Current challenges and controversies in the management of chronic spontaneous urticaria.

Chronic spontaneous urticaria (CSU) is characterized by the recurrence of itchy wheals for at least 6 weeks, affects up to 1% of the general population and may severely impair quality of life. H1-antihistamines are the cornerstones of treatment, but in about 10% of cases they fail to control the disease even at higher than licensed doses. In these patients, short courses of oral steroids may induce a remission in about 50% of cases. Omalizumab, a monoclonal anti-IgE, is effective in antihistamine-unresponsive patients although optimal treatment duration needs to be defined. Immunosuppressive treatment with cyclosporine is also effective in the majority of antihistamine-resistant chronic spontaneous urticaria (CSU) patients, but its use is limited by potential side effects. In refractory patients, other approaches include intravenous immunoglobulin, rituximab, dapsone and anticoagulants. The present review looks with particular interest at the prevalence of treatment failures with the main third-level treatments (corticosteroids, omalizumab and cyclosporine) and discusses them in light of the possible different pathogenic mechanisms underlying chronic spontaneous urticaria.