Clinical Pathology(Heme)

Front 1

The hemiglobin cyanide technique of measuring hemoglobin can detect all forms of hemoglobin, except:
A. methemoglobin
B. carboxyhemoglobin
C. deoxyhemoglobin
D. sulfhemoglobin
E. oxyhemoglobin

Back 1

D. sulfhemoglobin.
The hemiglobin cyanide technique involves oxidizing hemoglobin and converting it to hemiglobin cyanide, which is measured at an absorbance of 540nm. Almost all forms of hemoglobin, with the notable exception of sulfhemoglobin, can be measured in this fashion.
QCCP2, Measurement of total hemoglobin

Front 2

Which of the following values is calculated from red blood cell indices in an automated red blood cell count?
A. red blood cell count (RBC)
B. hematocrit
C. mean corpuscular volume (MCV)
D. red cell distribution width (RDW)
E. total hemoglobin

Back 2

B. hematocrit.
Red cell counts are measured by the Coulter principle, which states the pulse in voltage that occurs when a cell passes through a current is proportional to the volume of the cell. The range of volumes is the RDW; the mean is the MCV. From the MCV and the RBC count, the hematocrit can be calculated (hematocrit = MCV × RBC).
QCCP2, Automated techniques

Front 3

For the automated counting of leukocytes by the Coulter principle, what is usually done to the blood sample?
A. filtering out red blood cells
B. lysis of red blood cells
C. clumping agent added to remove platelets
D. sample is clotted
E. leukocytes selectively filtered before counting

Back 3

B. lysis of red blood cells.
Because the volume of red blood cells and leukocytes is very similar, and the Coulter principle technique counts cells as a function of their volume, RBCs and WBCs are counted as one. In RBC counts, it's usually not a problem because there are a lot more red blood cells than white blood cells and red blood cells are lysed to count the white cells.
QCCP2, Leukocyte indices

Front 4

Which leukocyte has the highest side scatter?
A. monocytes
B. neutrophils
C. basophils
D. eosinophils
E. lymphocytes

Back 4

D. eosinophils.
Side scatter is a measurement of cytoplasmic granularity or complexity. Eosinophils present with the highest level of side scatter due to the crystalline inclusions.
QCCP2, Flow cytometry

Front 5

Where is the platelet window as counted by electrical impedance?
A. 1-2 fL
B. 2-20 fL
C. 20-50 fL
D. 30-36 fL
E. 36-360 fL

Back 5

B. 2-20 fL.
Smaller than red blood cells and leukocytes, platelets can be quantitated by the Coulter method, too. From this it is evident why schistocytes (fragmented red blood cells) can present as an artefactually high platelet count and platelet clumping or large platelets can lead to a low platelet count.
QCCP2, Platelets

Front 6

What feature of reticulocytes is the most helpful in distinguishing them from mature red blood cells?
A. size
B. shape
C. color
D. RNA
E. DNA

Back 6

D. RNA.
Residual ribosomal RNA characterizes reticulocytes which can be demonstrated with supravital staining (crystal violet or methylene blue). Reticulocytes tend to be larger than mature red cells. However, this is not as dependable an index of reticulocytes as RNA.
QCCP2, Reticulocytes

Front 7

Which feature of a reticulocyte is most helpful at determining its age?
A. presence/absence of a nucleus
B. RNA content
C. enumeration of ribosomes
D. presence/absence of mitochondria
E. presence/absence of Golgi bodies

Back 7

B. RNA content.
Reticulocytes are non-nucleated. And while ribosomes, mitochondria, and Golgi bodies are often present in reticulocytes, it is the RNA content that best assists with determining its age.
QCCP2, Reticulocytes

Front 8

For which of the following hematocrits is the correction factor = 3.0 for calculating the reticulocyte proliferation index?
A. 40%
B. 30%
C. 15%
D. 5%
E. 2%

Back 8

C. 15%.
I don't even want to think of hematocrits of 5% or 2% - they are surely incompatible with life. The correction factor is a means of standardizing the reticulocyte count when calculating the proliferation index (RPI). As the hematocrit drops, younger reticulocytes with a longer maturation time are released, which could give an artefactually high RPI. As hematocrit drops, the correction factor increases, so that at a hematocrit of 15, the correction factor is 3.0, and at a hematocrit of 30, the correction factor is 2, and with a normal hematocrit, the correction factor is one.
QCCP2, Reticulocytes

