The aim of this study was to assess the prevalence, clinical patterns and treatment of asthma in a well-defined area near the North East Italian border (Province of Trieste, 212 kmq, 30,000 inhabitants aged 0-15 years), served by only one children's hospital. The study was carried out from January to December 1991, in the Emergency Department (ED). 118 patients aged from 3 months to 16 years (mean age 5 years) presented bronchial asthma (0.7% of total ED consultation, 6.2% of acute respiratory tract disease). 29 (24.6%) were first diagnosis, 89 (75.4%) were formerly diagnosed. 57% of patients came to the ED in autumn and winter, 36% in spring and 7% in summer; 19.5% of patients came to the ED during the night. Main presentation symptoms were cough (66%), dyspnea (46%), fever (24%). Treatment consisted of aerosolized salbutamol (50%), associated with oral corticosteroids (31%), iv corticosteroids (3%), aerosolized beclomethasone (10%); 6% of patients received only oral salbutamol. 21 patients were hospitalized, all but one in the ED. In all cases hospitalization lasted less than 2 days and therapy was similar to that of non hospitalized patients, except for administration of aminophylline and iv corticosteroid in 5% of patients. ED consultation and hospitalization for bronchial asthma are low in our area, probably due to good working of the Allergologic Centre and to good connection of this structure with paediatricians.