These effects are harmful, and they can be life-threatening.

Fibrotic bone marrow no longer adequately produces blood cells.

The effects of myelofibrosis can range from mild (almost no symptoms) to severe (life-threatening).

Lab professional with microscope analyzes blood and bone marrow for signs of myelofibrosis

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How Common Is Myelofibrosis?

The worldwide incidence and distribution of the disease in most countries is not known.

The treatments for myelofibrosis can have side effects that are difficult for some people to tolerate.

The average age of diagnosis is 64, and the condition typically develops after age 50.

It can occur at any age, however.

Children can get myelofibrosis, although it is extremely rare.

When they do, its usually diagnosed before age 3.

Female children are more likely to develop myelofibrosis during childhood than male children.

Causes of Myelofibrosis and Risk Factors

Myelofibrosis is characterized as either primary or secondary.

Secondary myelofibrosis develops due to another disease.

Primary myelofibrosis is considered idiopathicwithout a known predisposing cause.

The mutation usually occurs without being inherited.

It develops when the bone marrow is damaged, which can cause fibrosis.

Conditions that can lead to secondary myelofibrosis include:

What Are the Mortality Rates for Myelofibrosis?

Progression to cancer can also increase the risk of death.

Various systems are used in prognosis, which is predicting an individual’s estimated survival with myelofibrosis.

Summary

Myelofibrosis is a rare bone marrow disease.

The condition causes changes in blood cell production, and this leads to many medical complications.

Myelofibrosis can be associated with previous bone marrow cancer, and it can also lead to bone marrow cancer.

Primary myelofibrosis occurs due to changes in genes that are usually not inherited.

Survival is improving with new therapies, including JAK inhibitors and bone marrow transplant.