Ventricular fibrillation after a hymenoptera sting

A 54-year-old male, who had presented 2 ventricular fibrillation (VF) episodes with post-anoxic coma and later a return to consciousness and to a sinusal rhythm after defibrillation, have been placed a ventricular intracavitary stimulator (AICD). Since all the tests including the coronarygraphy have been found normal, we have paid attention to the anamnesis revealing an Apis mellifera sting before both VF episodes, previously considered irrelevant for the absence of relevant local symptoms. Intracutaneous tests were negative to Vespula sp. and positive to A. mellifera extract at a concentration of 0.01 μg/ml. Specific IgE for A. mellifera venom presented values of 2,36 U/ml for A. mellifera and < 0.35 U/ml per Vespula sp. and Polistes dominulus. The patient was then submitted to ITS with A. mellifera aqueous extract. During the RASH treatment no adverse reactions have been observed, whereas we witnessed a major adverse reaction, 3 min after the first 100 mcg maintenance dose, controlled with anti-H1 and cortisone reaction, nevertheless no reactions were observed during the 3 years the same dosage has been repeated monthly. Our case supports the hypothesis of an anaphylactic reaction as trigger of vasoconstriction in individuals affected by ventricular arrhythmia not explained with other causes such as a coronary disease, a myocardiopathy or a pharmacological toxicity. Arrhythmia can be a serious outbreak of a mediated IgE allergic reaction even without any relevant local symptoms. The diagnostics with lyophilized A. mellifera venom has been proven safe in a patient who suffered a cardiac anaphylaxis.