Hypersensitivity

Anaphylaxis is a syndrome including one or more of the following life-threatening responses: hypotension, bronchospasm, upper airway angio-oedema. Other manifestations such as urticaria or rhinitis may also occur. Anaphylaxis is due to release of mediators such as histamine or leukotrienes, this mediator release may be due to immunological or non-immunological mechanisms. Ethylene oxide (ETO) is used to sterilize haemodialysers and other medical equipment that cannot withstand heat sterilization. There is significant scientific evidence that ETO can haptenize human proteins such as human serum albumin (HSA), thus rendering the allergen ETO-HSA. Approximately two-thirds of patients who experience dialysis anaphylaxis have IgE against ETO-HSA, whereas only about 5% of those without anaphylaxis have IgE against ETO-HSA. No other allergens or mechanisms have been described to account for a significant number of anaphylaxis reactions.