Aplastic anemia
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- Aplastic Anemia
- syndrome of chronic primary hematopoietic failure and attendant pancytopenia (anemia, neutropenia, and thrombocytopenia).
- Persistent marrow aplasia occur most commonly viral hepatitis of the non-A, non-B, non-C, non-G type (MCQ)
- Fanconi anemia
- autosomal recessive disorder (MCQ)
- Aplastic Anemia
- caused by defects in a multiprotein complex that is required for DNA repair (MCQ)
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- Marrow hypofunction
- accompanied by multiple congenital anomalies
- hypoplasia of the kidney and spleen
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- Bone anomalies, which most commonly involve the thumbs or radii. (MCQ)
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- Inherited defects in telomerase are found in 5% to 10% of adult-onset aplastic anemia (MCQ)
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- about 65% of cases fall into this idiopathic category. (MCQ)
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- Antithymocyte globulin and cyclosporine are used in treatment
- they suppress or kill autoreactive T-cell clones. (MCQ)
- Morphology
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- markedly hypocellular bone marrow is largely devoid of hematopoietic cells;
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- often only fat cells, fibrous stroma, and scattered lymphocytes and plasma cells remain. (MCQ)
- Marrow aspirates often yield little material (a “dry tap”);
- aplasia is best appreciated in marrow biopsies
- If the anemia necessitates multiple transfusions, systemic hemosiderosis can appear.
- Splenomegaly is characteristically absent (MCQ)
- if splenomegaly is present, the diagnosis of aplastic anemia should be seriously questioned.
- The red cells are usually slightly macrocytic and normochromic.
- Reticulocytopenia is the rule. (MCQ)
- The diagnosis rests on examination of a bone marrow biopsy.
- other causes of pancytopenia (MCQ)
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- “aleukemic” leukemia
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- myelodysplastic syndromes
- In aplastic anemia, the marrow is hypocellular (and usually markedly so), myeloid neoplasms are associated with hypercellular marrows filled with neoplastic progenitors. (MCQ)
- Bone marrow transplantation is treatment of choice in those with a suitable
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- Pure Red Cell Aplasia
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- a primary marrow disorder
- only erythroid progenitors are suppressed
- may occur in association with
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- thymoma (MCQ)
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- large granular lymphocytic leukemia
- drug exposures
- autoimmune disorders,
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- parvovirus infection (MCQ)
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- Myelophthisic anemia
- a form of marrow failure
- caused by space-occupying lesions replace normal marrow elements
- Causes
- commonest cause is metastatic cancer (MCQ)
- most often carcinomas arising in the breast, lung, and prostate. (MCQ)
- any infiltrative process (e.g., granulomatous disease) involving the marrow can produce identical findings.
- commonest cause is metastatic cancer (MCQ)
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- Leukoerythroblastosis is seen (MCQ)
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- abnormal release of nucleated erythroid precursors and immature granulocytic forms (leukoerythroblastosis) into peripheral smears
- teardrop-shaped red cells is seen (MCQ)
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- which are believed to be deformed during their tortuous escape from the fibrotic marrow.
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- Major Causes of Aplastic Anemia
- ACQUIRED
- Idiopathic
- Acquired stem cell defects
- Immune mediated
- Chemical Agents
- Dose related
- Alkylating agents (MCQ)
- Antimetabolites
- Benzene
- Chloramphenicol (MCQ)
- Inorganic arsenicals
- Idiosyncratic
- Chloramphenicol (MCQ)
- Phenylbutazone
- Organic arsenicals
- Methylphenylethylhydantoin
- Carbamazapine (MCQ)
- Penicillamine
- Gold salts
- Dose related
- Physical Agents
- Whole-body irradiation
- Viral Infections
- Hepatitis (unknown virus)
- Cytomegalovirus infections
- Epstein-Barr virus infections
- Herpes zoster (Varicella zoster)
- Idiopathic
- INHERITED
- Fanconi anemia (MCQ)
- Telomerase defects
- ACQUIRED
- Major Causes of Aplastic Anemia