Teenager Suffered from Idiopathic Anaphylaxis and Chronic Spontaneous Urticaria Successfully Treated with Omalizumab: A Case Report

Anaphylaxis is a serious and probably lethal systemic reaction. When a trigger cannot be determined, idiopathic anaphylaxis is considered. It can occur as a complication of chronic spontaneous urticaria (CSU). In idiopathic anaphylaxis presenting with frequent attacks, long-term prophylaxis with H1antihistamines and steroid treatment is recommended but rarely effective. Omalizumab, a humanized monoclonal antibody drug that decreases free immunoglobulin E molecules in the circulation, is approved for the treatment of chronic severe persistent allergic asthma and CSU. We report a 15-year-old female patient suffering from CSU concomitant with idiopathic anaphylaxis. Omalizumab at a dose of 300 mg once every 4 weeks was administered for 6 months. The patient has remained asymptomatic during therapy and 3 months after the end of the therapy.