2. Definition
• Aplastic anemia refers to a syndrome of
chronic primary hematopoietic failure and
attendant pancytopenia
– Anemia
– Neutropenia, and
– Thrombocytopenia
5. Aplastic Anemias
Fanconi anemia
• AR disorder
• Defect in DNA repair
• Marrow hypoplasia
• Hypoplasia of kidney, spleen
• Hypoplastic anomalies of bone – Thumb, Radius
7. Aplastic Anemias - Pathogenesis
Environmental factors trigger the production of
genetically altered stem cells
1. Immunologically mediated suppression of
stem cells
By cytokines released by T cells
2. Intrinsic abnormality of stem cells
↓ proliferation & differentiating capacity
13. Clinical Features
• Can occur at any age
• Onset is usually insidious
• Initial manifestations vary depending on the
affected cell line
• Splenomegaly is absent
• Reticulocytopenia is the rule
If it is present, the diagnosis of
aplastic anemia should be
seriously questioned
14. Aplastic Anemia
• DD
– MDS
– Aleukemic leukemia
Treatment
• Allogenic BMT
• Antithymocyte globulin along with
cyclosporine
17. • It’s a primary marrow disorder in which only
erythroid progenitors are suppressed
• Causes:
– Thymoma
– Large granular lymphocytic leukemia
– Drug exposures
– Autoimmune disorders
– Parvovirus infection B19
21. Polycythemia
• Myeloproliferative disorder
– Unregulated proliferation of erythroid elements in
BM
– ↑ Erythrocyte concentration in peripheral blood
• Also ↑ other blood cells
• Synonyms: Polycythemia rubra vera, primary
polycythemia, erythemia
22. Polycythemia
• Polycythemia Vera – primary
• Secondary Polycythemia
– Appropriate to erythropoietin production
• High altitude
• COPD
• Obesity
– Inappropriate to erythropoietin production
• Tumors – RCC, HCC, uterine leiomyoma
• Renal ischemia
– Familial Polycythemia
• Relative Polycythemia
– Gaisbock’s syndrome
– Dehydration
23. Polycythemia Vera
• Unknown cause
• Possible mechanisms
– Erythropoietin independent proliferation of
neoplastic stem cells
– Hypersensitivity of erythroid stem cells to
erythropoietin
– Hypersensitivity of erythroid stem cells to insulin
growth factors
– Abnormal GF that act on normal stem cells