Myelofibrosis (idiopathic myelofibrosis; myeloid metaplasia; agnogenic myeloid metaplasia)

• What is Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• Statistics on Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• Risk Factors for Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• Progression of Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• Symptoms of Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• Clinical Examination of Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• How is Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia) Diagnosed?
• Prognosis of Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)
• How is Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia) Treated?
• Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia) References

What is Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)

Myelofibrosis is a disorder of the bone marrow in which the marrow is replaced by fibrous (scar) tissue.

Statistics on Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)

Fewer than 100 cases of pediatric MF have been reported worldwide. This is likely an under-representation because cases associated with acute megakaryoblastic leukemia (the most common association) are not generally reportable.

Of the roughly 500 new cases of pediatric acute nonlymphoid leukemia (ANLL) in the United States annually, approximately 5% are megakaryoblastic (M7 subtype, AMKL). If as few as 20% of these patients have a significant degree of MF, this would yield roughly 5 new cases per year. Other cases of MF (i.e. not associated with AMKL) likely total only a handful per year as well.

Internationally:
Cases of pediatric MF have been described in association with tuberculosis (in Pakistan) and visceral leishmaniasis (in Sudan). Thus, MF is presumably more common in areas of endemicity for these 2 diseases. Epidemiological data are not available.

Mortality/Morbidity:
MF causes, or accompanies conditions that cause, disruption of hematopoiesis. Patients may experience anaemia, neutropenia, and/or thrombocytopaenia. Patients may also experience pain secondary to hepatosplenomegaly.

 

• Neutropenia may lead to opportunistic infections, such as bacterial sepsis, oral thrush, or systemic fungal infections.
• Thrombocytopenia may lead to hemorrhage.
• The prognosis for individual patients with MF depends on the underlying disease process and its potential for treatment. Most cases of C-AMF have eventually ended in death; the course is usually fulminant.Sex:
  In published cases of pediatric MF, females outnumber males by a ratio of approximately 2:1.Age:
  Approximately half of published cases of pediatric MF occurred in children younger than 3 years. These younger patients are more likely to have Down syndrome, rickets, or a familial (possibly autosomal recessive) form of MF. Among older patients, ANLL, systemic lupus erythematosus, and tuberculosis are the most common associations.

  Risk Factors for Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)

  The disorder usually develops slowly, in people over 50 years old.

  How is Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia) Diagnosed?

  Physical examination shows an enlarged spleen. Later in the disease, it may also show an enlarged liver.

  Prognosis of Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia)

  The average survival of people with myelofibrosis is about 5 years. However, many people survive for decades. In the end stages, myelofibrosis is a wasting, debilitating illness.

  How is Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia) Treated?

  There is no specific treatment for primary myelofibrosis. Blood transfusions are given to correct anaemia. Recombinant erythropoietin or androgens may stimulate red blood cell production and may be beneficial. A splenectomy (removal of the spleen) may help if the enlarged size of the spleen causes symptoms.

  Radiation and chemotherapy may also be used. In young people, bone marrow transplants appear to improve the outlook.

  Myelofibrosis (Idiopathic myelofibrosis; Myeloid metaplasia; Agnogenic myeloid metaplasia) References

  [1] eMEDICINE
  [2] Kumar P, Clark M. CLINICAL MEDICINE. WB Saunders 2002 Pg 442
  [3] MEDLINE Plus