The spleen in osteomyelofibrosis. A morphological and immunohistochemical study of 30 cases.

30 spleens from patients with biopsy proven primary osteomyelofibrosis were studied by histological and immunohistochemical methods. The presence of trilinear haematopoiesis along the splenic circulatory pathway supports the theory that the spleen acquires haematopoietic precursor cells by filtration of the peripheral blood. In addition, impairment of intrasplenic circulation with subsequent red pulp congestion, pulp cord fibrosis and haemophagocytosis is of importance for the pathogenesis of both marked splenic haematopoiesis and complications due to hypersplenism.