Bee allergy11/26/2023 ![]() It should therefore be performed only in specialist centres treating an adequate number of patients each year.Ĭan we predict the outcome of a future sting? Venom immunotherapy carries a risk (of about 10%) of inducing systemic allergic reactions and can produce anaphylaxis. This is because, although immunotherapy for hymenoptera venom is highly effective, the high incidence of spontaneous improvement, as well as the side effects of treatment, has to be taken into account. The indications in Britain for desensitisation are conservative (in some countries any patient with a generalised reaction, no matter how trivial, would be desensitised). Moderate systemic (angio-oedema, mild asthma, or lightheadedness etc)īefore desensitisation is given the nature of the sting must be accurately diagnosed and venom-specific IgE demonstrated. Severe systemic (cardiovascular and/or respiratory symptoms) Indications for venom immunotherapy Type of reaction Studies in the general population show that some subjects who have a history of stings but no reactions have venom-specific IgE. This means that if the history is not checked, and venom IgE to only a single venom is measured, the wrong diagnosis can result. Patients are rarely allergic to both bee and wasp venom. The term allergy refers to a state of clinical reactivity and is not the same as sensitisation (presence of specific IgE antibodies), which can occur without clinical reactivity. However, double positives can occur even with the radioallergosorbent test (in about 6% of cases). It is important to be aware that since the introduction of the more sensitive CAP-RAST, there have been more (up to 30%) false positive results-that is, patients with serum IgE to both bee and wasp venom (double positives) when they are allergic to only one venom. Alternatively, serum bee-specific and wasp-specific IgE can be measured by a radioallergosorbent test (RAST), CAP-RAST, or other assays. Skin tests-either skin prick tests or intradermal tests with bee and wasp venom and the appropriate positive and negative controls-are more accurate but should be done by allergists as skin tests for venom are more difficult to interpret than skin tests for inhaled allergens. ![]() The history should be confirmed by demonstrating, by skin test or blood test, specific IgE this is essential if desensitisation is considered as a treatment. Reasons for the variable outcome are not well understood but include the interval from the last sting (the longer the interval the lower the risk of another generalised reaction), the patient’s immune response at the time of the sting (this will change with time), the dose of venom injected, and the site of the sting
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