Anaphylaxis and Insect Allergy

From Current Opinion in Allergy and Clinical Immunology
Jeffrey G. Demain; Ashley A. Minaei; James M. Tracy

Abstract

Anaphylaxis is an acute-onset and potentially life-threatening allergic reaction that can be caused by numerous allergic triggers including stinging insects. This review focuses on recent advances, natural history, risk factors and therapeutic considerations.

Recent findings Recent work suggests that concerns over insect allergy diagnosis continue to exist. This is especially true with individuals who have a convincing history of a serious lifethreatening anaphylactic event, but lack the necessary diagnostic criteria of venomspecific IgE by skin test or in-vitro diagnostic methods to confirm the diagnosis. The role of occult mastocytosis or increased basophile reactivity may play a role in this subset population. Additionally, epinephrine continues to be underutilized as the primary acute intervention for an anaphylactic reaction in the emergent setting.

Summary The incidence of anaphylaxis continues to rise across all demographic groups, especially those less than 20 years of age. Fortunately, the fatalities related to anaphylaxis appear to have decreased over the past decades. Our understanding of various triggers, associated risk factors, as well as an improved understanding and utilization of biological markers such as serum tryptase have improved. Our ability to treat insect anaphylaxis by venom immunotherapy is highly effective. Unfortunately, anaphylaxis continues to be underappreciated and undertreated especially in regard to insect sting anaphylaxis. This includes the appropriate use of injectable epinephrine as the primary acute management tool. These findings suggest that continued education of the general population, primary care healthcare providers and emergency departments is required.
Introduction

Anaphylaxis is an acute-onset, potentially fatal systemic allergic reaction.[1,2] Anaphylaxis can be triggered in numerous ways, but the three most common triggers are insect stings, foods, and medications.[3•,4–6] Manivannan et al. reviewed 208 patients and found that the inciting agents broke down into food (29.6%), medications (22.2%), insects (11.1%), others (7.4%), and unknown (29.6%). However, since large numbers of partially treated episodes often go undiagnosed or unrecognized, it is likely that anaphylaxis is under-reported. No one knows the true rates of anaphylaxis in general, although overall global trends indicate increasing rates in all age groups and populations.The increase is most significant in people living in good socioeconomic conditions and people under the age of 20. The largest number of anaphylaxis cases typically occurs in children and adolescents; however, fatalities from insect stings are more common in middle-aged and older adults.