Table 5 Distinguishing features of primary myelofibrosis and autoimmune myelofibrosis
From: Fibrosis and bone marrow: understanding causation and pathobiology
Features | PMF | AIMF |
|---|---|---|
I. Bone marrow | ||
 Megakaryocytes | Proliferation and atypia | Lack of clustering/atypia |
 Myeloid/erythroid dysplasia | Present | Absent |
 Basophilia or eosinophilia | Present/ absent | Absent |
 Lymphocytic infiltration | Absent | Present |
 Osteosclerosis + /– – | May be present | Absent |
II. Laboratory features | ||
 Anemia |  + /– |  + /– |
 Leukocytosis | Usually +  + /– | Absent |
 Elevated LDH | Usually +  +  |  ±  |
 Autoantibodies |  + /– |  +  |
III. Clinical features | ||
 Constitutional symptoms | Common | Uncommon |
 Splenomegaly | Common | Absent/mild |
IV. Other laboratory features |  |  |
 Leukoerythroblastosis |  +  +  |  + /– |
 JAK2, CALR, or MPL mutation  |  + (90% of cases) | – |