The Myeloproliferative syndromes Are a group of chronic diseases that have serious consequences on the health and life in general of the people who suffer it.
The life expectancy of people with this type of syndromes is quite long, so I think it is necessary to know the disease better to understand and improve the living conditions of these people.
Characteristics of myeloproliferative syndromes
Myeloproliferative syndromes, now called myeloproliferative neoplasms, include all conditions in which at least one type of blood cell, produced in the bone marrow, develops and proliferates in an uncontrolled way.
The main difference between these syndromes and myelodysplastic syndromes is that, in myeloproliferative syndromes, bone marrow Makes cells uncontrolled, while in myelodysplastics there is a deficit in the manufacture of cells.
To understand the topic well, it is necessary to know how blood cells develop from stem cells of the bone marrow, explained in the article Myelodysplastic syndromes .
Types of Myeloproliferative Syndromes
The current classification of myeloproliferative syndromes includes:
Polycythemia vera
This syndrome is characterized by the bone marrow producing too many blood cells, especially red blood cells, which thicken the blood. It is related to the JAK2 gene, which appears mutated in 95% of cases (Ehrlich, 2016).
Essential thrombocythemia
This condition occurs when the bone marrow produces too many platelets, causing the blood to clot and form thrombi that obstruct the blood vessels, which can lead to both cerebral and myocardial infarctions.
Primary myelofibrosis
This disease, also called myeloesclerosis, occurs when the bone marrow produces too much Collagen And fibrous tissue, which lowers their ability to create blood cells.
Chronic myeloid leukemia
This syndrome, also called marrow cancer, is characterized by the uncontrolled production of Granulocytes , A type of white blood cells, which end up invading the bone marrow and other organs preventing its proper functioning.
symptom
In most cases, the symptoms are not noticeable at the onset of the disease, so people often realize that they have the syndrome in routine analytics. Except in the case of primary myelofibrosis, in which the spleen normally widens, which causes abdominal pain.
Each syndrome has a different clinical picture with characteristic symptoms, although some symptoms are present in several affections.
Polycythemia vera
The clinical manifestation includes the following symptoms:
- Non-specific symptoms (Occur in 50% of cases).
- Asthenia (Physical weakness or fatigue).
- Night sweats.
- Weightloss.
- Gout crisis.
- Epigastric discomfort.
- Generalized pruritus (itching).
- Difficulty breathing.
- Thrombotic phenomena (Occur in 50% of cases).
- Stroke.
- Angina chest.
- Infarctions.
- Intermittent claudication (muscle pain) of the lower limbs.
- Thrombosis in abdominal veins.
- Peripheral vascular insufficiency (with redness and pain in the fingers and toes that worsen with exposure to heat).
- Bleeding (Occurring in between 15 and 30% of cases).
- Epistaxis (haemorrhage of the nostrils).
- Gingivorrhages (bleeding gums).
- Digestive bleeding.
- Neurological manifestations (Occurring in 60% of cases).
- Headache .
- Tingling in hands and feet.
- Feeling of vertigo .
- Visual disturbances.
Essential thrombocythemia
The clinical manifestation includes the following symptoms:
- Disorders in the microcirculation (Occurring in 40% of cases).
- Redness and pain in the fingers and toes.
- Distal gangrene.
- Transient cerebral vascular accidents.
- Ischaemias.
- Syncopes .
- Instability
- Visual disturbances.
- Thrombosis (Occurring in 25% of cases).
- Bleeding (Occur in 5% of cases).
Primary myelofibrosis
The clinical manifestation includes the following symptoms:
- Constitutional (Occurring in 30% of cases).
- Lack of appetite.
- Weightloss.
- Night sweats.
- Fever.
- Derivatives of anemia (Occurring in 25% of cases).
- Asthenia (Physical weakness or fatigue).
- Dyspnea with exertion (feeling of shortness of breath).
- Lower extremity edema (swelling caused by fluid retention).
- Splenomegaly (Occur in 20% of cases). Swelling of the spleen with abdominal pain.
- Other causes Less frequent (occur in 7% of cases)
- Arterial and venous thrombosis.
- Hyperuricemia (increased uric acid in the blood), which can trigger in gout.
- Generalized pruritus (itching).
Chronic myeloid leukemia
Most of the symptoms are constitutional:
- Asthenia (physical weakness or fatigue).
- Loss of appetite and weight.
- Fever and night sweats.
- Trouble breathing.
Although patients may also have other symptoms such as infections, weakness and bone breakage, heart attacks, gastrointestinal bleeding, and enlarged spleen (splenomegaly).
