Probable causes of chronic urticaria among patients hospitalized in the Department of Dermatology, University of Medical Sciences in Poznań between 1997-2003

Chronic urticaria is a heterogenous disease characterized by urticarial wheals which appear and disappear without leaving a trace. In case of angioneurotic oedema (oedema Quincke) the process is localized in deeper part of subcutaneous tissue. Based on the duration of urticarial process the disease may be classified as acute (episodes up to 6 weeks) and chronic (episodes over 6 weeks). Etiological classification of urticaria consists of immunologic, non-immunologic, sympthomatic and idiopathic types of the disease.
A group of 332 chronic urticaria patients hospitalized in the Department of Dermatology in Poznań between 1997-2003 was analyzed. The age of the patients ranged from 2 years to 76 years. In the analyzed group 67% were female and 33% were male patients. According to anamnesis and results of diagnostic procedures, the most probable cause of the disease was established in 53% of the patients. Latent foci of infection were found in 38,2%. Hypersensitivity to ASA and it’s derivatives was recorded in 25% and 6,8% of the patients were hypersensitive to penicillin. A positive ASST was found in case of 25 patients out of 95 (26,5%), suggesting autoimmunological cause of chronic urticaria. In 3,6 % of patients physical urticarias were diagnosed.
In 34,7% of the patients, more than one etiological factor was discovered. In 12,3% of all patients, it was not possible to find a causative factor of the disease.
Our study emphasizes the complexity of etiopathological factors and indicates the possibility of multiple factors co-existance. Therefore in clinical practice diagnostic process of chronic urticaria may be extremely difficult and long lasting.