Rituximab in Refractory Chronic Spontaneous Urticaria: An Encouraging Therapeutic Approach

<b><i>Background:</i></b> Chronic spontaneous urticaria (CSU) is a frequent mast cell-driven disease that affects approximately 0.5–1% of the population. Antihistamines are currently the drugs of choice in patients with CSU. Omalizumab has been shown to be very effective in CSU and has been recently approved as second-line therapy. However, although its introduction has markedly improved the therapeutic possibilities for CSU, there is still a hard core of patients who do not respond and require effective treatment. <b><i>Methods:</i></b> We report the case of a patient who achieved an 8-month remission of refractory CSU following the use of rituximab, and perform a review of the literature regarding the use of rituximab in CSU. <b><i>Results:</i></b> There was a remarkable improvement in her CSU after the administration of rituximab maintained over time. <b><i>Conclusion:</i></b> Rituximab is a chimeric murine/human monoclonal antibody directed against CD20, which depletes memory B-lymphocytes that are necessary for autoantibody production. The abrogation of the autoantibody production is the proposed mechanism by which it may alleviate the symptoms of CSU.