Myelodysplastic syndrome

The myelodysplastic syndromes are a collection of haematological conditions including:

• Refractory anaemia (RA)
• Refractory anaemia with ring sideroblasts (RARS)
• Refractory anaemia with excess of blasts (RAEB)
• Chronic myelomonocytic leukaemia (CMML) - not to be confused with CML

All the conditions show abnormalities in the production of one or more of the cellular components of blood (red cellss, white cellss (other than lymphocytes) and platelets (or their progenitor cells, megakaryocytes).

Table of contents

1 Signs and symptoms 2 Diagnosis 3 Epidemiology 4 Therapy

Signs and symptoms

These abnormalities include:

• neutropenia, anaemia and thrombocytopenia (low cell counts of each)
• abnormal granules in cells, abnormal nuclear shape and size
• chromosomal abnormalities, including chromosomal translocations.

Symptoms of myelodysplastic conditions:

• Anaemia - chronic tiredness (in this condition blood transfusion is the only effective treatment, which can carry on for years)
• Neutropenia (low white cell count) - increased susceptibility to infection
• Thrombocytopenia (low platelet count) - increased susceptibility to bleeding

Because the cellular function is impaired the effects of low cell counts may be greater than in other conditions with a similar cell count be less impairment of normal function.

All these conditions have an increased risk of developing acute leukaemia, which is notoriously resistant to treatment ("secondary leukaemia"). In RA and RARS the risk is relatively low and the condtion may persist for many years (eg 10). In RAEB and CMML the time course is typically quicker.

Diagnosis

Investigation:

• Full blood count and examination of blood film
• Bone marrow aspirate
• In some cases: chromosome studies.

Epidemiology

These are mostly conditions of the elderly. However, there is an increased risk in those people who have had chemotherapy for other tumours.

Therapy

Treatment:

1. No treatment (watch and wait)
2. Conservative (eg periodic blood transfusion)
3. Chemotherapy (although often patients do not tolerate chemotherapy well).

Health science - Medicine - Hematology

Hematological malignancy and White blood cells

Lymphoma (Hodgkin's disease;, NHL) - Leukemia (ALL, AML, CLL, CML) - Multiple myeloma; - MDS - Myelofibrosis - Myeloproliferative disease; (Thrombocytosis, Polycythemia) - Neutropenia

Red blood cells

Anemia - Hemochromatosis - Sickle-cell anemia; - Thalassemia - other hemoglobinopathies

Coagulation and Platelets

Thrombosis - Deep venous thrombosis; - Pulmonary embolism; - Hemophilia - ITP - TTP