Ultrarush venom desensitization after systemic reactions during conventional venom immunotherapy.

Background: Rush and ultrarush venom immunotherapy (VIT) protocols are safe and effective in patients with Hymenoptera hypersensitivity. However, these protocols have typically been used instead of conventional VIT and not in patients who have experienced adverse reactions during conventional VIT. To date, there are no reports of using an ultrarush VIT protocol to desensitize patients with a history of severe systemic reactions during conventional VIT.

Objective: To determine whether ultrarush VIT can be safely administered to a high-risk patient with a history of severe systemic reactions to conventional VIT.

Methods: Premedication with 40 mg of prednisone, 180 mg of fexofenadine, and 150 mg of ranitidine orally twice daily was initiated. The patient received VIT to mixed vespid and wasp in a medical intensive care unit via a 13-step buildup on day 1 followed by a 2-step buildup on day 2. Immunotherapy was begun with a dose of 0.005 microg of mixed vespid and 0.002 microg of wasp venom and achieved a total dose of 300 microg of mixed vespid and 100 microg of wasp venom.

Results: The patient tolerated the procedure with minimal adverse effects. She subsequently received maintenance dosing in the outpatient clinic weekly for 4 weeks and bimonthly for 8 weeks, and she continues monthly maintenance VIT.

Conclusions: We report the first successful use of ultrarush VIT in a high-risk patient with a history of severe systemic reactions during conventional VIT. This protocol should be considered in patients with a history of allergy to vespids or wasps who require VIT but cannot reach a maintenance dose with conventional VIT owing to systemic reactions.