Honeybee Venom Immunotherapy: A Comparative Study Using Purified and Nonpurified Aqueous Extracts in Patients with Normal Basal Serum Tryptase Concentrations

In this study, we compared a purified aqueous extract and the corresponding nonpurified aqueous preparation under the same build-up protocol in bee venom allergic patients with a normal baseline mast cell tryptase concentration. Eighty patients with a history of a systemic reaction were enrolled for immunotherapy using a 5-day rush protocol. Patients treated with the purified extract and those treated with the non purified aqueous extract who developed a systemic reaction underwent maintenance therapy with the purified aluminium hydroxide adsorbed preparations. Patients treated with the nonpurified aqueous extract who did not experience a systemic reaction during the rush phase underwent the maintenance phase with that extract. Systemic reactions during the build-up phase occurred significantly more often in patients treated with nonpurified aqueous extract than in those treated with the corresponding purified aqueous preparations. During the one-year maintenance phase, no systemic reactions occurred in either of the groups. Neither age nor baseline mast cell tryptase concentration presented a significant correlation with the occurrence of a systemic reaction during the treatment, while the type of extract did. In conclusion, nonpurified aqueous extracts induced more frequent systemic reactions than the purified aqueous preparations, during the same rush protocol. The efficacy seemed to be comparable.