Front 9

In the hemoglobin solubility (dithionate) test, which form(s) of hemoglobin cause(s) turbidity (positive reaction)?
A. HbSS
B. HbSC
C. HbSA
D. A & B
E. A, B, C

Back 9

E. A, B, C.
Almost any sickling hemoglobin in any combination can lead to a positive result - SS, SA, SC, etc - including CHarlem. It is important to ensure there is sufficient HbS in order for the test to be positive.
QCCP2, Detection of normal and variant hemoglobins

Front 10

Which of the following patterns of eosinophilia in the acid elution test for detection of fetal hemoglobin is most consistent with hereditary persistence of fetal hemoglobin?
A. heterocellular
B. pancellular
C. centrocellular
D. paucicellular
E. acellular

Back 10

B. pancellular.
This is true for the most part. Since almost all cells would be affected by persistence of fetal hemoglobin, it could be demonstrated to be present in almost all cells. Other conditions, such as sickle cell disease or thalassemia associated with increased hemoglobin F, have a heterocellular distribution of fetal hemoglobin.
QCCP2, Detection of fetal hemoglobin

Front 11

Which pair of hemoglobin variants cannot be resolved with hemoglobin electrophoresis on cellulose acetate at pH 8.6?
A. HbS, HbD
B. HbS, HbA
C. HbA, HbF
D. HbC, HbS
E. HbG. HbF

Back 11

A. HbS, HbD.
Alkaline electrophoresis is unable to distinguish (resolve) between HbS, HbD, and HbG. Electrophoresis under acidic conditions allows for the resolution of HbS from HbD and HbG (which are still not resolved between each other. I use an easy two-step method to read hemoglobin electrophoretic gels:
1. align gels with positive electrodes together, alkaline on the left.
2. utilize mnemonics to remember band migration:
Alkaline gel - from left, the bands: “A2 CEO, Save me Dear God From Anemia. Bart goes to the NIH” HbA2, HbC, E, O; HbS, D, G; HbF; HbA; HbBarts; HbN, I, H.
Acidic gel - from the left: “Crazy Sick AGED Father” - HbC; HbS; HbA, G, E, D; HbF
QCCP2, Hemoglobin electrophoresis, F4.2b

Front 12

Which of the following are consistent with the diagnosis of beta-thalassemia?
A. increased red blood cell
B. low MCV
C. decreased HbA2
D. A & B
E. A, B, C

Back 12

D. A & B. Due to a decrease in HbA (2 alpha and 2 beta chains) from making less beta globin, there is a relative increase in HbA2. The other findings are considered “thalassemic indices,” alpha thalassemia differs in that the HbA2 is normal.
QCCP2, Hemoglobin electrophoresis

Front 13

Which of the following hemoglobins is routinely quantified by HPLC? (Choose all possible answers)
A. HbS
B. HbA
C. HbA2
D. HbC
E. HbF

Back 13

C. HbA2.
E. HbF.
They are the only hemoglobins that the FDA has approved for quantitation by HPLC.
QCCP2, HPLC

Front 14

Which of the following chemicals are present in Wright stain?
A. eosin
B. methylene blue
C. alcohol
D. A & B
E. A, B, C

Back 14

E. A, B, C.
Eosin stains the red blood cells. Nucleic acids are stained by the basic methylene blue. Stain tint varies with pH.
QCCP2, Histochemical and cytochemical

Front 15

What type of leukocytes are stained by Sudan black B?
A. granulocytes
B. monocytes
C. lymphocytes
D. A & B
E. A, B, C

Back 15

D. A & B.
While myeloperoxidase and chloracetate esterase (CAE) are fairly specific for granulocytes, Sudan black B can stain granulocytes and monocytes.
QCCP2, Cytochemical stains for typing blasts

Front 16

Which of the following cell types is predominantly stained by non-specific esterases (alpha naphthyl acetate esterase and alpha naphthyl butyrate esterase) and is inhibited by sodium fluoride?
A. monocytes
B. megakaryocytes
C. lymphocytes
D. granulocytes
E. erythrocytes

Back 16

A. monocytes.
While all of the mentioned cell types can be stained to a variable extent by NSE, monocytes are the most consistently stained and the only cell type whose staining is inhibited by sodium fluoride.
QCCP2, Cytochemical stains

