Myelofibrosis

Alternative names: Myeloid metaplasia.

Myelofibrosis is a rare disease in which bone marrow is gradually replaced by fibrous scar tissue.  As a result, the marrow is unable to produce sufficient new blood cells, resulting in anemia, bleeding problems, and a higher risk of infection.

Incidence; Causes and Development; Contributing Risk Factors

Myelofibrosis usually develops gradually and in people aged over 50, with those aged 60-70 being most likely to develop the condition.  Men are slightly more likely than women to develop it.  Exposure to petrochemicals such as benzene and toluene, and intense radiation may increase the risk of developing the condition.

There is no known cause.  However, bone marrow scarring caused by leukemia or lymphoma is called secondary myelofibrosis.

There are no known risk factors for myelofibrosis.

Signs and Symptoms

The liver and spleen will try to compensate by taking over some of the blood cell production, causing swelling of these organs, which can in turn result in a feeling of abdominal fullness.

Bone pain, difficulty breathing, abnormal/easy bleeding, easy bruising, fatigue, general malaise, weight loss, fever, night sweats, becoming pale (anemia), are also symptoms of myelofibrosis.

Diagnosis and Tests

A complete blood count, blood smear, bone marrow biopsy, and genetic testing are the methods generally used to confirm a diagnosis and rule out other causes of the symptoms.

Treatment and Prevention

Bone marrow or stem cell transplants can help young people who have the disease, and may even cure it.  Other possible treatments include blood transfusions, anemia medications, radiation and chemotherapy, or splenectomy (if swelling becomes severe, or to reduce anemia.)

Hydroxyurea may control complications such as enlargement of the liver and spleen, reduce the number of white cells and platelets in the blood, and improve anemia.

Thalidomide and lenalidomide is used to reduce symptoms and treat anemia.

Prognosis; Complications

Symptoms generally worsen over time, and the average survival period is about 5 years, but some people can survive much longer.

Myelofibrosis increases the risk of getting an infection, and can cause acute myelogenous leukemia (AML), blood clots, or liver failure.