| Friday, February 6, 2009 |
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2. Causation of Anaphylaxis Antigens which are referred to allergens, are large molecules (usually proteins) that can be found on the surface of living organism (cells, viruses, fungi, bacteria) and non living substances (toxins, chemical, drugs and foreign particles). Anaphylaxis can occur in response to any allergen. When a patient is intact with an antigen, an allergic reaction will occur immediately. The body immune system recognizes these antigens, and will produce antibodies to destroy them.  The common causes include foods, and drugs (e.g. penicillin) insect venoms, penicillin, horse serum (used in some vaccines), occasionally immunotherapy (i.e. injection of allergen to which a person is allergic, in order to treat allergic diseases). The rare causes are towards pollens and other inhaled allergens. Some people have an anaphylactic reaction with no identifiable cause (Idiopathic). Certain allergens stimulate production of IgE antibodies which binds to mast cells and basophils. These cells are activated by binding of antigen to the IgE, which results in release of cytoplasmic granules from mast cells and basophils (e.g. histamine). Mast cell products increase vascular permeability and constrict bronchial smooth muscle. In some unfortunate individuals, it may cause circulatory collapse and death. The main treatment is administration of adrenaline (epinephrine).  Retrieved on Febuary 6, 2009 from Emergency Medical Secvices Agency, MET DST With references to: Lara. Hand & Jo. S, R. J. Mullins BY JESSLIN |
