A 66-year-old man presents with a one-year history of pancytopenia, periodic
fevers, rigors, and the appearance of erythematous nonpruritic sloughing papules on
his arms and legs. He was admitted to the hospital because of the development of orthostatic
Physical examination revealed a temperature of 36.6°C, a pulse rate of 91 beats per minute, a blood pressure of 119/71 mmHg (75/48 while standing), and a respiratory rate of 16 breaths per minute. The examination was positive for pallor, marked edema of the legs and periorbital region, scattered mummular and erosive lesions with overlying eschars on both feet, both forearms, and right thigh and petechiae on the arms and chest.
Pertinent laboratory findings included pancytopenia and hyperferritinemia (12,620 ng/mL) with a normal serum iron, transferrin saturation, and diminished total iron-binding capacity. The results of a bone marrow biopsy and aspirate are shown in the panel below.
What is your diagnosis, what test(s) would you order to confirm your suspicions, and what treatment, if any, do you recommend?
Hematoxylin and esosin staining of a marrow biopsy (Panel A) and Giemsa staining of aspirate (Panels B, C) show numerous histiocytes with engulfed erythroid elements (Panel B) and mature erythrocytes (Panel C). Immunohistochemical staining for CD163 shows histiocytes filled with intracytoplamic erythrocytes. Dashed lines outline hemophagocytic histiocytes.
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