Clinical and laboratory parameters trend in a patient with CLL developing HLH. Serum ferritin and temperature were significantly elevated from hospital admission to death. Although frozen plasma, red packed cells and platelet transfusions, the fibrinogen, hemoglobin and platelet count progressively dropped. Ferritin, serum ferritin in ng/mL; plt, platelet count, x10e3/mm³; fibrinogen, plasma fibrinogen mg/dL; Hb, hemoglobin in g/dL; and T, temperature in Celsius grade (°C).