Myelofibrosis (MF) is a disease that usually develops slowly over a long period of time. Not everyone experiences symptoms, and the most common symptoms are often related to other, more common diseases.

Still, knowing the symptoms of MF can help you be more prepared and start on a treatment plan as early as possible.

In the early stages of MF, many people do not experience symptoms. However, as the disease progresses and normal blood cell production in the body becomes more disrupted, you may begin to experience symptoms. These can include:

  • pale skin
  • easy bruising or bleeding
  • excessive sweating while sleeping
  • fever
  • frequent infections
  • fatigue, feeling weak, or feeling short of breath (usually
    caused by anemia)
  • bone pain
  • pain or a feeling of fullness below your ribs, usually on
    the left side (caused by an enlarged spleen)

If you’re experiencing any of these symptoms for an extended period of time, contact your doctor. They will perform a physical exam and possibly other tests, as well as discuss the symptoms you’ve been having. These other tests may include blood tests, imaging tests, and a bone marrow exam.

If your primary doctor thinks you may have MF, they will most likely refer you to a hematologist, or doctor who specializes in blood and bone marrow disorders.

As MF progresses, you may have more severe symptoms. As bone marrow continues to turn to scar tissue and blood cell production becomes more abnormal, you also may begin to experience more serious side effects or complications, such as:


An enlarged spleen can cause abdominal and back pain. This can be a symptom of MF. Joint pain can also be present in MF as bone marrow hardens and connective tissue around the joints becomes inflamed.


MF causes the body to produce more uric acid than normal. The increased uric acid can crystallize and settle around joints, causing pain and swelling.

Increased pressure on blood flowing into your liver

Blood flows from the spleen into the liver to be processed. An enlarged spleen will cause the amount of blood flowing into the liver, and also the blood pressure, to increase. This is called portal hypertension. The increased blood pressure can force extra blood into smaller veins in the digestive system, such as the esophagus or stomach. This could cause these smaller veins to rupture and bleed.


As MF progresses, your platelet count could drop below normal. A low number of platelets (thrombocytopenia) can lead to easy bleeding. If you’re considering a surgical procedure, this is an important complication for you and your doctor to consider.

Formation of blood cells outside the bone marrow

This can lead to clumps or tumors of blood cells in other parts of the body, causing complications such as bleeding, nerve damage, or seizures.

Acute leukemia

About 12 percent of people with MF will develop acute myelogenous leukemia (AML). AML is a quickly progressing cancer of the blood and bone marrow.

While the symptoms of MF can be mistaken for other conditions, talk to your doctor if you experience any of them. Being proactive can help you avoid any future complications.