What Is Myelofibrosis?
Myelofibrosis is a disorder characterized by a deficit in the stem cells of the bone marrow, which causes progressive replacement of normal bone marrow with useless fibrous tissue. This mainly impairs the marrow’s ability to manufacture red cells, but also occasionally impairs the manufacture of white cells and platelets. In some types of myelofibrosis, failure of marrow blood cell production is associated with blood production in the spleen, liver and lymph nodes, which causes these organs to enlarge. Myelofibrosis may develop gradually, usually in people over the age of 50 with no apparent cause; this is known as primary myelofibrosis.
Symptoms normally do not appear until several years after the onset of the disease. The most common initial symptomsfatigue, weakness and appetite lossare due to the anemia that results from insufficient red cell production. But eventually, other complications occur. The minimal survival time is estimated at four to five years after diagnosis of myelofibrosis, but many patients live up to 15 years. Treatment is aimed at relieving symptoms.
Secondary myelofibrosis is the term used when the disorder results from some other disease that damages the bone marrow. It may also occur if bone marrow is exposed to certain industrial toxins, viruses or to radiation.
What Causes Myelofibrosis?
- The cause of primary myelofibrosis is unknown.
- Secondary myelofibrosis arises as a result of some other disease that affects the bone marrow (such as metastatic cancer, Hodgkin’s disease, polycythemia vera, lymphoma, HIV infection, chronic myelogenous leukemia, multiple myeloma and acute leukemia), or from exposure to certain toxins (such as benzene) or to radiation, including x-rays.
Symptoms of Myelofibrosis
- Weakness and fatigue; heart palpitations; shortness of breath; paleness (pallor); loss of weight and appetite (due to anemia)
- Easy bleeding and bruising; clusters of pinpoint-size hemorrhages (petechiae) on the skin (due to platelet insufficiency).
- Fever and night sweats (due to overactive blood formation in the spleen and liver, or infection).
- Bone pain (in some cases)
- Attacks of gouty arthritis or kidney stones
- Abdominal pain, fullness, or breathing difficulty (due to enlargement of the spleen and liver)
- Frequent infections
- Feeling run down or tired
- There is no known way to prevent myelofibrosis, except in cases caused by exposure to radiation or industrial chemicals.
- Patient history and physical examination are necessary.
- Blood tests show abnormal numbers and appearance of blood cells.
- A bone marrow biopsy is necessary for a definite diagnosis.
How to Treat Myelofibrosis
- There is currently no effective treatment to cure or slow the progression of primary myelofibrosis.
- Cytoreductive therapy may be tried to reduce the number of cells in a lesion, usually a malignancy.
- Immunomodulatory drugs may be used.
- Blood transfusions may be administered, as needed, to treat anemia.
- Occasionally, treatment with recombinant human erythropoietin will combat anemia.
- Supplemental folic acid should be given to meet an increased need for this vitamin.
- The antigout drug allopurinol is prescribed when uric acid levels are elevated, to avoid kidney stones.
- Surgical removal of the spleen (splenectomy) may be indicated in cases where spleen enlargement causes severe problems for the patient, such as pain or difficulty eating.
- Bone marrow transplantation can be curative in patients under 45.
- Treatment of the underlying disease is essential for correction of secondary myelofibrosis.
When to Call a Doctor
- If you experience the symptoms of myelofibrosis, call a doctor.
Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference
Simeon Margolis, M.D., Ph.D., Medical Editor
Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50
Updated by Remedy Health Media