Idiopathic anaphylaxis in children

Background: Idiopathic anaphylaxis is a disease where no identifiable antigen or disease initiates an anaphylactoid reaction. Unlike classic IgE antibody-mediated anaphylaxis, severe idiopathic anaphylaxis is treatable with corticosteroids. To date, only 22 pediatric cases from one referral center have been reported. Objective: To describe the characteristics of children with idiopathic anaphylaxis Methods: A retrospective review of medical records for children presenting to the pediatric allergy clinic with the diagnosis of idiopathic anaphylaxis was performed. Results: The review identified eight children with idiopathic anaphylaxis. All eight patients had a cutaneous finding of either urticaria, angioedema, or generalized flushing. Six of the eight patients were noted to have wheezing or angioedema of the airway causing respiratory difficulties. Diarrhea was noted among six patients. Many of the children clearly had life threatening events. Response to appropriate therapy was generally good. Conclusions: Pediatric idiopathic anaphylaxis can present at any age. It may be that many pediatric cases are assumed to be anaphylaxis due to some unknown antigen, and the correct diagnosis is never appreciated. It is important to recognize this disease in children so that it may be appropriately treated, because its specific therapeutic regimen has been shown to prevent the potentially fatal consequences of this disease.