Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Hematology 2 > Lecture 11 Myelodysplastic Syndromes Chapter 33 > Flashcards

Lecture 11 Myelodysplastic Syndromes Chapter 33 Flashcards

1
Q

What may be some causes of DMD (Myelodysplastic) Syndrome?

A

Causes unknown.
Some cases linked to X ray therapy, chemotherapy, work or hobby exposure to chemicals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What age ranges does myelodysplastic syndromes occur more frequently in?

A

Elderly 70-90 years.

(Versus other leukemias which often occurred more in the 50-60 year range).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the mechanism by which myelodysplastic syndromes occur?

A

Pathophysiology poorly understood.
Two theories:
1. Suppression of pluripotent stem cell causes marrow hypoplasia and pancytopenia.
2. Suppression of committed stem cell lines causes selective marrow hypoplasia with singular cytopenias.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Do Dysmyelopoietic Syndrome (DMPS) stem cell lines have the ability to mature to end stage? What about appearance and function?

A

DMPS stem cell line has the ability to mature to end stage but are abnormal in appearance and function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does Dyserthropoiesis mean?

A

Abnormal maturation of erythrocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the overall effect of Dyserthropoiesis with ineffective erythropoiesis?

A

Dyserthropoiesis with ineffective erythropoiesis explains anemia with mature but oval macrocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the state of neutrophils in myelodysplastic conditions?

A

Neutropenia with morphologically and functionally abnormal mature forms such as pseudo pelger-huet and hypogranular neutrophils (associated with MDS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the result of the neutropenia and functionally abnormal mature neutrophil forms?

A

Infection and fever.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the state of the platelet counts and morphology in myelodysplastic conditions?

A

Decreased platelet counts with abnormal morphology and qualitative defect (abnormal function) may be present.

Suppression and dysplasia of megakaryocytes accounts for thrombocytopenia, abnormal appearing platelets with bleeding problems.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the clinical presentation of myelodysplastic conditions?

A
  1. Fatigue, fever and bleeding (similar ot other leukemias)
  2. Early stage of DMPS, asymptomatic but later:
    - Pallor due to anemia
    - Fever due to infection
    - petechiae or echymoses due to thrombycytopenia
  3. Spleen may be slightly enlarged especially in CMML (due to high WBC count) but usually no lympadenopathy.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In myelodysplastic conditions what causes the fatigue, fever and bleeding systems (different from other leukemias)?

A

Unlike Acute leukemias, this is not due to crowding out in the bone marrow but rather to decreased production (quantitative) and abnormal function (qualitative) defects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

*What morphologies may be present in the blood in myelodysplastic conditions (Peripheral Blood - Erythropoiesis)?

A

Poikilocytosis
- Ovalocytes
- Oval Marcocytes
- Tear drop
- NRBC’s
- Basophilic stippling
- Howell-Jolly bodies
- Pappenheimer Bodies
Microcytic / hypochromic or dimorphic picture (due to impaired hemoglobinization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the 5 different diseases in the classification of Dysmyelopoietic Syndromes?

A

Types 1, 2, 3, 4, and 5 are:
1. Refractory Anemia (RA)
2. Refractory Anemia with Ringed Siderblasts
3. Refractory Anemia with Excess Blasts (RAEB)
4. Chronic Myelomonocytic Leukemia (CMML)
5. Refractory Anemia with Excess Blasts in Transformation (RAEBIT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What characteristics abnormal erythropoiesis morphologies can be seen in the bone marrow in Dysmyelopoietic Syndromes?

A
  1. Quantitative abnormalities range from red cell aplasia (severe decrease) to erythroid hyperplasia.
  2. Megaloblastoid forms (abnormal maturation) which shows more open chromatin pattern). Nucleus less mature than cytoplasm.
    3.RBC precursor nucleus may have irregular shapes - simple indentation to complex irregular forms (multinuclearity, clover leafs & giant forms).
  3. Ringed sideroblasts (iron filled mitochrondria)
  4. Shift in RBC maturation (increase in erythoblasts).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are ringed sideroblasts?

A

NRBC’s with five or more iron granules occupying at least 1/3 of the circumference of the nucleus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of granulopoiesis abnormal morphology can exist in Myelodysplastic Syndromes?

