Systemic reactions during maintenance immunotherapy with honey bee venom.

Immunotherapy with hymenoptera venoms is safe and effective in most patients but treatment failures have been reported. Five patients experienced systemic symptoms of anaphylaxis when they were in maintenance immunotherapy with honey bee venom. In one case, the patient presented a severe life-threatening reaction when stung by a honey bee. Three others had the development of new clinical sensitivity suggesting a re-sensitization. This occurred in the fifth patient after a severe viral infection. By means of a rush protocol and monthly doses of 200 to 400 micrograms of honey bee venom, the patients were subsequently protected efficiently. In most cases these reactions might have been predicted since patients experienced large local reactions prior to the systemic reactions when allergens were injected. Further, in four cases there was an increased skin test reactivity or raised serum honey bee venom IgE levels or both. In all patients, the levels of serum honey bee venom IgG was under 200 U/mL (IgG Pharmacia RAST).