Myelodysplastic syndrome - a wide spectrum of pathologies that are united by a common pathogenetic mechanism of development lies in the combination of dysplastic changes in the bone marrow and cytopenia circulating blood.Each of the diseases associated with the development of myelodysplastic syndrome, creates an increased risk of developing acute myeloid leukemia.
Recently, the issue of myelodysplastic syndrome given a huge amount of scientific work, as incidence of this pathology has increased significantly, and the generally accepted effective therapy has not yet been developed.In addition, there is increase in the incidence of primary myelodysplastic syndrome, which affects young adults, due to significant environmental degradation.
risk of developing myelodysplastic syndrome comprise mainly elderly patients.
Myelodysplastic syndrome in children are the exception to the rule, as the early detection of this condition is extremely difficult.
reasons myelodysplastic syndrome
overwhelming majority of cases of myelodysplastic syndrome refers to the category of idiopathic etiopathogenetic option that can not determine the exact cause of development.Secondary myelodysplastic syndrome occurs exclusively among patients with cancer, and the debut of its development to the period after the application of chemotherapy.This category of patients characterized by extremely aggressive course of myelodysplastic syndrome, as well as resistance against medical therapy.Drugs that are used in the treatment of cancer (cyclophosphamide, topotecan) have a damaging effect on the gene that triggers the development of myelodysplastic syndrome.
There is a wide range of modifiable risk factors are eliminated, it is possible to avoid the development of myelodysplastic syndrome, which include smoking, exposure to ionizing radiation and benzene vapor.
Most oncologists is of the opinion that the main backdrop for the development of acute leukemia is a myelodysplastic syndrome.Refractory anemia is the most common form of myelodysplastic syndrome and many experts in the practice of these concepts are identified.The fundamental difference of refractory anemia from the classical variant reduction in hemoglobin concentration in the blood, is that when myelodysplastic syndrome in the bone marrow of the patient accumulates a large number of blast cells that make up 30% of the cellular composition.
myelodysplastic syndrome in the development of great importance efficiency cell production in the bone marrow.As a result of organic and morphological changes of the bone marrow in the patient develop compensatory mechanisms of extramedullary hematopoiesis accompanied by hepatosplenomegaly.Pathogenetic basis of myelodysplastic syndrome constitutes a violation of proliferation and maturation of blood cells at the level of the bone marrow, resulting in a large number of blast cells that have all the features of malignancy.
symptoms of myelodysplastic syndrome
Clinical manifestations of myelodysplastic syndrome is directly dependent on the extent of myelopoiesis, so in the early stages of the disease the patient has an asymptomatic period that can last for a long time.In a situation where a patient with myelodysplastic syndrome occurs due to the preemptive symptom of anemia, he observed increased weakness, marked pallor of visible skin, lack of appetite.
increased susceptibility to disease contagious nature suggests neutropenia.In addition, in this category of patients have an increased risk of inflammatory complications.However, the most difficult on the impact on the health of the patient is thrombocytopenic component myelodysplastic syndrome, which manifests itself in the development of hemorrhagic symptom of increased bleeding, frequent episodes of epistaxis and development of elements of petechial rash on the skin.
Qualitative diagnosis of myelodysplastic syndrome should include an assessment of the intensity of the clinical manifestations, as well as changes in cellular structure, not only the peripheral blood and bone marrow aspirate.So, when it detects signs of refractory anemia, leukopenia and thrombocytopenia, as well as a combination of these disorders in the elderly should assume the presence of myelodysplastic syndrome.
Refractory anemia is characterized by a combination with anisocytosis and macrocytosis, which manifests itself in increasing the average number of erythrocyte cell volume.Thrombocytopenia with myelodysplastic syndrome often does not reach critical values, however, accompanied by the change of size of platelet cells, as well as lower their granularity.Not necessarily with the myelodysplastic syndrome should be a decline in the white blood cells.More specific criteria is a change in leukocyte cytoplasmic granularity psevdopelgerovskih with the presence of cells.Increasing the concentration of monocyte blood cells favors the development of chronic myelomonocytic leukemia type.
high-precision methods of diagnosis, has almost 100% certainty is immunophenotyping and cytochemical analysis of the bone marrow aspirate, allowing to determine the specific enzymes is specific for the blasts.
treatment of myelodysplastic syndrome
The decision on the choice of tactics of patients with myelodysplastic syndrome depends on the severity of the laboratory manifestations.Thus, the absence of signs of hemorrhagic syndrome, severe anemia, as well as high-risk for complications of an infectious nature is the basis for the use of delaying tactics in relation to the patient.In this situation shows a dynamic monitoring of the laboratory criteria for hemodialysis and myelopoiesis.
