RESUMEN
In this study, 142 patients under 12 years of age with the diagnosis of urticaria accompanied or not by angioedema were examined. In all 72.6% of the patients were under 6 years of age. Boys and girls were equally affected, 13.4% of the cases had chronic urticaria, 56.3% had a previous history of urticaria, 88.0% had generalized urticaria, and about half of the cases had associated angioedema. The causes of the urticaria were identified or suspected in 32.4% of the cases. Drugs, foods, insect bites and stings, infections and cold were the most common or associated precipitating agents in that order. Histories revealed 27.5% of the cases had records of other allergic diseases, and 76.1% had allergic diseases in the family. Dermographisms were found in 16.2% of the cases, and 22.5% of cases had eosinophilia. The means of IgE levels in both acute and chronic urticaria were within normal limits, and there was no statistically significant difference between the two groups. Skin testing was of little practical value in evaluating the etiology of the urticaria. Clinical trials of drugs for symptomatic treatment revealed that clemastine, ketotifen and hydroxyzine gave approximately equally high response rates. All these three medications gave significantly greater response rates than chlorpheniramine.