Serum interleukin-18 and immunoglobulin E in chronic spontaneous urticaria and their relation to severity of the disease

Background Interleukin-18 (IL-18) is a proinflammatory cytokine that can induce either T helper 1 response or T helper 2 response. It may play an important role in either chronic inflammatory, autoimmune, or allergic diseases, but its role in chronic urticaria is still unclear. Immunoglobulin E (IgE) plays an essential role in type I hypersensitivity reaction. Objective To assess serum levels of IL-18 and IgE in patients with chronic spontaneous urticaria (CSU) and their possible association with the clinical severity of the disease. Patients and methods A total of 30 patients with CSU were selected for this case–control study, in addition to 15 age-matched and sex-matched healthy individuals as controls. The severity of urticaria was assessed using urticaria activity score 7. Serum levels of IL-18 were measured using the ELISA technique. Serum IgE levels were measured using the electrochemiluminescence immunoassay technique. Results The mean serum level of IL-18 was significantly higher in patients with CSU (214.9±167.3 pg/ml) than in controls (115.6±121.1 pg/ml). Moreover, the mean serum level of IgE was significantly higher in patients with CSU (412.8±533.9 IU/ml) than in controls (74.67±55.73 IU/ml). A statistically significant correlation between clinical severity of urticaria and the serum level of either IL-18 or IgE was found. Conclusion IL-18 and IgE are involved in the pathogenesis of CSU and could be good and reliable markers for the evaluation of disease severity. Targeting IL-18 could be a novel treatment approach for patients with CSU.