The mainstay of treatment for HLH has been described as steroids, and recently, other immunosuppressive therapies such as anakinra (an IL-1 blocker), ruxolitinib (JAK1/2 inhibitor), alemtuzumab (CD52 monoclonal antibody), and emapalumab (anti-IFN-γ monoclonal antibody) have been reported with some success. The gene discussed is CD52; the disease is hemophagocytic syndrome.