Hematology ASCP
How is the Mean Cell Volume calculated? A) (Hemoglobin / Red blood cells) X 10 B) (Hemoglobin / Red blood cells) X 100 C) (Hematocrit %/ Red blood cells) X 10 D) (Hematocrit % X Hemoglobin) X 100
C) (Hematocrit %/ Red blood cells) X 10 The Mean Cell Volume, or the MCV, can be calculated by dividing the hematocrit (%) by the red blood cell count and multiplying by 10. The MCV describes the volume, or size, of the red blood cell population. The Mean Cell Hemoglobin, or the MCH, can be calculated by dividing the hemoglobin (g/dL) by the red blood cell count and multiplying by 10. The MCH represents the average weight of hemoglobin in red blood cells. The Mean Cell Hemoglobin Concentration, or the MCHC, can be calculated by dividing the hemoglobin (g/dL) by the hematocrit (%) and multiplying by 100. The MCHC is the ratio of hemoglobin mass to volume of red blood cells.
What is the normal cellularity of an iliac crest bone marrow biopsy in a 50-year-old male: A) 20% B) 35% C) 50% D) 65%
C) 50% A general estimate of the expected normal cellularity range in an adult can be determined by first subtracting the age of the patient from 100%. The range is then +/- 10 of that number. Therefore, a normal, healthy 50-year-old should have an overall cellularity between 40% and 60%. Note that the iliac crest is the preferred site for bone marrow collection in adult.
If a Mycobacterium sp. infection is suspected on a bone marrow or body fluid, what stain should be used to detect these bacteria? A) Wright's stain B) New methylene blue stain C) Hematoxylin and Eosin (H&E) stain D) Acid fast stain
D) Acid fast stain Mycobacteria have thick waxy cell walls, which do not stain with most stains. An acid-fast stain such as Ziehl-Neelsen or Kinyoun should be used because the heat and/or the acid allow the stain to penetrate the cell walls. The Wright's stain is useful for many hematological examinations, but because it cannot penetrate the cell walls of Mycobacteria, it is not useful for this procedure. New methylene blue stain is a vital stain used to visualize organelles such as ribosomes in reticulocytes but is not useful for Mycobacteria detection. Hematoxylin and eosin stain is used for standard bone marrow exam it is not useful in this case.
Warfarin (coumarin-type anticoagulant) inhibits all the following coagulation factors except: A) Factor II B) Factor IX C) Factor VII D) Factor XI
D) Factor XI Warfarin (coumarin-type oral anticoagulant) only inhibits vitamin K dependent factors, Factors II, VII, IX, and X, and proteins C, S, and Z. Factor XI is not vitamin K dependent.
Laboratory tests which distinguish Polycythemia Vera (PV) from Chronic Myelogenous Leukemia (CML) include all of the following EXCEPT: A) The JAK 2 mutation B) Nucleated red blood cells C) Elevated LAP score D) Hypercellular bone marrow
D) Hypercellular bone marrow Both CML and PV are characterized by hypercellular bone marrow due to unchecked proliferation, so this is not a distinguishing test. The JAK 2 mutation is found in most cases of PV but not in CML Many nucleated RBCs can be seen in CML but are rare in PV. The LAP score in CML is typically decreased, whereas the LAP score in PV generally is slightly increased.
A patient admitted to the hospital for ongoing fever produces the following laboratory results: RBC count: 3.56 x 1012/L WBC count: 57.5 x 109/L Platelet count: 375,000/uL Differential count: 3 blasts, 10 myelocytes, 6 metamyelocytes, 12 bands, 64 segs, 4 lymphocytes, and 1 monocyte LAP score = 155. Which of the following conditions correlates closely with this patient's results? A) Leukemoid Reaction B) Chronic Myelogenous Leukemia C) Genetic translocation (9;22)(q34;q11) D) Paroxysmal Nocturnal Hemoglobinuria
A) Leukemoid Reaction A high white blood cell count, usually 50-100 x 109/L with a left shift, is a common finding in leukemoid reactions. In addition, a key feature of a leukemoid reaction is a high LAP score. Chronic Myelogenous Leukemia (CML) is highly associated with the Philadelphia chromosome or translocation (9;22)(q34;q11). CML typically shows a low LAP score, in contrast to the findings in this case. Finally, Paroxysmal Nocturnal Hemoglobinuria (PNH) is also associated with a low LAP score, which excludes this as the correct answer.
