Anaphylaxis in an adult population: A clinical audit of practice in a large Australian tertiary referral hospital

Abstract

Anaphylaxis remains a difficult entity to diagnose and manage, typically requiring acute medical intervention and close follow up to confirm the diagnosis and provide a plan for future management. In this study, the diagnostic outcomes of patients referred to a tertiary adult clinical immunology unit for the assessment of anaphylaxis were reviewed. Methods: A retrospective review was undertaken of patients referred for the assessment of anaphylaxis to the Immunology and Allergy unit at John Hunter Hospital NSW.The study reviewed all patients referred between 1st of July 2011 and 31st of December 2012. 120 patients were included in the analysis. Results: A diagnosis of anaphylaxis was confirmed in 52 patients (43%), and the diagnosis was largely excluded in 54 patients (45%).The diagnosis remained unclear in 14 patients (12%). Of those confirmed to have anaphylaxis, the triggers included medications (38%), foods (27%), insect stings (13%), food associated exercise induced anaphylaxis (8%), idiopathic (8%) and mast cell instability (3%). Chronic urticaria, vocal cord dysfunction, panic disorder, large local reactions, angiotensin converting enzyme inhibitor - associated angioedema and poorly controlled asthma were identified as important causes of diagnostic confusion in those patients identified not to have anaphylaxis. Conclusion: An allergist review of patients suspected of having anaphylaxis is an important part of patient management. An alternative diagnosis was made and management strategy redirected in almost half the patients.There is a clear need for both ongoing education to improve anaphylaxis management, as well as education around those diseases that may mimic this life threatening condition.