Sensitization following Hymenoptera whole body extract therapy.

Treatment of an insect-sensitive patient with Hymenoptera whole body extracts (WBE) led, on five occasions, to a serum sickness--like syndrome which did not recur after therapy was stopped. The patient was found to be sensitive by skin test, histamine release, and radioallergosorbent test (RAST) to both venom and WBE as well as to venomless bee body preparations. Subsequent therapy with honeybee and yellow jacket venoms was without sequelae, and after treatment the patient did not react to a sting. In order to assess the frequency of sensitivity to irrelevant body proteins in patients treated with WBE we carried out WBE RASTs on sera from 15 such patients and compared them with those from 15 nontreated insect-allergic patients who had similar venom-specific IgE antibody levels. None of the patients allergic to insects who had not been treated with WBE had detectable IgE anti-WBE antibodies, while about 50% of those treated with WBE had developed IgE antibodies against these proteins. It appears that sensitization to nonvenom WBE proteins in terms of the development of IgE antibody is a common result of this therapy, and, rarely, repeated challenge with this complex antigenic mixture can also lead to clinical illness.