Application of therapeutic techniques for the correction of myelodysplastic syndrome is justified only in the case of clinical manifestations, as well as increased risk of transformation to leukemia.As remedial measures with myelodysplastic syndrome apply both conservative and surgical techniques.
most widespread so-called accompanying replacement therapy, which involves the intravenous administration of blood components in the form of packed red blood cells or platelet.Note that prolonged therapy with gemokomponentov inevitably provokes iron oversaturation of the patient, which increased concentration has a toxic effect on all organs and structures, causing a violation of their functions.Given this feature transfusions should be combined with agents, iron binding and promotes its elimination from the organism (Desferal at a daily dose of 20 mg per 1 kg body weight parenterally).
Parenteral administration of erythropoietin, thrombopoietin and granulocyte colony stimulating factor is used as an additional symptomatic treatment, and in no way affects the life expectancy of the patient, which in this situation is a priority measure of the effectiveness of the treatment of myelodysplastic syndrome.Availability
patient refractory anemia as one of the components of myelodysplastic syndrome is the rationale for the use of immunosuppressive agents (Lenalipomid in a daily dose of 25 mg).
drug with proven efficacy in preventing the development of leukemia during Azacitidine is myelodysplastic syndrome, the use of which is carried out in a specific pattern.The first course of therapy lasts seven days, during which the patient intravenously Azacitidine administered in a daily dose of 75 mg / m2.During the subsequent treatment cycles daily dose for a patient is calculated in the ratio of 100 mg / m2.Multiplicity of course therapy is one week every month.Note that the effect of the azacytidine can be very intense, and therefore, each receiving the drug should be preceded by a study of the clinical analysis of blood.Evaluation hematological changes should be performed after dosing.The absolute contraindication to the use of azacitidine is the presence of the patient's severe organic disease of the liver and kidneys, as the drugs in this pharmacological group is vysokogepatotoksichnymi.Due to the fact that the metabolic products of the decay of azacytidine are eliminated via renal excretory function, the conditions for toxic damage these structures, so the use of the drug should be under the control of the dynamic performance of creatinine and urea in the blood as the main marker of kidney failure.
Despite the positive results of drug correction myelodysplastic syndrome, the only pathogenetically substantiated treatment, allowing 95% achieved complete remission is allogeneic transplantation of hematopoietic stem cell substrate, but the scope of this method of treatment is the category of patients older than 55 years,It limits its use.These restrictions are due to the fact that elderly patients are difficult to tolerate chemotherapy, which shall be required in preparation for a patient for transplantation.Furthermore, it should be borne in mind that 10% of patients may develop after the transplantation graft rejection, which is a life-threatening patient condition.Recently successfully applied stem cell transplantation is not retrieved from the bone marrow and peripheral blood from circulating.
Myelodysplastic Syndrome forecast
Mostly forecast at some form of myelodysplastic syndrome depends on the current pathogenetic variants of this disease, as well as the presence or absence of severe complications.
Recent research in hematology have been devoted to the development of criteria for evaluating the prognosis of life of patients suffering from myelodysplastic syndrome.In practice, hematology and transfusion using the international classification of IPSS, which is allocated according to the three major risk groups (low, intermediate and high).The main parameters in evaluating prognosis in myelodysplastic syndrome appears the percentage of blast cells in the bone marrow, the profile of chromosomal abnormalities, as well as the severity of cytopenia.The most favorable course observed in patients who have marked 0 points classification IPSS.Life expectancy at high risk for this classification is not more than 6 months.
Myelodysplastic syndrome - a doctor will help ?In the presence or suspected development of myelodysplastic syndrome should immediately consult a doctor such as a hematologist, Transfusion medicine, immunology and oncology.