Myelofibrosis (NORD)
12,505views
00:00 / 00:00
Videos
Notes
Myelofibrosis (NORD)
Information for patients and families
Osmosis
Using an inhaler: Information for patients and families
Managing diabetes during the holidays: Information for patients and families
The flu vaccine: Information for patients and families
Bike helmet safety: Information for patients and families
The Primary School
Toxic stress: Information for patients and families (The Primary School)
ADHD: Information for patients and families (The Primary School)
Asthma: Information for patients and families (The Primary School)
Childhood nutrition and obesity: Information for patients and families (The Primary School)
Childhood oral health: Information for patients and families (The Primary School)
Food allergies and EpiPens: Information for patients and families (The Primary School)
Glut1 Deficiency Foundation
Glut1 deficiency syndrome (Glut1 Deficiency Foundation)
The National Organization for Rare Disorders (NORD)
Narcolepsy (NORD)
Adrenoleukodystrophy (NORD)
Zellweger spectrum disorders (NORD)
Glycogen storage disease type II (NORD)
Metachromatic leukodystrophy (NORD)
Gaucher disease (NORD)
Niemann-Pick disease types A and B (NORD)
Fabry disease (NORD)
Tay-Sachs disease (NORD)
Mucopolysaccharide storage disease type 1 (Hurler syndrome) (NORD)
Mucopolysaccharide storage disease type 2 (Hunter syndrome) (NORD)
Phenylketonuria (NORD)
Cystinuria (NORD)
Aromatic L-amino acid decarboxylase deficiency (NORD)
Cerebrotendinous xanthomatosis (NORD)
Classical homocystinuria (NORD)
Autoimmune polyglandular syndrome type 1 (NORD)
Thyroid eye disease (NORD)
Opsoclonus myoclonus syndrome (NORD)
Thyroid eye disease (NORD)
Short bowel syndrome (NORD)
Bile synthesis disorders (NORD)
Eosinophilic esophagitis (NORD)
Cyclic vomiting syndrome (NORD)
Polycythemia vera (NORD)
Essential thrombocythemia (NORD)
Myelofibrosis (NORD)
Warm autoimmune hemolytic anemia and cold agglutinin (NORD)
Sickle cell disease (NORD)
Waldenstrom macroglobulinemia (NORD)
Post-transplant lymphoproliferative disorders (NORD)
Cytomegalovirus infection after transplant (NORD)
Mycobacterium avium complex (NORD)
Congenital cytomegalovirus (NORD)
Opsoclonus myoclonus syndrome (NORD)
Spinocerebellar ataxia (NORD)
Early infantile epileptic encephalopathy (NORD)
IgA nephropathy (NORD)
Focal segmental glomerulosclerosis (NORD)
Alagille syndrome (NORD)
NGLY1 deficiency (NORD)
Recurrent pericarditis (NORD)
Assessments
Myelofibrosis (NORD)
Flashcards
0 / 7 complete
USMLE® Step 1 questions
0 / 2 complete
High Yield Notes
10 pages
Flashcards
Myelofibrosis (NORD)
of complete
Questions
USMLE® Step 1 style questions USMLE
of complete
| Laboratory value | Result |
| Hemoglobin | 9.5 g/dL |
| Hematocrit | 28.5% |
| Leukocytes | 2,700/mm3 |
| Platelets | 100,000/mm3 |
Biopsy of the bone marrow biopsy shows increased fibrosis and reduced cell count. Polymerase chain reaction testing reveals a mutation in a gene encoding for a non-receptor tyrosine kinase. Which of the following diseases is also caused by an identical mutation?
Memory Anchors and Partner Content
External References
First Aid
2022
2021
2020
2019
2018
2017
2016
Myelofibrosis p. 441
dacrocytes in p. 422
Splenomegaly
myelofibrosis p. 441
External Links
Transcript
Content Reviewers
Rishi Desai, MD, MPHContributors
Stefan Stoisavljevic, MD
Evan Debevec-McKenney
Myelofibrosis is a disease in which the bone marrow within a bone gets replaced by connective tissue in a process called fibrosis.
Since the bone marrow’s main role is to produce erythrocytes or red blood cells, leukocytes or white blood cells, and thrombocytes or platelets, the process of fibrosis interferes with production of these cell types.
Now, normally, the vast majority of bone marrow is made of hematopoietic cells which are the early progenitor cells that can differentiate into other cell types.
In addition to these cells there are fibroblasts, which are connective tissue cells.
Now, myelofibrosis can be primary or secondary.
Primary myelofibrosis is caused by a gene mutation within hematopoietic cells, which activates a set of enzymes that together are called the JAK-STAT pathway.
The mutation specifically causes the enzymes in the JAK-STAT pathway to go into overdrive so that the cells begin to mature and divide rapidly, quickly filling up the bone marrow.
A large majority of these cells turn into megakaryocytes which go on to make platelets.
These megakaryocytes release cytokines, which are molecules that create inflammation.
And one of these cytokines is fibroblast growth factor which activates fibroblasts.
The activated fibroblasts engage in the process of fibrosis - they make lots of connective tissue that ultimately begins to fill up and scar the bone marrow and replaces hematopoietic cells.
In response, the hematopoietic cells migrate to liver, spleen, and lungs - a process called extramedullary hematopoiesis.
These tissues enlarge and sometimes become dysfunctional.
The extramedullary hematopoiesis is often not able to fully compensate for the loss of bone marrow hematopoiesis, and it can lead to a shortage of all blood cell lines - called pancytopenia.
Summary
Myelofibrosis is a type of bone marrow disorder that affects the production of blood cells. In Myelofibrosis, the bone marrow tissue is replaced with fibrotic tissue, which interferes with blood cell production. Symptoms include anemia, fatigue, bone pain, itching, fever, and weight loss. Treatment options may include medications like ruxolitinib, bone marrow transplants, and blood transfusion.
Copyright © 2023 Elsevier, except certain content provided by third parties
Cookies are used by this site.
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.
