Background. Anaphylaxis is the most severe form of acute systemic allergic reactions. Several recommendations have been proposed to guide and standardize anaphylaxis approach and management. The objective of this study is to characterize a cohort of patients referred through an anaphylaxis fast-track system, to enhance and standardize anaphylaxis patient care. Methods. Observational study including patients with anaphylaxis admitted in the emergency department (ED) and/or referred through the fast-track system (June 2022 - June 2025). Collected data included demographics, clinical presentation, aetiology, treatment, adrenaline autoinjector (AAI) prescription, request for serum tryptase testing, biphasic reactions, diagnosis and follow-up care. Results. Over the 399 patients referred through the fast-track system for specialist evaluation, anaphylaxis was confirmed in 120 patients. Drug-induced anaphylaxis was the most prevalent, with nonsteroidal anti-inflammatory drugs the most reported (46.3%). Food-induced anaphylaxis was the second cause, with shellfish accounting for most cases (63.5%). The most common association of symptoms was mucocutaneous and respiratory symptoms (49.5%). Among the 120 confirmed cases, intramuscular adrenaline was administered in 68.4% (67/98) of patients admitted to ED and AAI in only 18.4% (18/98). Biphasic reactions were only reported in three patients. No fatalities or recurrent episodes were documented. Conclusions. These findings highlight the importance of standardized protocols or fast-track systems for anaphylaxis diagnosis and management, allowing for a rapid recognition, treatment and management of patients. Nevertheless, the need to continually improve medical education and training remains. This study is limited by its selected cohort, the exclusion of primary-care emergency department data owing to coding limitations, and its inherently descriptive design.
Ferreira et al. (2026) studied this question.