What drug may be used to decrease iron levels in patients with iron overload? A) Desferrioxamine B) Cobalamin C) Antibiotics D) Eculizumab
A) Desferrioxamine Desferrioxamine (DFO), an iron-chelating agent, may be used to reduce iron overload in patients who rely on transfusions to maintain hemoglobin levels and prevent anemia. Cobalamin is the chemical name for Vitamin B12 and is the treatment of choice in megaloblastic anemia related to B12 deficiency. Antibiotics would be of no use in the treatment of iron overload. Eculizumab is the drug of choice in the treatment of classic PNH. It is a humanized monoclonal antibody that inhibits complement lysis.
Which of the following is necessary for the absorption of Vitamin B12: A) Intrinsic factor B) Folic acid C) Gastrin D) Insulin
A) Intrinsic factor Intrinsic factor is necessary for the proper absorption of vitamin B12. With a deficiency of intrinsic factor, individuals can develop megaloblastic anemia if their bodies become deficient in vitamin B12, which plays a large role in cellular nuclear development.
The life span of RBCs containing Hemoglobin H is typically: A) Less than 120 days B) 100-120 days C) 120-140 days D) Greater than 140 days
A) Less than 120 days The normal lifespan of RBCs is 120 days. The life span of an RBC containing Hemoglobin H inclusions is significantly decreased because the RBC membrane is compromised when macrophages attempt to remove this unstable hemoglobin, which is precipitated just inside the membrane. This results in a moderate hemolytic anemia with decreased RBC survival.
Laboratory results obtained on a 47-year-old patient were as follows: WBC 51.2 x 103/µL RBC 4.27 x 106/µL HGB 12.6 g/dL HCT 36.9% PLT 403 x 103/µL Differential: 50% segmented neutrophils 20% bands 12% lymphocytes 7% monocytes 1% eosinophils 9% metamyelocytes 1% myelocytes RBC morphology: normocytic, normochromic WBC morphology: moderate toxic granulation, slight Dohle body Which test would be MOST helpful in establishing a diagnosis in this case? A) Leukocyte alkaline phosphatase stain (LAP stain) B) Nonspecific esterase stain C) Acid phosphatase D) Sudan black B
A) Leukocyte alkaline phosphatase stain (LAP stain) The LAP stain is used to determine if an increase of cells is due to Chronic Myelogenous Leukemia or a leukemoid (noncancerous) reaction such as an infection. Cells from a leukemoid reaction stain positive with many intense blue granules, while cells from chronic myelogenous leukemia have few blue granules. Although chromosomal studies are generally used to distinguish CML based on the Philadelphia chromosome, the LAP stain is still a reliable method to distinguish leukemoid reaction. Esterase stains are used in detecting monocytes, macrophages, and histiocytes and are not helpful in distinguishing cells in the neutrophilic line. Acid phosphatase stains are useful in distinguishing lymphocytes from other mononuclear cells. Sudan back B is useful in distinguishing cells in the myeloid line from those in the lymphoid line.
Adult (normal) Hemoglobin is made up of the following composition: A) >90% HbA, 1% HbA2, 5% HbF B) >95% HbA, <3.5% HbA2, <1-2% HbF C) <90% HbA, 10% HbA2, 5% HbF D) >90% HbA, 1% HbA2, 5-10% HbF
B) >95% HbA, <3.5% HbA2, <1-2% HbF Greater than 95% HbA is the correct answer here. Adult Hemoglobin is made up predominantly of HbA with only small amounts (< 1-2 %) of HbF (fetal hemoglobin) and HbA2 (1.5-3.7%). Normally, HbF (fetal hemoglobin) decreases to adult level (<2%) by about 6 months of age, although slight elevation may persist for 2 years. Decreased HbA, with a concomitant increase in HbA2 and HbF levels, are typically seen in ß-thalassemia. Retention of elevated levels of HbF (15% to 30% of total hemoglobin) is termed hereditary persistence of fetal hemoglobin (HPFH).
Which of the following leukemias can be excluded as a possible diagnosis if Auer rods are seen in blasts on the peripheral blood smear? A) Acute myelomonocytic leukemia B) Acute lymphoblastic leukemia C) Acute myeloid leukemia without maturation D) Acute promyelocytic leukemia
B) Acute lymphoblastic leukemia Auer rods are not seen in acute lymphoblastic leukemia. Auer rods are reddish-purple staining needlelike inclusions most commonly found in the cytoplasm of myeloblasts, as seen in various subgroups of acute myeloid leukemia. They are rarely seen in monoblasts and differentiated myelocytic cells. Auer rods are formed from the fusion of primary granules and are helpful in differentiating acute myeloid leukemia from acute lymphoblastic leukemia.
