IMMUNOLOGICAL REACTIVITY ON ONE-YEAR FOLLOW-UP OF SUBJECTS WITHOUT ALLERGY TO HYMENOPTERA STINGS

We studied Hymenoptera stings in 72 pest-control operators without any previous systemic reactions to Hymenoptera stings, and investigated t heir venom-specific IgE levels in serial specimens collected over one year. At the initial evaluation, venom-specific IgE was present in 25 (34.7%) of 72 pest-control operators, and venom-specific IgE titer sig nificantly decreased as the time interval from the last sting increase d (p < 0.001). in most cases, venom-specific IgE disappeared less than 3 years after the last sting. On the other hand, the ratio of subject s with positive CAP for venom-specific IgE was significantly increased with an elevation of total serum IgE level (p < 0.001). After the one year follow-up, venom-specific IgE titer in the 25 subjects with posi tive CAP decreased significantly (p = 0.026). Total serum IgE level mo dified the decline significantly (p = 0.011), but the time interval fr om the last sting did not. In elevated total IgE level (>250 IU/ml), t he decline of venom-specific IgE tended to be slow.