Findings during the prefibrotic stage:
(1) moderate or marked splenomegaly
(2) moderate or marked hepatomegaly
(3) moderate to marked anemia
(4) white blood cell count variable (decreased, normal or elevated)
(5) platelet count variable (decreased, normal or elevated)
(6) leukoerythroblastosis present
(7) moderate to marked poikilocytosis in RBCs
(8) moderate to marked dacryocytes (tear-drop shaped RBCs)
(9) hypercellular bone marrow
(10) megakaryocytic proliferation with atypia
(11) myeloid series proliferation
(12) collagen and/or reticulin fibrosis
(13) dilated marrow sinuses with intraluminal hematopoiesis
(14) osteosclerosis (new bone formation)
where:
• Atypical changes in megakaryocytes include megakaryocyte clusters, bare nuclei, abnormal nuclear lobulations.
