Background: No nationwide epidemiological survey of anaphylaxis in Japan has been conducted. The aim of this study was to elucidate the triggers and treatment of anaphylaxis in Japan.
Methods: We prospectively collected clinical information on the triggers and treatment of patients who developed anaphylaxis or were admitted to the emergency room with anaphylaxis in the training and teaching facilities of the Japanese Society of Allergology between February 2015 and October 2017.
Results: Seventy-nine of 451 facilities (18%) participated in the study, and a total of 767 patients (under 18 years, 73%; in-hospital, 7%) were enrolled. The most common triggers were food (68%), drugs (12%), food-dependent exercise-induced anaphylaxis (5%), insects (4%), and oral immunotherapy (3%), with drugs being the most common in-hospital trigger and food being the most common out-of-hospital trigger. The intramuscular injection of adrenaline in medical institutions accounted for 38% of cases, 10% of which required multiple doses. The rate of use of adrenaline self-injections in out-of-hospital cases was 12%.
Conclusion: The present study revealed the most common triggers and treatment for anaphylaxis in Japan. Self-management at the onset of anaphylaxis and adrenaline administration as the initial treatment may be insufficient. Therefore, it is necessary to thoroughly instruct patients and educate physicians regarding anaphylaxis.
Keywords: adrenaline; anaphylaxis; drug hypersensitivity; food hypersensitivity; insect allergy.