Risk of anaphylaxis in patients with large local reactions to hymenoptera stings: a retrospective and prospective study

Background In the few studies available, the risk of developing systemic reactions (SR) to hymenoptera stings in patients with previous large local reactions (LLRs) to stings ranges from 0 to 7 %. We evaluated both retrospectively and prospectively the risk of SRs in patients with LLRs to stings.