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 with-stand 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.