Allergy to bumblebee venom. I. Occupational anaphylaxis to bumblebee venom: diagnosis and treatment.

We describe six patients with severe occasional anaphylaxis, caused by stings of bumblebees. Sensitization to bumblebee venom was confirmed by intracutaneous tests and RAST with purified bumblebee venom. Three patients changed their occupation and will probably not be stung by bumblebees in the future. The other patients started immunotherapy with newly purified bumblebee venom extract. After 1 year of treatment, no severe side-effects had occurred and clinical benefit in two patients could be demonstrated, as both skin sensitivity or serum IgE to bumblebee venom had decreased. Moreover, both patients were unresponsive to in-hospital sting challenge.