Natural course of physical and chronic urticaria and angioedema in 220 patients.

BACKGROUND Information about spontaneous remission of chronic urticaria is limited. OBJECTIVE To investigate the natural course of urticaria, we followed up 220 adults in a prospective study. METHODS Patients were followed up for 1 to 3 years to evaluate interventions, to detect latent causes, and to study the natural course of urticaria. The diagnosis was made by detailed history-taking as well as laboratory and provocation tests. RESULTS Thirty-five percent of all patients were free of symptoms after 1 year. In 28.9% of patients, symptoms had decreased. Spontaneous remission occurred in 47.4% of the patients in whom no cause of their urticaria and/or angioedema could be identified and in only 16.4% of the patients with physical urticaria. A cause could be identified in 53.1% of the patients. Thirty-six percent of the patients had idiopathic urticaria. Chronic idiopathic urticaria combined with physical urticaria occurred in 10.9%. CONCLUSION In general, the prognosis for spontaneous remission is reasonable, with the exception of the subgroup (33.2%) with physical urticaria.