Causes
Myeloproliferative syndromes occur because the bone marrow creates cells in an uncontrolled way, but why this happens is not at all clear. As in most syndromes, there are two types of factors that appear to be related to the onset of the syndrome:
Genetic factors
In some patients it has been found that a chromosome, called the Philadelphia chromosome , Is shorter than normal. So it seems that there is a genetic component that increases the predisposition to suffer this disease.
Environmental factors
Genetic factors alone are not explanatory of these syndromes since there are people who have not found the shortening of the Philadelphia chromosome and yet present one of the syndromes.
Some studies suggest that environmental factors such as continued exposure to radiation, chemicals or heavy metals increase the likelihood of this type of disease (as in other cancers).
Risk factor's
Other factors, such as the age or sex of the patient, may increase the risk of developing a myeloproliferative syndrome. These risk factors are described in the following table:
Treatment
There are currently no treatments available that can cure myeloproliferative syndromes, but there are treatments to alleviate the symptoms and prevent future complications that may be suffered by the patient.
The treatment used depends on the type of proliferative syndrome, although there are some indications (such as nutritional changes) that are generic for all myeloproliferative syndromes.
Polycythemia vera
The treatments used to relieve the symptoms of Polycythemia vera Are designed to reduce the number of red blood cells, using drugs and other therapies, such as phlebotomy.
Phlebotomy is performed to evacuate a certain amount of blood, through a small incision, to lower red blood cell levels and to decrease the likelihood of patients suffering from a heart attack or other cardiovascular disease.
This is a first-line treatment, that is, the first treatment that the patient receives once he has been diagnosed. This is because it has proven to be the only treatment that increases the life expectancy of people suffering from polycythemia vera.
Treatment with medication includes:
- Myelosuppressive therapy with hydroxyurea (trade names: Droxia or Hydrea) or anagrelide (trade name: Agrylin). These medicines reduce the number of red blood cells.
- Low doses of aspirin, to reduce fever and redness and burning of the skin.
- Antihistamines, to reduce itching.
- Allopurinol, to reduce the symptoms of gout.
In some cases it is also necessary to apply other therapies, such as blood transfusions if the patient has anemia or surgery to remove the spleen if it has increased in size.
Essential thrombocythemia
The Thrombocythemia Essential is basically mediation, which includes:
- Myelosuppressive therapy with hydroxyurea (trade names: Droxia or Hydrea) or anagrelide (trade name: Agrylin), to reduce red blood cell levels.
- Low doses of aspirin, to reduce headaches and redness and burning of the skin.
- Aminocaproic acid, to reduce bleeding (usually used before surgery, to prevent bleeding).
Primary myelofibrosis
The Myelofibrosis Primary treatment is basically medication, although in other severe cases other treatments such as surgeries, transplants and blood transfusions may be necessary.
Treatment with medication includes:
- Myelosuppressive therapy with hydroxyurea (trade names: Droxia or Hydrea), to reduce the number of white blood cells and platelets, improve the symptoms of anemia and prevent some complications such as enlargement of the spleen.
- Thalidomide and lenalidomide, to treat anemia.
In some cases the spleen significantly increases its size and surgery is necessary to remove it.
If the person has severe anemia it will be necessary to have blood transfusions, in addition to continuing with the medication.
In the most severe cases it is necessary to perform a bone marrow transplant , To replace damaged or destroyed cells with healthy cells.
Chronic myeloid leukemia
The number of treatments available for the Myeloid leukemia Chronic disease has increased markedly and mainly include drug therapies and transplants.
Treatment with medication includes:
- Targeted therapy for cancer, with medications such as dasatinib (trade name: Sprycel), imatinib (trade name: Gleevec) and nilotinib (trade name: Tasigna). These drugs affect certain proteins in cancer cells that keep them from multiplying in an uncontrolled way.
- Interferon, to help the patient's immune system fight against cancer cells. This treatment is only used if a bone marrow transplant can not be performed.
- Chemotherapy , Drugs such as cyclophosphamide and cytarabine are given to kill cancer cells. It is usually done just before the patient receives a bone marrow transplant.
In addition to medical therapy, there are other treatments that can significantly improve patients' conditions and life expectancy, such as bone marrow transplantation or Lymphocytes .
References
- Ehrlich, S.D. (February 2, 2016). Myeloproliferative disorders . Obtained from University of Maryland Medical Center:
- Josep Carreras Foundation. (S.f.). Chronic myeloproliferative syndromes . Retrieved on June 17, 2016, from the Josep Carreras Foundation
- Gerds, Aaron T. (April 2016). Myeloproliferative Neoplasms . Obtained from Cleveland Clinic