S. Chegini

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.

Asthma and the diver

Self-contained underwater breathing apparatus (scuba) diving has grown in popularity, with nearly 9 million sport divers in the United States alone. Approximately 7% of the population has been diagnosed with asthma, which is similar to the percentage of divers admitting they have asthma. Numerous concerns exist regarding subjects with asthma who choose to participate in recreational diving. Among these concerns are pulmonary barotrauma, pneumomediastinum, pneumothorax, arterial gas embolism, ear barotrauma, sinus barotrauma, and dental barotrauma. Despite these concerns, a paucity of information exists linking asthma to increased risk of diving complications. However, it has long been the norm to discourage individuals with asthma from participating in recreational scuba diving. This article examines the currently available literature to allow for a more informed decision regarding the possible risks associated with diving and asthma. It examines the underlying physiological principles associated with diving, including Henry’s law and Boyle’s law, to provide a more intimate understanding on physiological changes occurring in the respiratory system under compressive stress. Finally, this article offers a framework for guiding the patient with asthma who is interested in scuba diving. Under the right circumstances, the patient with asthma can safely participate in recreational diving without apparent increased risk of an asthma-related event.