A case of anaphylaxis by ant (Ectomomyrmex spp.) venom and measurements of specific IgE and IgG subclasses.

Hypersensitivity to the stings of the Hymenoptera has been described since antiquity. The hypersensitive reactions to insect stings vary from minor skin reactions to severe and sometimes fatal anaphylaxis. Concerns about sting hypersensitivity have been increasing because of many incidents of allergic reactions of patients to the fire ant in the southern area of the United States as well as the harvester ant in some areas. We experienced one unique case with severe allergic reactions by ant of the Ectomomyrmex spp. of the subfamily Ponerinae, which is not a harvester ant. For three years the patient had been suffering from generalized allergic reactions such as anaphylaxis after the ant stings four-five attacks in a year. We determined that her reactions were due to specific IgE mediated type I hypersensitivity by the detection of a high level of specific IgE to the ant venom in her serum. The high level of specific IgG4 to the ant venom was also noted in her serum, however, the role of ant venom IgG4 was not clearly determined.