Global trends in anaphylaxis epidemiology and clinical implications

The true global scale of anaphylaxis remains elusive, because many episodes occur in the community without presentation to healthcare facilities, and most regions have not yet developed reliable systems with which to monitor severe allergic events. The most robust datasets currently available are based largely on hospital admissions, which are limited by inherent issues of misdiagnosis, misclassification and generalizability. Despite this, there is convincing evidence of a global increase in rates of all cause-anaphylaxis, driven largely by medication and food-related anaphylaxis. There is no evidence of parallel increases in global all-cause anaphylaxis mortality, with surprisingly similar estimates for case fatality rates at approximately 0.5-1% rate of fatal outcomes for hospitalizations due to anaphylaxis across several regions. Studying regional patterns of anaphylaxis to certain triggers have provided valuable insights into susceptibility and sensitizing events: for example, the link between the monoclonal antibody cetuximab and allergy to mammalian meat. Likewise, data from published fatality registers can identify potentially modifiable risk factors which can be used to inform clinical practice, such as prevention of delayed epinephrine administration, correct posturing during anaphylaxis, special attention to populations at risk (such as the elderly on multiple medications) and use of venom immunotherapy in individuals at risk of insect-related anaphylaxis