A
  1. Variety of changes - from decreased granulopoiesis to marked hyperplasia.
  2. Left shift with increase in myeloblasts (depends on type of DMPS). Blasts may have auer rods.
  3. Pseuo Pelger-Huet (pelgeroid), hypersegmentation of the nucleus in neutrophils may also be present.
  4. Hypogranulation with occ’l case demonstrating coarse abnormal granules.
  5. Eosinophils, basophils rarely are also hypogranular.
  6. Neutrophils with monocytoid features especially in CMML. Cells having cytochemical properties of both neutrophils and monocytes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What type of megakaryopoiesis abnormal morphology can exist in Myelodysplastic Syndromes?

A
  1. Maturation arrest, showing small to medium size cells with single or bilobed nuclei (Normally is large cell w/ 4-8 lobes).
  2. Micro or dwarf megakaryocytes may be found in bone marrow and peripheral blood.
  3. Platelet morphology is usually abnormal with large, hypogranular forms present.
  4. Megakaryoblasts in peripheral blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What type of quantitive megakaryopoiesis abnormalities can exist in Myelodysplastic Syndromes?

A
  1. Absence of megakaryocytes to hyperplasia (bone marrow).
  2. Peripheral blood platelet count may be normal, usually decreased and rarely increased.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why is Refractory Anemia called a low grade DMPS?

A

Because it is the most difficult to recognize due to limited number of features available for differentiation. Morphology is similar to Megaloblastic Anemias.

Least severe of the Myelodysplastic Syndromes (DMPS).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

*What are the main features of Refractory Anemia (RA)?

A

Main features are anemia (persistent mild to severe), megaloblastoid features in the marrow and oval macrocytes in the peripheral blood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the MCV and RDW values like in Refractory Anemia?

A

MCV and RDW usually elevated with occ’l dimorphism.

22
Q

What may be seen in the peripheral blood in Refractory Anemia?

A
  1. Dysplastic NRBC, pappenheimer bodies (RBC’s with iron inclusions) and polychromasia may be found in peripheral blood.
  2. Decreased reticulocyte count.
  3. Dysgranulopoiesis and dysmegakaryopoiesis may or may not be present.
  4. WBC and Platelet count: Normal or Low
  5. Blasts <1% in Peripheral Blood;
  6. 1/3 or patients are bicytopenic and 20% are pancytopenic.
23
Q

What may be seen in the bone marrow in Refractory Anemia?

A
  1. Cellularity most often normal or increased with hypocellullarity in rare cases.
  2. Erythroid hyperplasia with megaloblastoid features with common finding.
  3. Ringed sideroblasts (<15%) may be seen.
  4. Bone Marrow iron normal or increased.
  5. Increased numbers and abnormal megakaryocytes may be present.
  6. <5% blasts
24
Q

What is the conversion rate to a higher grade Myelodysplasia?

A

20% convert to a higher grade Myelodysplasia
10% develop acute leukemia

25
Q

What is refractory cytopenia?

A

Rare condition of neutropenia or thrombocytopenia without increase in blasts in which drugs, chemicals and immune causes have been ruled out classify as Refractory Cytopenia.

Conversion to a more severe DMPS disease proves cause related to stem or progenitor cell defect.

26
Q

What is the main diagnostic requirement for Refractory Anemia with Ringed Sideroblasts?

A

> 15% ringed sideroblasts of all nucleated red cells in the marrow.

27
Q

What characteristics in cell changes does Refractory Anemia with Ringed Sideroblasts (RARS) have?

A
  1. Marrow demonstrates erythroid hyperplasia, megaloblastoid maturation.
  2. Minimal changes in the myeloid and megakaryocyte cell lines.
  3. Non-ringed sideroblasts show increase in iron and coarse iron granules
28
Q

What is seen in the peripheral blood in RARS?

A
  1. Dimorphic: Microcytic / hypochromic with oval macrocytes* (Dimorphism is a differentiating feature of RARS)
  2. Pappenheimer bodies can be seen in NRBC and non-nucleated RBC.
29
Q

What causes pappenheimer bodies in RBC’s?

A

Defective iron incorporation into the RBC during maturation.

30
Q

What can RARS transform into?

A
  1. Acute Leukemia (low # of patients)
  2. Transformation increased with multilineage dyspoiesis and cytogenetic abnormalities.
31
Q

What is the primary defect and differentiating features of Refractory Anemia with Excess Blasts?

A
  1. Primary defect is dysgranulopoiesis (but also seen in other DMPS).
  2. Differentiating features:
    a) Cytopenias of 2 out of 3 cell lines
    b) 5-20% blasts in the marrow.
  3. # of blasts in marrow supersedes all other features for classifying this DMPS.
32
Q

How many blasts in the peripheral blood in Refractor Anemia with Excess Blasts?

