On day 7 following admission, she developed therapy refractory high fever (40°C), and high CRP (242 mg/dL) without elevated levels of PCT and negative microbiology, so CSS and a reactive HLH were suspected (calculation of HScore suggested 40%‐54% probability for HLH) despite missing hemophagocytosis in bone marrow aspiration. Here, CRP is linked to hemophagocytic syndrome.