APLASTIC ANEMIA. Aplastic Anemia. Aplastic anemia is a bone marrow failure syndrome characterized by peripheral pancytopenia and marrow hypoplasia.
- Cytotoxic drugs - Antibiotics
- Chloramphenicol - Anti-inflammatory
- Anti-convulsant - Sulphonamides
- 2-3 months usually between exposure and the development of aplastic anemia.
It is believed that genetic factors play a role.
There is a higher incidence with HLA (11) histo comp.
Antigen. Immune mechanism is involved.
The latest theory is:
1. Cytopenia - Hb <10g/dL
- ANC <1,5 G/L
- PL <100 G/L
2. Bone marrow histology and cytology
- decreased marrow cellularity (< 25%)
- increased fat cells component
- no extensive fibrosis
- no malignancy or storage disease
3. No preceding treatment with X-ray or antyproliferative drugs
4. No lymphadenopathy or hepatosplenomegaly
5. No deficiencies or metabolic diseases
6. No evidence of extramedullary hematopoiesis
1.Failure of production of blood cells
a) bone marrow infiltration
- acute leukemias
- hairy cell leukemia
- multiple myeloma
- metastatic carcinoma
b) aplastic anemia
2. Ineffective hematopoesis
- myelodysplastic syndrome
- vit.B12 and folate deficiency
3. Increased destruction of blood cells
- autoimmune disorders
- paroxysmal nocturnal hemoglobinuria
4. Myelosuppression after irradiation or antiproliferative drugs
1. Severe aplastic anemia is defined if at last two of the following criteria are present:
- ANC < 0.5 G/l
- PLT < 20 G/l
- RTC < 1% (20 G/l)
Hypoplastic bone marrow (less than 25%) on biopsy
2. Very severe aplastic anemia
- criteria as above but ANC < 0.2 G/l
3. Non-severe aplastic anemia.
- Prednisolone - Antilymphocyte glob.
- Cyclosporin - Anti T cells abs.
- correction of hematopoietic defect
- long-term survival: 80% - 90% (HLA-matched sibling donor)
- majority of the patients appear to be cured
- age below 40
- suitable donor available in less than 30% (sibling)
- 25-40% risk of GVHD
- 5-15% risk of graft failure in multitransfused patients
-high mortality after MUD-HSCT
- solid tumors (12%)
1. „Watch and wait”
2. Androgens (?)
3. Supportive care: blood and platelet transfusion, antibiotics, growth factors
4. Immunosuppressive treatment in selected patients