The World Allergy Organization (WAO) Guidelines for the assessment and management of anaphylaxis provide a unique global perspective on this increasingly common, potentially life-threatening disease. Recommendations made in the original WAO Anaphylaxis Guidelines remain clinically valid and relevant, and are a widely accessed and frequently cited resource. In this 2015 update of the evidence supporting recommendations in the Guidelines, new information based on anaphylaxis publications from January 2014 through mid- 2015 is summarized. Advances in epidemiology, diagnosis, and management in healthcare and community settings are highlighted. Additionally, new information about patient factors that increase the risk of severe and/or fatal anaphylaxis and patient co-factors that amplify anaphylactic episodes is presented and new information about anaphylaxis triggers and confirmation of triggers to facilitate specific trigger avoidance and immunomodulation is reviewed. The update includes tables summarizing important advances in anaphylaxis research.

Controversies exist with regards to in vivo approaches to delayed immunologically mediated adverse drug reactions (ADR) such as exanthem (maculopapular eruption), drug reaction with eosinophilia and systemic symptoms (DRESS), acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson syndrome/toxic epidermal necrolysis, and fixed drug eruption. In particular, widespread differences exist between regions and practice on the availability and use of intradermal testing (IDT) and patch testing, the standard drug concentrations used, the use of additional drugs in IDT and patch testing to help determine cross-reactivity, the timing of testing in relation to the occurrence of the adverse drug reaction, the use of testing in specific phenotypes, and the use of oral challenge in conjunction with delayed intradermal and patch testing to ascertain drug tolerance. It was noted that there have been advances in the science of delayed T-cell mediated reactions that have shed light on immunopathogenesis and provided a mechanism of pre-prescription screening in the case of HLA-B*57:01 and abacavir hypersensitivity and HLA-B*15:02 and carbamazepine SJS/TEN in Southeast Asians. Future directions should include the collaboration of large international networks to develop and standardize in vivo diagnostic approaches such as skin testing and patch testing combined with ex vivo and in vitro laboratory approaches.