Diagnostic profile among patients with chronicurticaria/angioedema attending a reference clinic in Brazil: the role of auto-immunity.

Methods Two hundred and fifty four patients aged 13-80 years (202 females,79.5%), with chronic urticaria/angioedema who receive care at the Allergy Clinic of the Clinical Hospital of Ribeirao Preto Medical School in Brazil, were evaluated prospectively. Patients were inquired about triggering of symptoms by medications and/or physical agents and presence of anaphylaxis. In addition, they were investigated by skin testing and tests for eosinophilia, IgE, and hepatitis B and C. Autoimmune basis was characterized by presence of positive autologous test, anti-thyroid or antinuclear antibodies (ANA). When indicated, a skin biopsy was performed. Use of medications for urticaria was analyzed.