Front 17

Which of the following description best fits the method of determining leukocyte alkaline phosphatase (LAP) score?
A. the sum of scoring of 100 monocytes, lymphocytes, and granulocytes 0 to 4+ based on intensity of LAP staining
B. the sum of scoring of 100 monocytes and lymphocytes 0 to 4+ based on intensity of LAP staining
C. the sum of scoring of 100 eosinophils 0 to 4+ based on intensity of LAP staining
D. the sum of scoring of 100 bands and polymorphonuclear cells 0 to 4+ based on intensity of LAP staining
E. the sum of scoring of 100 lymphocytes 0 to 4+ based on intensity of LAP staining

Back 17

D. the sum of scoring of 100 bands and polymorphonuclear cells 0 to 4+ based on intensity of LAP staining.
The leukocyte alkaline phosphatase (LAP) score is a quantitative means of assessing the differential diagnosis of a high white blood cell count. Normal values fall in the 50-150 range. Low LAP scores are found in chronic myelogenous leukemia and paroxysmal nocturnal hemoglobinuria, while high LAP scores are seen with leukemoid (reactive) reaction, myeloproliferative disorders (other than CML), and steroid administration.
QCCP2, LAP

Front 18

Why is it important to use fluorochromes that absorb light at one wavelength and emit at another wavelength in flow cytometry?
A. the intensity of light at the original wavelength in flow cytometry
B. for simultaneous analysis of cell size and complexity
C. the change in wavelength and consequently color indicates the velocity of the particle
D. the original wavelength used is not at a detectable wavelength
E. the shift in wavelength allows for greater particle resolution

Back 18

B. for simultaneous analysis of cell size and complexity.
As light passes through the single cell flow counter, it excites the fluorochrome while simultaneously being refracted to an extent based on the characteristics of the cells passing through. The refracted light information is at the original wavelength and, depending on the position of the detector, represents cell size (forward scatter) or cytoplasmic complexity (side scatter). At the same time, a third detector determines the intensity of fluorochrome emittance (at a different wavelength).
QCCP2, Flow cytometry

Front 19

. Which of the following stains expressed by pre-B cells are typically lost in B cells?
A. TdT
B. CD34
C. HLA-DR
D. A & B
E. A, B, C

Back 19

D. A & B.
The pro-B cell stage still retains some of the rudimentary stem cell markers while undergoing heavy chain rearrangement, the pre-B cells tend to lose TdT and CD34, but retain HLA-DR.
QCCP2, Expected phenotypes of hematopoietic cells

Front 20

Which of the following B cell markers is expressed along with IgM expression?
A. CD19
B. CD34
C. TdT
D. CD38
E. CD10

Back 20

A. CD19.
CD19 is one of the most consistent B lymphocyte markers, present in all immature B cells and finally lost in the development of plasma cells.
QCCP2, T4.2 B and T cell maturation stages

Front 21

What is the normal peripheral blood and tissue ratio of T to B cells?
A. 1:5
B. 1:10
C. 3-4:1
D. 10:1
E. 100:1

Back 21

C. 3-4:1.
The mantra “3-4:1” will support you through much of hematopathology. It is also the ratio of CD4 to CD8 T cells and the ratio of kappa:lambda in normal B cells.
QCCP2, B lymphocytes

Front 22

The surface expression pattern of CD3 follows the surface expression of this other T cell marker:
A. CD2
B. TdT
C. CD34
D. T cell receptor
E. CD4

Back 22

D. T cell receptor.
CD3 expression in less mature T cells is restricted to the cytoplasm. With progressive maturation, cytoplasmic CD3 expression is lost while surface CD3 expression is seen. The appearance of CD3 on the surface is coincident with the expression of T cell receptor on the cell surface where it is noncovalently associated with CD3.
QCCP2, T lymphocytes

Front 23

In which of the following locations are gamma-delta T cells most commonly found?
A. spleen
B. dermis
C. intestine
D. A & B
E. A, B, C

Back 23

E. A, B, C.
While the vast majority of T cells are of the alpha beta subtype, there are significant numbers of gamma delta T cells found in the spleen, dermis, and intestine - which are also the most common sites of gamma delta T-cell lymphoma.
QCCP2, T lymphocytes

