Anaphylaxis: a decade of a nationwide allergy society registry.

Background and objective Anaphylaxis is an acute, life-threatening, multi-organ hypersensitivity reaction. Objective: The aim of this study was to identify the causes of anaphylaxis in Portugal, contributing to a better knowledge of the anaphylaxis epidemiology and management. Methods During a 10-year period a nationwide notification system for anaphylaxis was implemented, with voluntary reporting by allergists. Data on 1783 patients with anaphylaxis were included. Detailed characterization of etiopathogenesis, manifestations and clinical management was obtainedfrom pediatric and adult ages. Results The mean age was 32.7±20.3 years, 30% under 18 years of age; 58% were female. The mean age at the first anaphylaxis episode was 27.5±20.4 years (ranging from 1-month-old to 88years). The main culprits of anaphylaxis were foods (48%), drugs (37%) (main trigger in adults, 48%) and hymenoptera-venoms (7%). The main culprit foods were shellfish (27%), fresh fruits (17%), cow's milk (16%), treenuts (15%), fish (8%), egg (7%) and peanut (7%). The main drugs were nonsteroidal anti-inflammatory drugs(43%), antibiotics (39%) and anaesthetic agents (6%). Other causes were exercise (3%), latex (2%), cold-induced (2%) and idiopathic anaphylaxis (2%). Most patients (80%) were admitted to the emergency department; only 43% received adrenaline treatment. Recurrence of anaphylaxis occurred in 41% of patients (21% with ≥3 anaphylactic episodes); 7% used an adrenaline autoinjector device. Conclusions Food has been the leading cause of anaphylaxis in Portugal, while drugs were the main elicitors in adults. We highlight the undertreatment with adrenaline and recurrent episodes, pointing for the need to improve diagnostic and therapeutic approaches of anaphylaxis.