuts allergy, which could be the result of cross-reaction to Sin a 2. Component resolved diagnosis would help to understand this possible relation. The primary therapeutic strategy in the management of mustard allergy is avoidance of the culprit allergen; however avoidance could be difficult because mustard is a common hidden allergen. Education of all family members to the risks of contamination is mandatory.
Palavras Chave: Food allergy, childhood, tree nuts allergy, mustars allergy