MALIGNANT LEUKOCYTE DISORDERS Flashcards
What acute leukemia cellular morphology is most often associated with Disseminated Intravascular Coagulation (DIC)?
Blast-like cells with butterfly, reniform nuclear shapes and abundant auer rod
According to the WHO classification, what is the minimal percentage of blasts required in bone marrow to confirm a diagnosis of acute leukemia?
20%
Which cell line will demonstrate a diffuse positive reaction for a non-specific esterase α-Naphthyl acetate stain?
Monocytic
According to the FAB classification, which leukemia demonstrates end-stage maturation at the promyelocyte stage with Faggot Cells?
M3
Which of the following bone marrow disorders is best characterized by a peripheral blood smear showing immature granulocytes, nucleated NRBCs, tear drop RBCs and large and giant platelets?
Myelofibrosis
What unique chimeric gene is found in Chronic Myeloid Leukemia?
BCR-ABL1
Which cytochemical stains are useful in differentiating AML from ALL?
SBB
Which leukemia accounts for up to 75% of childhood leukemia?
Acute lymphocytic leukemia
What is the greatest transformational risk associated with the Myelodysplastic Syndromes?
Acute Leukemia
How much of the nucleus must iron granules circle in order to be considered a ringed sideroblast?
At least 1/3 of the nucleus
Why is it important to perform Pearl’s Prussian blue stain on a bone marrow aspirate smear?
To differentiate Iron Deficiency from Sideroblastic anemia
What special stain would be used to differentiate CML from a leukemoid reaction?
LAP
What genetic mutation is associated with Polycythemia Vera?
JAK2 gene
Which of the following will demonstrate a negative MPO staining reaction?
M0
Why is a bone marrow biopsy of the utmost importance in the diagnosis of Hairy Cell Leukemia?
The aspirate is a dry tap
What best describes the morphology of typical CLL lymphocytes?
Small round lymphocytes with a soccer ball pattern
What is present in patients with Multiple Myeloma?
Hypercalcemia, increased plasma cells, increased Monoclonal Immunoglobulin
What is a distinct morphological difference between Lymphoblasts and Myeloblasts?
Auer Rods
What is the definition of M/E ratio?
Myeloid:Erythroid ratio
In flow-cytometry, what does CD stand for?
Cluster of Differentiation
What auxiliary tests are routinely collected during a bone marrow aspiration?
Cytogenetics, Immunology (Flow) & Molecular
What does cytogenetics testing do?
Identifies the type of AML, and gives specific gene translocation.
What does immunology (flow) testing do?
Identifies the type of blasts – Myeloid vs.Lymphoid, Type of lymphocytes (B-Cell, T-Cell, can differentiate CLL from NHL)
What does molecular testing test for?
Bcr/Abl1(Philadelphia Chromosome)
What is the significance of Auer rods and what cells are they found in?
Auer rods indicate an AML and are found in Myeloblasts and abnormal promyelocytes
What is the name of a mature red cell that contains iron?
Siderocyte
What is a nucleated red cell that contains iron called?
Sideroblast
- What genetic translocation is found in M3?
t(15;17)
- What is the genetic translocation found in CML?
t(9;22)
Name 3 abnormal features of cells seen in Myelodysplastic syndrome.
- Hypogranulation
- Hypolobation
- Nuclear-cytoplasmic dissociation
What is the principle of LAP stain?
- Substrate naphthol AS-B1 phosphate is hydrolyzed by the LAP enzyme found in secondary neutrophil granules at an alkaline PH which combines w red dye to produce a color precipitate proportional to the amount of enzyme present.
What is the principle of PAS?
Periodic acid oxidizes glycogen, mucoproteins, and HMW carbohydrates to aldehydes which react with colorless Schiff reagent to stain bright pink. Intensity and pattern depend on the aldehyde groups present.
What does PAS differentiate?
Differentiate certain Lymphoid and abnormal erythroid cells(as in AML M6)
What are the results for Sudan Black B?
AML(+) vs ALL(-)
AML M0 and pure monocytic AML may also be(-)
What does SBB stain?
stains lipids, the intensity of the staining is dependent on the amount of lipids present and the maturity of the cell.
What is the principle of the Tartrate Resistant Acid Phosphatase (TRAP) stain?
Acid phosphatase hydrolyzes the substrate naphthol AS-B1 phosphoric acid and couples with a dye to produce a red precipitate.
Hairy cells produce an abundance of isoenzyme 5.
What do esterases – SE (Specific) & NSE(Nonspecific) differentiate?
Used to differentiate myeloblast and neutrophils from monocytic.
