Chronic urticaria as a potential marker of systemic disease

Introduction . Chronic urticaria is a complex clinical and etiological problem, requiring a broad diagnostic panel in order to determine a possible connection with other diseases, particularly infectious ones.
Objective . To assess possible causes of chronic urticaria in patients hospitalized in the Department of Skin and Venereal Diseases of the Pomeranian Medical University.
Material and methods . The analysis comprised 104 patients (73 females and 31 males) aged 15 to 82 years. Diagnostic tests including the assessment of inflammatory parameters, indicators of gastrointestinal tract infections, thyroid diseases and connective tissue diseases were carried out. Tests for non-allergic physical urticaria as well as for IgE-dependent allergy were also performed. Results were statistically analysed using Statistica 7.0 software.
Results . The mean age of patients was 42.5 years. Females predominated in all age-related groups, constituting 70% of all examined patients. In 39.4% of patients no potential factor causing urticaria was found; then idiopathic urticaria was diagnosed. In 37.6% of examined patients only one possible cause of urticaria was indicated, whereas in the remaining 23% of patients more than one cause was established. Amidst the potential causes of chronic urticaria predominated chronic infections (34% of examined patients), mainly in the gastrointestinal tract. A connection with diseases of the thyroid gland, particularly of autoimmune aetiology, was also found (16.3%). Autoimmune urticaria was confirmed by positive autologous serum skin test in 24.3% of patients. Physical urticaria was diagnosed in 17.3% of patients and the coexistence of IgE-dependent allergy was confirmed in 15.4% of patients.
Conclusions . Chronic urticaria is found mainly in middle aged women. Most frequently chronic, indolent and subclinical infections coexisted with urticaria. In numerous patients coexistence of a few potential causes of urticaria was found.