Honey Bee Venom Re-Challenge During Specific Immunotherapy: Prolonged Cardio-Pulmonary Resuscitation Allowed Survival in a Case of Near Fatal Anaphylaxis

BACKGROUND Specific immunotherapy for patients with honey bee hypersensitivity is commonly applied. Re-challenge with venom is performed to prove protection.CASE PRESENATION We report a case of near fatal anaphylaxis with asystolia for 24 minutes in a 35-years-old patient with mastocytosis after honey bee sting challenge despite 5-years of specific immunotherapy. Successful cardio-pulmonary resuscitation (CPR) was applied for 32 minutes.CONCLUSION This intervention demonstrates, that in anaphylaxis with cardio-vascular arrest prolonged CPR for up to 40 minutes might be appropriate to overcome half time span of massively released histamine. Failure of specific immunotherapy was possibly due to sensitization to the allergen Api m10, probably underrepresented in commercial honey bee venom extracts. Also, molecular analyses might alert to potential unsuccessful outcome of venom specific immunotherapy especially in high-risk patients such as mastocytosis.

Hymenoptera Venom Immunotherapy: Immune Mechanisms of Induced Protection and Tolerance

Hymenoptera venom allergy is one of the most severe allergic diseases, with a considerable prevalence of anaphylactic reaction, making it potentially lethal. In this review, we provide an overview of the current knowledge and recent findings in understanding induced immune mechanisms during different phases of venom immunotherapy. We focus on protection mechanisms that occur early, during the build-up phase, and on the immune tolerance, which occurs later, during and after Hymenoptera venom immunotherapy. The short-term protection seems to be established by the early desensitization of mast cells and basophils, which plays a crucial role in preventing anaphylaxis during the build-up phase of treatment. The early generation of blocking IgG antibodies seems to be one of the main reasons for the lower activation of effector cells. Long-term tolerance is reached after at least three years of venom immunotherapy. A decrease in basophil responsiveness correlates with tolerated sting challenge. Furthermore, the persistent decline in IgE levels and, by monitoring the cytokine profiles, a shift from a Th2 to Th1 immune response, can be observed. In addition, the generation of regulatory T and B cells has proven to be essential for inducing allergen tolerance. Most studies on the mechanisms and effectiveness data have been obtained during venom immunotherapy (VIT). Despite the high success rate of VIT, allergen tolerance may not persist for a prolonged time. There is not much known about immune mechanisms that assure long-term tolerance post-therapy.