In almost all cases of polycythemia vera, which of the following genetic abnormalities is present? A) Philadelphia chromosome B) JAK2 mutation C) BCR/ABL1 D) t(15:17)(q22;q12)
B) JAK2 mutation The JAK2 mutation is present in over 95% of cases of polycythemia vera. This mutation causes a mutated tyrosine kinase activator.The Philadelphia chromosome is found in the majority of cases of chronic myelogenous leukemia.BCR/ABL1 is a fusion gene and is associated with the Philadelphia chromosome and chronic myelogenous leukemia.t(15:17)(q22;12) refers to the abnormality found in acute promyelocytic leukemia, also referred to as AML with t(15;17)(q22;12).
Esterase stains are used to help differentiate which of the following? A) Myeloblasts from lymphoblasts B) Monoblasts from myeloblasts C) Monoblasts from lymphoblasts D) Erythroblasts from lymphoblasts
B) Monoblasts from myeloblasts The esterase stains are used to differentiate monoblasts from myeloblasts. Myeloperoxidase (MPO) and Sudan black B (SBB) are used to differentiate myeloblasts from lymphoblasts.
What is the composition of Howell-Jolly bodies? A) Iron B) Wright stain precipitate C) DNA D) RNA
C) DNA Howell-Jolly bodies are composed of DNA. Howell-Jolly bodies are thought to be nuclear remnants or aggregates of chromosomes that have separated from the mitotic spindle and remain behind after the RBC nucleus is expelled. Howell-Jolly bodies do not contain iron. Pappenheimer bodies contain iron. Reticulocytes contain residual RNA, which may give the cells a bluish coloration (polychromasia) with Wright's stain.
Platelets are: A) The smallest nucleated cells seen in normal peripheral blood. B) The largest nucleated cells seen in normal peripheral blood. C) Fragments of megakaryocyte cytoplasm and do not contain nuclei D) Fragments of neutrophils
C) Fragments of megakaryocyte cytoplasm and do not contain nuclei Platelets do not contain nuclei. They are fragments of megakaryocyte cytoplasm. Therefore, they are not the smallest nor the largest nucleated cells found in peripheral blood. Neutrophils do not produce platelets.
The principle of most commercially available d-dimer assays is: A) Measuring the time it takes a patient's clot to lyse and form d-dimers B) Measuring plasminogen levels C) Using specific antisera to detect d-dimers' neo-epitopes D) Adding thrombin to patient plasma and measuring the time it takes to clot
C) Using specific antisera to detect d-dimers' neo-epitopes The correct answer is using specific antisera to detect d-dimers' neo-epitopes. Many different methods are available to do this, including a microplate ELISA, semi-quantitative latex agglutination, and others. Measuring clot lysis time would not be an assay for d-dimer. Plasminogen levels would reflect the ability of the patient to lyse clots but would not measure d-dimers or reflect the fact that the patient is forming clots. Adding thrombin to patient plasma is a thrombin time assay and measures fibrinogen levels.
The following results correlate with which of the following myelodysplastic syndromes? 2 cyotpenias in the peripheral blood 11% blasts in the peripheral blood 18% blasts in the bone marrow Auer rods present A) MDS-EB-2 B) MDS-SLD C) MDS-MLD D) MDS-U
A) MDS-EB-2 These results are consistent with Myelodysplastic Syndrome (MDS) with excess blasts subtype 2 (MDS-EB-2). In the peripheral blood of a case of MDS-EB2 you would expect to see 1-3 cytopenias and between 5 and 19% blasts. In the bone marrow of cases of MDS-EB2, you would expect to see 0 to 3 dysplastic lineages and between 10 and 19% blasts. Patients with Auer rods are classified as MDS-EB-2. MDS with single lineage dysplasia (MDS-SLD) have no or rare blasts in their peripheral blood with less than 5% blasts in the bone marrow. MDS with multilineage dysplasia (MDS-MLD) and MDS, unclassified (MDS-U) present with no or rare (<1%) blasts in the peripheral blood.
A few dark blue staining granular inclusions located near the periphery of an erythrocyte are most likely: A) Pappenheimer bodies B) Howell-Jolly bodies C) Heinz bodies D) Basophilic stippling
A) Pappenheimer bodies Pappenheimer bodies appear as blue/purple cytoplasmic inclusions found in the periphery of red blood cells. Pappenheimer bodies are composed of iron and protein and can be found in various conditions including sideroblastic anemia. Howell-Jolly bodies are blue-purple DNA fragments. Heinz bodies are precipitated unstable hemoglobin visible with supravital stains. In basophilic stippling, there are multiple dark purple precipitated RNA.
