Allergy to bumblebee venom. III. Immunotherapy follow-up study (safety andefficacy) in patients with occupational bumblebee-venom anaphylaxis

Background: The objective was to investigate whether venom immunotherapy wi th bumblebee venom (BBV) is safe and effective. Methods: Eleven patients with severe occupational anaphylaxis caused by sti ngs of bumblebees were studied. Sensitization to bumblebee venom was confir med by skin tests and RAST. Immunotherapy was started with bumblebee venom extract by the semirush procedure, because these patients showed a primary sensitization to Bombus venom, and a low or absent degree of cross-reactivi ty with honeybee venom. IgE titer and skin tests with bumblebee venom were performed yearly. Efficacy was evaluated by means of in-hospital sting chal lenge and/or occupational field stings from bumblebees. Results: All patients reached maintenance dose in 6 weeks without severe si de-effects. During the follow-up period (1.5-5 years), three systemic react ions in two patients were seen in 20 bumblebee stings. However, these react ions were milder than the index sting. Conclusions: Immunotherapy with bumblebee venom is safe and effective, and is comparable with honeybee and yellow-jacket venom immunotherapy.