Alerts and Notices
SynopsisPrimary myelofibrosis (PMF) is a rare myeloproliferative bone marrow disorder characterized by clonal myeloproliferation, variable degrees of fibrosis (identified with reticulin or trichrome stain), and abnormal megakaryocyte proliferation resulting in impaired hematopoiesis. It typically occurs in elderly patients (median age is 65 years), although PMF may occur at any age.
The peripheral blood smear often demonstrates leukoerythroblastic changes and teardrop-shaped red blood cells (RBCs), consistent with bone marrow fibrosis. As the marrow is replaced by fibrosis, the spleen will enlarge due to extramedullary hematopoiesis.
The bone marrow biopsy may be a "dry tap" due to extensive fibrosis and/or osteosclerosis replacing the marrow elements. Up to 60% of cases of myelofibrosis contain the JAK2 V617F mutation (which can be detected on peripheral blood or bone marrow).
Myelofibrosis is a chronic condition with many phases. When the disease is more progressed, there is a possibility it may transform into acute leukemia.
D75.81 – Myelofibrosis
52967002 – Myelofibrosis
Differential Diagnosis & Pitfalls
- Splenomegaly, pancytopenia, and CBC changes can occur with other hematologic disorders including leukemia and other myeloproliferative neoplasms; they can also occur due to nonmalignant or reactive causes (autoimmune disease or infection such as mononucleosis).
- Essential thrombocythemia, like PMF, is characterized by abnormal megakaryocytes (platelet-forming cells) and fibrosis.
- Some lymphomas can cause splenomegaly and bone marrow fibrosis. Careful examination of the peripheral blood and bone marrow as well as physical exam is critical for diagnosis.
Drug Reaction DataBelow is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.