Clinical features of acute anaphylaxis in patients admitted to a university hospital: an 11-year retrospective review (1985-1996)

Background: Although anaphylaxis is considered a life-threatening event, there is a lack of information on the clinical characteristics at presentation, both in adults and in children. Objective: To describe in a nonselected population the clinical characteristics and the treatments of acute anaphylaxis triggered by different agents. Methods: This is a retrospective review of the clinical features of 113 episodes of acute anaphylaxis resulting in admission to a university hospital. Initially, the 107 patients visited the emergency room and were then admitted to the hospital. Results: Most anaphylactic events (63%) occurred at home. The most frequent symptoms involved the respiratory system (78%) and the skin (90%). Drugs, especially nonsteroidal anti-inflammatory drugs and antibiotics, were the most frequent cause of anaphylaxis in adults (49%). Patients with drug-induced anaphylaxis were older and more often had cardiovascular symptoms (hypotension and tachycardia) (P = 0.0064). Hymenoptera venom was the second most frequent cause of anaphylaxis (29%). Most of the patients with hymenoptera venom anaphylaxis were male (80%) and more frequently they had no history of atopy (P = 0.012). In food-induced anaphylaxis, the cardiovascular system was less likely to be involved (P < 0.05) (39%). Seafood seems to be frequently involved in food-induced anaphylaxis in our area. Specific immunotherapy-induced anaphylaxis occurred more often in younger patients (P = 0.032). Epinephrine seems to be underused in Italy (only 15% of patients received it), especially for respiratory symptoms. Conclusions: Anaphylaxis triggered by different agents may have different clinical presentations and may occur in different types of patients. In Italy, the inadequate use of epinephrine for anaphylaxis treatment needs to be publicized to both physicians and the general population.