Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome

Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome

Myelodysplastic syndrome refers to a blood disorder in which one or more cellular components (erythrocytes, leukocytes (other than lymphocytes) and platelets (or their precursor cells, megakaryocytes) cause abnormalities in blood. Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome

Myelodysplastic syndromes include:

  • Refractory anemia
  • Refractory anemia with annular sideroblasts (RARS)
  • Refractory anemia with excessive burst (RAEB)
  • Chronic myelogenous leukemia - not to be confused with CML.
  • Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome

    Exceptions include:

  • Neutropenia, anemia and thrombocytopenia (low cell count)
  • Abnormal cell granules, abnormal shape and size of nuclei
  • Chromosomal abnormalities, including chromosomal translocations.
  • Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome
epidemiology

    An estimated 7,000 to 12,000 new cases of MDS are diagnosed each year, and these are diseases of elderly. However, those who received chemotherapy for other tumors were at increased risk.

    Signs and symptoms
  • Anemia is chronic fatigue (in this case, blood transfusion is only effective treatment and can last for years)
  • Neutropenia (low white blood cell count) - increased susceptibility to infection.
  • Thrombocytopenia (low platelet count) - an increased tendency to bleed.
  • Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome

    The effects of a low cell count may be greater due to impaired cellular function than other conditions with a similar cell count and less disruption of normal function.

    All of these conditions increase risk of acute leukemia, which is notoriously untreatable ("secondary leukemia"). In RA and RARS, risk is relatively low and condition may persist for many years (eg, 10 years). In Raeb and CMML, passage of time is usually faster.

    Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome
clinical suspicion

    Normocytic anemia and reticulocytopenia, not usually diagnosed as requiring bone marrow aspiration followed by bone marrow biopsy or macrocytic anemia, but not associated with folic acid or B12 deficiency. More advanced cases may show signs of myelodysplasia.

    Diagnostics

    Required investigations include:

  • Complete blood count and blood smear
  • Bone marrow aspiration
  • In some cases: examination of chromosomes.
  • Refractory anemia (RA)

    OAK: macrocytic anemia with reticulocytopenia.

    Bone marrow: Myeloid and megakaryocytic rows in bone marrow were normal, but macrophage-like erythrocytosis was observed. Dysplasia is usually minimal.

    Refractory anemia with siderogenic cells (RAS)

    The blood and bone marrow are identical to those of RA patients, except that >15% of bone marrow progenitors are sideroblasts.

    Popular Science Health Knowledge: Clinical and Treatment of Myelodysplastic Syndrome
Refractory anemia with excess foaming agent (RAEB)

    Clinical suspicion: In addition to abnormal erythropoiesis, there are signs of significant bone marrow hematopoiesis and megakaryopoiesis.

    Diagnosis. Bone marrow contains 5% to 20% myeloid cells, 1% to 5% of which circulate in blood.

    Refractory anemia with excessive cellular transformation (RAEB-T)

    Clinical suspicion: this is a panmyeloid disease.

    Diagnosis: 20%~30% of bone marrow cells are cells, >5% of cells can be seen in blood. Orr rods are visible.

    Chronic myelogenous leukemia (CMML)

    Clinical suspicion: Hepatosplenomegaly may be present.

    Mild thrombocytopenia and mild anemia are associated with morphologically normal megakaryocytes and erythroid precursors in bone marrow.

    Diagnosis: Bone marrow contains 5-20% cells, and number of circulating monocytes > 1000/mm3.

    treatment
  • No cure (watch and wait)
  • Conservative (e.g. regular blood transfusions)
  • Chemotherapy (although patients usually do not tolerate chemotherapy well).