Front 24

All of the following neoplasms express high levels of bcl-6, except:
A. nodular sclerosis Hodgkin lymphoma
B. Burkitt lymphoma
C. follicular lymphoma
D. nodular lymphocyte-predominant Hodgkin lymphoma
E. t(3;14) diffuse large B-cell lymphoma

Back 24

A. nodular sclerosis Hodgkin lymphoma.
The normal expression of bcl-6 is confined to normal germinal center B cells. It can also be expressed in a number of malignancies, aiding in diagnosis.
QCCP2, Immunophenotyping

Front 25

All of the following cells express CD1a, except:
A. Langerhans cells
B. Touton giant cells
C. dendritic reticular cells
D. interdigitating reticulum cells
E. cortical thymocytes

Back 25

B. Touton giant cells.
While CD1a expression is usually thought to be associated with Langerhans' cells, it is important to note that its expression is not limited to Langerhans cells. A common mistaken diagnosis for Langerhans histiocytosis is thymoma, due to the misinterpretation of a positive CD1a stain.
QCCP2, Immunophenotyping

Front 26

Which of the following T-cell phenotypes is most likely to be associated with a neoplasm?
A. CD4+/CD8-
B. CD4-/CD8+
C. CD4+/CD8+
D. CD4-/CD8-
E. all of the above are normal phenotypes

Back 26

D. CD4-/CD8-.
Choices A and B are the T cells we typically think of in the peripheral blood (remember “3-4:1” CD4+ to CD8+ cells). In the thymic cortex it is not unusual to have immature CD4+/CD8+ cells. CD4-/CD8- cells are abnormal and are most often associated with a neoplastic condition.
QCCP2, Immunophenotyping

Front 27

In which of the following types of cells is CD5 usually expressed?
A. mature T cells
B. small lymphocytic lymphoma/chronic lymphocytic leukemia
C. rheumatoid arthritis
D. A & B
E. A, B, C

Back 27

E. A, B, C.
Benign polyclonal CD5+/CD19+/CD20+ B cells can be seen associated with several conditions, including rheumatoid arthritis. In addition, normal mature T-cells often express CD5, but it can be lost in T cell leukemia or lymphoma. Of course, several mature B cell neoplastic conditions, such as CLL/SLL and mantle cell lymphoma, are associated with CD5 expression.
QCCP2, Immunophenotyping

Front 28

Leu-M1 expression is commonly seen in all of the following, except:
A. Reed-Sternberg cells
B. mature monocytes
C. anaplastic large cell lymphoma hallmark cells
D. most adenocarcinomas
E. granulocytes

Back 28

C. anaplastic large cell lymphoma hallmark cells.
Leu-M1 or CD15 is a widespread antigen expressed in a number of tissues. Classically, the differential diagnosis between Hodgkin lymphoma and ALCL, which are both usually CD30+, is resolved with CD15+ in Hodgkin lymphoma, but not ALCL.
QCCP2, Immunophenotyping

Front 29

What is the typical CD20 staining pattern in chronic lymphocytic leukemia?
A. strong and diffuse
B. dim
C. absent
D. cytoplasmic restriction
E. nuclear

Back 29

B. dim.
Characteristically, the CD20 staining pattern is dim in CLL/SLL. A specific antigen on the CD20 cell surface marker is recognized by FMC-7. In cases of dim CD20, FMC-7 is typically negative, while other mature B cell neoplasms which have bright CD20 expression (and positive) FMC-7.
QCCP2, Immunophenotyping

Front 30

Which of the following surface markers is the IL-2 receptor?
A. CD20
B. CD21
C. CD23
D. CD25
E. CD30

Back 30

D. CD25.
CD25 is a marker of activated T and B cells as well as certain neoplasms, such as hairy cell leukemia and adult T cell leukemia/lymphoma. Adult T cell leukemia is of particular interest because it is associated with elevated soluble IL-2 receptor. CD20 is a B cell marker, CD21 is the receptor for EBV, and CD23 is the IgE receptor. CD30 or Ki-1 is expressed on normal plasma cells and immunoblasts, as well as several neoplastic cells, such as Hodgkin Reed-Sternberg, anaplastic large cell lymphoma hallmark cells, embryonal carcinoma, and some subtypes of diffuse large B-cell lymphoma (particularly mediastinal).
QCCP2, Immunophenotyping