Acquired and Inherited BMFS Flashcards
AA, PNH
Syndromes associated with AA
Schwann diamond (pancreatic insuff)
Fanconi anaemia (short, pigmentation, radial Ray)
Dyskeratosis congenita (nails, leukoplakia, skin pigmentation)
TAR
DIamond Blackfan
(RSP19 gene)
Congenital amegakaryocytic thrombocytopenia
(MPL gene mutation)
AA cytogenetic abnormality
Del 13q
Trisomy 8
Monosomy 7
The diagnosis of Aplastic Anemia usually requires the presence of pancytopenia defined as:
Neutrophil count:
Platelet count:
Hemoglobin:
Absolute Reticulocyte count:
accompanied by a hypocellular marrow without abnormal or malignant cells or fibrosis
Neutrophil count: fewer than 1.5 × 109/L
Platelet count: fewer than 50 × 109/L
Hemoglobin: less than 100 g/L
Absolute Reticulocyte count: fewer than 40 × 109/L
Degree of Severity of Acquired Aplastic Anemia
Moderately severe:
Severe:
Very severe:
Moderately severe: Hgb <100 g/L ARC <40.0 × 109/L NC <1.5 × 109/L PC <50.0 × 109/L
Severe: Hgb <90 g/L ARC <30.0 × 109/L NC <0.5 × 109/L PC <30.0 × 109/L
Very severe: Hgb <80 g/L ARC <20.0 × 109/L NC <0.2 × 109/L PC <20.0 × 109/L
Moderately severe: At the time of diagnosis at least 2 of 3 blood counts should meet these criteria
The highest frequency of aplastic anemia occurs in persons between the ages of_______years; a second peak occurs between the ages of ________years.
15 and 25 years
65 and 69 years
The male-to-female incidence ratio of aplastic anemia in most studies is approximately
One
Toxins that cause AA
- Benzene
- Chlorinated hydrocarbons
- Organophosphates
Viruses that cause AA
- Epstein-Barr virus
- Non-A, -B, -C, -D, -E, or -G hepatitis virus
- HIV
Inherited Causes of AA
- Fanconi anemia
- Dyskeratosis congenita
- Shwachman-Diamond syndrome
- Other rare syndromes
The final common pathway to the clinical disease is
A decrease in blood cell formation in the marrow
Reduced hematopoiesis in most cases of aplastic anemia results from
Cytotoxic T-cell–mediated immune suppression of very early CD34+ hematopoietic multipotential progenitor or stem cells
A relationship between acquired aplastic anemia and hereditary aplastic anemia (FA or dyskeratosis congenita) has been suggested because of the defects in _______________________
Telomerase and telomere repair
The most notorious drug documented to cause aplastic anemia
Chloramphenicol
The occurrence of aplastic anemia appears to be idiosyncratic, perhaps related to an inherited sensitivity to the nitroso-containing toxic intermediates.
Anti-malarial with evidence that it cause AA
Quinacrine (Atabrine)
The aplasia occurred during administration of the offending agent and was preceded by a characteristic rash in nearly half the cases
Causes AA because there is delayed oxidation and clearance of a related compound, acetanilide
Phenylbutazone
A histamine H2-receptor antagonist, is occasionally implicated in the onset of cytopenias and aplastic anemia, perhaps owing to a direct effect on early hematopoietic progenitor cells
Cimetidine
There is drug interactions or synergy with: carmustine and chloramphenicol
Drugs Associated with Aplastic Anemia - High Risk
Antineoplastic drugs:
Alkylating agent
Antimetabolite
Cytotoxic antibiotic
Was the first chemical linked to aplastic anemia, based on studies in factory workers before the 20th century
Benzene
An uncommon connective tissue disorder with painful swelling and induration of the skin and subcutaneous tissue, has been associated with aplastic anemia
Has been largely unresponsive to therapy
Eosinophilic fasciitis
Total-body exposure to radiation between _______Gy leads to gastrointestinal symptoms and depression of leukocyte counts, but most patients recover.
1 and 2.5 Gy
Although unusual, severe marrow aplasia can follow use of the alkylating agent,________, and may persist indefinitely.
Busulfan
Marrow aplasia may develop in patients 2–5 years after discontinuation of alkylating agent therapy.
These cases often evolve into hypoplastic myelodysplastic syndromes.
A rare exception to the negligible pathogenetic role of hematopoietic growth factors in the etiology of aplastic anemia is the homozygous or mixed heterozygous mutation of the TPO receptor gene, MPL, which can cause
Amegakaryocytic thrombocytopenia
Evolves later into aplastic anemia
Eltrombopag, a TPO receptor agonist, can stimulate mono- or, in some patients, bilineage or trilineage recovery of blood counts that may be sustained off therapy
TRUE OR FALSE
Lymphadenopathy and splenomegaly are not features of aplastic anemia; such findings suggest an alternative diagnosis such as a clonal myeloid or lymphoid disease.
TRUE
Lymphadenopathy and splenomegaly are not features of aplastic anemia; such findings suggest an alternative diagnosis such as a clonal myeloid or lymphoid disease.
TRUE OR FALSE
Significant qualitative changes of red cell, leukocyte, or platelet morphology on the blood film are features of classical acquired aplastic anemia.
FALSE
Significant qualitative changes of red cell, leukocyte, or platelet morphology on the blood film are not features of classical acquired aplastic anemia.
TRUE OR FALSE
The plasma contains high levels of hematopoietic growth factors, including EPO, TPO, and myeloid colony-stimulating factors.
TRUE
The plasma contains high levels of hematopoietic growth factors, including EPO, TPO, and myeloid colony-stimulating factors.
Other findings:
* Macrocytes may be present in the blood film and the mean cell volume increased.
* Platelets function normally.
* Occasionally only one cell line is depressed initially
TRUE OR FALSE
Plasma iron values are usually high, and Fe clearance is prolonged, with decreased incorporation into red cells.
TRUE
Plasma iron values are usually high, and Fe clearance is prolonged, with decreased incorporation into red cells.
Marrow Findings in Aplastic anemia
Numerous spicules with empty, fat-filled spaces, and relatively few hematopoietic cells
Refers to spicules that are cellular or even hypercellular
“hot spots”
These focal areas of residual hematopoiesis do not appear to be of prognostic significance.
Cytogenetic analysis in aplastic anemia is
Normal
Clonal cytogenetic abnormalities in otherwise apparent aplastic anemia is indicative of an underlying hypoplastic clonal myeloid disease.
Imaging that can be used to distinguish between marrow fat and hematopoietic cells
Magnetic resonance imaging
Magnetic resonance imaging studies of bone may be useful in differentiating severe aplastic anemia from clonal myeloid syndromes. The former gives a fatty signal and the latter a diffuse cellular pattern.
A reticulocyte percentage of less than ______% is strongly indicative of aplastic erythropoiesis and, when coupled with leukopenia and thrombocytopenia, points to aplastic anemia.
0.5%
As many as_____ of patients with otherwise typical aplastic anemia have evidence of glycosylphosphatidylinositol molecule defects and diminished phosphatidylinositol-anchored protein on leukocytes and red cells as judged by flow cytometry, analogous to that seen in PNH.
50%
As many as____% of patients with aplastic anemia have a five-year probability of myelodysplasia developing.
20%
Mutations that are increased in prevelance with patient age
ASXL1 and DNMT3A