CD52 and viral encephalitis: Liba et al. described an 8-year old girl with anti-NMDA receptor encephalitis who had no response to sequential IVIg, plasma exchange and high-dose corticosteroids, rituximab, and cyclophosphamide treatment, but responded well to alemtuzumab, an anti-CD52 monoclonal antibody that affects memory B cells and T cells [15].