Abstract
As a consequence of the general increase in allergic sensitization, the prevalence of hypersensitivity reactions to multiple foods has become a significant clinical problem in these days. It was explained that the shared homologous proteins in foods caused these cross reactions. The frequency of clinical allergy caused by cross-reacting proteins and panallergens appear to be increasing and resulted in the increases of allergic diseases and allergen sensitization.
Recently, the rate of fish, shellfish, and fish roe allergy is increasing in even Japanese children. To determine the risk of reaction to related foods, clinical evaluations such as a careful history taking, laboratory evaluation, and oral food challenges are indispensable. The evaluation of food allergens is limited by high false-positive rate of CAP-RAST® scores and skin test results, and they are complicated by cross-reactive proteins.
In this report we evaluated specific IgE antibody against hen's egg white, fish, shellfish, and fish roe in 79 children suspected of food allergy. And we found that positive rate of CAP-RAST® scores between egg white and fish roe, and between fish and its fish roe were not correlative (p>0.05). The IgE antibodies against fish, shell fish, and fish roe detected by CAP-RAST® appeared to have relatively low specificity. Therefore, it was difficult to predict allergic reactions against these foods by the data of CAP-RAST® scores. Positive results with skin test or CAP-RAST® need to be confirmed by diet elimination and/or oral challenges except for the severe cases. Careful diagnosis is recommended for avoiding malnutrition caused by an unnecessary dietary restriction.
