IL2 and hemophagocytic syndrome: She was then re-admitted to the hospital with urosepsis, and new demyelinating lesions were found (Figures 1G–I); persistently elevated ferritin, C-reactive protein (CRP), and interleukin-2 (IL-2) receptor levels raised concerns of hemophagocytic lymphohistiocytosis (HLH) with CNS involvement, as well as possible macrophage activation syndrome (MAS), consequently, treatment with anakinra and cyclosporine was initiated.