Pathogenetic aspects of chronic urticaria. Retrospective and prospective analysis of the patients of the Department of Dermatology, Poznan University of Medical Sciences

Introduction
Urticaria is a disease with a complex pathomechanism. Confirmation of the cause in chronic urticaria seems to be a great challenge for specialists.
Aim: To assess the frequency of different types of urticaria and their coexistence in 1 patient, diseases associated with chronic urticaria and the frequency of accompanying oedema.

Material and methods
The study was divided into two parts. Retrospective analysis included 441 chronic urticaria patients at the age of 15 or older hospitalized in 10 years. Information from history of the disease has been placed in a specially designed form. For the prospective analysis 78 patients have been chosen out of 441 subjects previously qualified for retrospective analysis.

Results
The most common type of urticaria was autoimmune (27.9% R; 30.8% P), spontaneous (19.3% R; 39.7% P) and aspirin-induced urticaria (17.5% R; 25.6% P). The most common coexisting types of urticaria were autoimmune with aspirin-induced (7.5% R; 10.3% P) and autoimmune with dermographic urticaria (3.2% R; 5.1% P). In more than half of the patients (66.7%) one type occurs only. Angioedema coexisted in over half of the patients (58% R; 69.2% P) Among the coexisting comorbidities in people with accompanying angioedema, statistically significant differences appeared in patients with thyroid diseases (19.9% with oedema and 4.9% without oedema). Among drug users, there was a greater difference between the percentage of patients with or without angioedema than among non-drug users.

Conclusions
It was found that among the inducing factors – pressure and stress and among drugs taken for diseases other than urticaria – NSAIDs had an influence on the persistence of symptoms in P patients.