Diagnosing food allergy in children, peanuts?

Food allergy has a major impact on quality of life of children and their parents. Although food allergic patients usually do not experience daily symptoms, they are faced with dietary restrictions and the risk for a severe reaction every day. A correct diagnosis of food allergy is important to prescribe adequate emergency medication, educate children and their families in avoiding allergens and other triggers and prevent severe reactions. Excluding food allergy can be important to improve quality of life and prevent children from unnecessary elimination diets. In this thesis we aimed to: 1) investigate the impact of food allergy in children; 2) predict the presence and severity of peanut allergy during food challenges; 3) investigate and improve the diagnostic accuracy of food challenges and 4) evaluate post-food challenge outcomes. A nationwide electronic data collection system with validated questionnaires on respiratory and allergic diseases: the Electronic Portal was developed (chapter 2). This Electronic Portal was used to investigate the impact of atopic comorbidities and food allergy related characteristics on quality of life in children referred for food allergy (chapter 3). The current knowledge and advances of the use of CRD to predict the presence and severity of peanut allergy was described as an introduction of the second part of this thesis (chapter 4). In a retrospective study of 225 children who underwent a food challenge for peanut we investigated whether we could predict positive and/ or severe challenge outcomes (chapter 5). In a prospective study of 83 children with suspected peanut allergy we evaluated whether we could predict or exclude peanut allergy using sIgE and the basophil activation test to peanut components Ara h 2 and h 6 (chapter 6). The accuracy of food challenges was evaluated by investigating the degree of variability in the interpretation of symptoms during challenge between and within observers (chapter 7). Furthermore, it was evaluated whether monitoring of vital and respiratory parameters contributes to the accuracy of food challenges (chapter 8). The added value of open challenges and guided introduction after negative peanut challenge was investigated by follow up of the children participating in our prospective study (chapter 9). Furthermore, introduction success after negative peanut challenges of our retrospective study was evaluated to determine long term food challenge outcome (chapter 10). The implications and future perspectives of this thesis are discussed in chapter 11. This thesis demonstrates that the diagnostic procedures in children with suspected food allergy can be improved. Thorough examination and adequate management of allergic comorbidities in children referred for food allergy is warranted to improve generic quality of life. In 60% of children sIgE to Ara h 2 could be used to predict the presence or absence of peanut allergy. sIgE to Ara h 2 should therefore be implemented and used as a first step to start guided reintroduction or select children for food challenges. In part of the children food challenges will remain necessary for diagnostic purpose or to determine severity of peanut allergy. To establish unambiguous food challenge outcomes, challenges should be continued despite subjective symptoms if possible and open challenges and follow-up of introduction should be performed.