Histiocytic Medullary Reticulosis

Abstract

A 70-year-old man with a diagnosis of histiocytic medullary reticulosis had a severe anemia accompanied by reticulocytosis, erythroid hyperplasia of the marrow, shortened red blood survival, accelerated clearance of plasma Fe and an expanded total marrow space. The findings are characteristic of hemolytic anemia. Destruction of erythrocytes by marrow histiocytes may cause the anemia. Extensive erythrophagocytosis by histiocytes was evident on examination of each of 3 aspirates of marrow. There were substantial amounts of Fe within the histiocytes. The histiocytes could not incorporate Fe bound to transferrin. There was normal incorporation of plasma Fe into hemoglobin but a subsequent progressive diminution of red blood cell radioactivity during a period in which no radioiron was lost from the body. The radioactivity following erythrocyte destruction appeared in sites of active marrow. The Fe which probably accumulated in the histiocytes by erythrophagocytosis could not be reutilized for hemoglobin synthesis. The value for the serum Fe was low despite the large amount of histiocytic Fe indicating unavailability of histiocytic Fe for metabolic needs.