Acute urticaria presenting in the emergency room of a general hospital

BACKGROUND: Acute urticaria is a common disorder that often prompts patients to seek treatment in the emergency room (ER). There are few data on acute urticaria presenting in ER.OBJECTIVES: This study aimed to provide demographic and clinical data of patients presenting with acute urticaria at an ER of an Italian general hospital covering an area of about 90,000 inhabitants. The predictive factors of the length of stay in the ER had also been investigated.METHODS: The database of ER patients was searched for urticaria by ICD-9 code and by keywords in the diagnosis description. All the medical records of the identified patients were reviewed and the length of stay in ER was noted.RESULTS: A total of 459 patients were admitted to ER with acute urticaria in a 1-year period corresponding to 1.01% of total ER visits and to 1.2 admission per day. Angioedema was present in 139 cases (30.3%), fever in 55 (12%). Twenty-nine patients fulfilled the criteria of anaphylaxis. Triggers could be identified in 193 cases (42%): drugs in 20.7%, insects bites (10.2%), foods (7.4%) and contact urticaria in 3.7%. Anaphylaxis (p<0.001), food (p<0.05) and drugs (p<0.05) as triggers were significant and independent predictive factors of the length of stay in ER.CONCLUSIONS: Patients with acute urticaria are frequently referred to the emergency room, but only in a few cases urticaria is associated with severe allergic manifestations. Drug and food hypersensitivity, together with anaphylaxis, are the best predictors of the length of stay in ER.