A

Up to 5%

33
Q

What is the state of erythroid cells and megakaryocyte cell lines in RAEB?

A
  1. Erythroid dysplastic features of RA and RARS exist in RAEB.
  2. Mononuclear and bilobed megakaryocytes may be present in the bone marrow.
  3. Large dysplastic platelets in peripheral blood.
34
Q

What are the differentiating features of Refractory Anemia with Excess Blast in Transformation (RAEBIT)?

A
  1. 5% or more blasts in peripheral blood.
  2. 20-30% blasts in bone marrow** (Main ID)
  3. Blasts may have auer rods.
35
Q

What does RAEBIT have in common with the other DMPS?

A

Cytopenias and cellular dyspoiesis of other Myelodysplastic Syndromes.

36
Q

What is the main differentiating feature for Chronic Myelomonocytic Leukemia (CMML)?

A

Leukocytosis with organ involvement (hepatosplenomegaly) and large numbers of monocytes.

37
Q

What is similar between CMML and the other DMPS conditions?

A

They similarly exhibit prominent dyspoiesis and specific cytopenias (anemia and thrombocytopenia).

38
Q

What are the diagnostic classification (FAB) for CMML?

A
  1. 0-20% blasts in the marrow, <5% in peripheral blood.
  2. > 20% monocytes in marrow.
  3. > 1x10^9/L monocytes in peripheral blood.
39
Q

What is special about the neutrophil cells in CMML?

A

Combination of cells with monocyte and myeloid features termed myelomonocytic cells make them difficult to differentiate.

40
Q

What can be used to differentiate myelomonocytic cells?

A

Combined dual esterase stain (alpha-napthal butyrate-chloracetate esterase stain) very helpful in differentiating these cells.

41
Q

What is Secondary or Therapy related syndrome?

A
  1. A DMPS not included in the FAB classification.
  2. Occurs following therapy to radiation and or chemotherapy.
  3. Nearly always pancytopenia.
42
Q

What is helpful to diagnosis Secondary or Therapy Related Syndrome?

A

Cytogenetic studies as high % have abnormal chromosomes 5 and 7 following radiation and chemotherapy.

43
Q

What is 5q- Syndrome?

A
  1. *Refractory Anemia with Megakaryocytic Abnormalities.
  2. Bone marrow is normocellullar or hypercellular. *Distinguishing features is small or medium sized mononuclear or bilobed megakaryocytes.
  3. Peripheral blood has oval macrocytes & normal or increased platelets.
  4. Cytogenetic disorder with deletion between bands q15 and q31 of long arm chromosome 5.
44
Q

What population are the majority of cases of 5q- Syndrome?

A

Women

45
Q

What can 5q- Syndrome transform to?

A

Frequent transformation to Acute Leukemia.

46
Q

What is the prognosis of DMPS?

A

Approx 2.5 years survival rate.
Patients can die with or without developing acute leukemia usually from complications of anemia, thrombocytopenia, and neutropenia.

47
Q

What is the chance of transformation of DMPS to Acute Myeloid Leukemia?

A

> 20% chance.

48
Q

What are useful laboratory tests for DMPS?

A
  1. CBC, blood film examination
  2. Bone marrow & biopsy examination very helpful.
  3. Serum B12 and Folate tests to differentiate Megaloblastic Anemia.
  4. Serum iron, ferritin levels along with iron stains on bone marrow aspirate should be performed to rule iron deficiency in the presence of a microcytic, hypochromic anemia.
  5. Reticulin and combined esterase stain (to help ID and quantitate cells).
  6. Cytogenetic studies (40-60% have similar abnormalities to AML, ID 5q- Syndrome, sometimes helps to differentiate CMML from CML).
  7. Immunophenotyping helpful in some cases.
49
Q

Which DMPS conditions is a blood film examination most helpful in diagnosing the condition? Where is it not sufficient and why?

A
  1. RAEB, CMML, and RAEBIT have features and greater dysplastic changes that a diagnosis can be made accurately with morphological evaluation.
  2. RA and RARS (esp RA) morphology alone cannot ID as B12 and folate deficiency can resemble RA.
50
Q

What is the follow-up and treatment for those diagnosed with DMPS?

A
  1. If stable - check ups at 6-12 months interval with CBC & differential.
  2. If change - bone marrow and cytogenetic studies may be performed to confirm imminent leukemic transformation.
  3. Supportive therapy in the form of transfusions.
  4. Chemotherapy and bone marrow transplantation only cure. Limited to patients <50 years of age.

Hematology 2 (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions