Hypocomplementemic urticarial vasculitis with angioedema, a rare presentation of systemic lupus erythematosus: rapid response to rituximab.

We report a case of hypocomplementemic urticarial vasculitis and recurrent angioedema in a patient with systemic lupus erythematosus unresponsive to mycophenolate mofetil, high-dose methylprednisolone, and intravenous immunoglobulin that responded rapidly to rituximab. Rituximab is a monoclonal antibody against CD20 transmembrane protein on the surface of mature and malignant B cells. No adverse effects occurred during or after therapy, and the patient was discharged from the hospital for outpatient rituximab infusion and follow-up care.