A patient has a hypercellular bone marrow and is suspected of having a myeloproliferative disorder. Laboratory features include: excess megakaryocyte proliferation and atypia, marked marrow fibrosis, and the JAK2 mutation. The most likely diagnosis is: A) Primary Myelofibrosis (PMF) B) Chronic Myelogenous Leukemia (CML) C) Chronic Neutrophilic Leukemia (CNL) D) Essential Thrombocythemia (ET)
A) Primary Myelofibrosis (PMF) The listed features are all diagnostic of PMF. The megakaryocyte proliferation and marrow fibrosis are most characteristic. CML does not have the JAK 2 mutation and has excess proliferation in many of the myelocytic lines. CNL is characterized by neutrophilia and the CSFR mutation. ET has excess megakaryocyte proliferation and the JAK2 mutation, but platelet counts are higher. Also, though there can be some fibrosis, it is not as characteristic or excessive as in PMF.
Methods of identifying many of the major hemoglobin variants such as Hb A, Hb F, Hb S, etc. include all of the following EXCEPT: A) Sodium metabisulfite solubility test B) High performance liquid chromatography (HPLC) C) Citrate agar electrophoresis D) Alkaline electrophoresis
A) Sodium metabisulfite solubility test The correct answer is the sodium metabisulfite solubility test which is useful only as a screening tool for fetal hemoglobin (HbF). When blood containing HbF is added to the sodium metabisulfite solution, it will precipitate and produce a cloudy solution compared to normal Hb A, which results in a clear solution. HPLC is the newest and most rapid method of identifying many hemoglobin variants. This is a method of separating the hemoglobin proteins by pumping them in a solvent at high pressure through a column with chromatographic packing. Citrate (acid) and alkaline agar electrophoresis can separate the hemoglobin variants according to size and electrical charge. The resulting bands migrate differently on acid and alkaline agars.
If a sodium citrate sample drawn for coagulation is noted to be filled an inch below the fill line (black line), then the specimen is considered: A) Unacceptable for coagulation studies B) Acceptable for coagulation studies C) Acceptable if the tube can be filled with additional blood D) Acceptable if only the PT test is to be performed
A) Unacceptable for coagulation studies In any coagulation testing, the sodium citrate tubes MUST be filled to the black line, meaning properly filled, to ensure the proper ratio of blood to anticoagulant inside of the tube; which should be 9:1. If the tube is not filled adequately, the specimen must be not be used for testing and a redraw should be requested. An excess of anticoagulants can alter the expected dilution of blood and produce errors in the results.
Cooley's anemia is another name for which form of beta-thalassemia? A) Delta-beta thalassemia B) Beta thalassemia major C) Beta thalassemia intermedia D) Beta thalassemia minor
B) Beta thalassemia major Cooley's anemia is another name for beta-thalassemia major. Clinical symptoms usually develop during an affected child's first year of life. The child appears to be malnourished and may exhibit abdominal girth expansion. Skeletal deformations are evident, which are a result of increased erythropoiesis. A common finding is facial bone changes. Other clinical signs include frequent infections, hepatomegaly, splenomegaly, cardiomegaly, gall stones, leg ulcers, and poor growth and sexual development. Death usually occurs by the time these patients are in their early twenties unless treated with blood transfusions along with iron-chelating agents.
The light blue-gray inclusions observed in the cytoplasm of many of the bands and segmented neutrophils of a burn patient are most likely? A) Auer rods B) Dohle bodies C) Toxic granules D) May-Hegglin bodies
B) Dohle bodies The correct answer here is Dohle bodies. Dohle bodies are associated with the peripheral smears of burn patients, severe infections, and cancer as a result of toxic drugs used on the patients. Auer rods are found in myeloblasts, not bands or neutrophils. Toxic granules can be found in many conditions, especially infections. Toxic granules have a stippling appearance, which does not have the appearance as described in the question. May-Hegglin bodies are found in May-Hegglin anomaly, which is a white cell disorder. May-Hegglin bodies are very similar in appearance to Dohle bodies.
The most specific test to detect both presence of Factor V Leiden, also known as activated protein C resistance (APC) and predict risk of thrombosis is: A) Activated Protein C Resistance (APC) clot-based assay B) Factor V Mutation Assay C) ELISA assay for Factor V D) Antithrombin antigen assay
B) Factor V Mutation Assay The Factor V Mutation Assay is a molecular test to detect the inherited mutated gene for Factor V resistance to activated protein C. It is also useful to predict risk of thrombosis in that heterozygotes have lower risk than someone who inherits two copies (homozygous) of the gene. The APC clot based assay is based on a partial thromboplastin (PTT) assay and is a useful screening tool but is not as specific and sensitive as the molecular test. Any test for Factor V antigen will not be useful in the patients with APC because they have sufficient quantity of Factor V. However, it is resistant to activated protein C. Antithrombin antigen assay is useful for patients who inherited antithrombin deficiencies, not for patients with APC.
In which of the following conditions would you NOT expect to find Howell-Jolly bodies? A) Sickle cell anemia B) Iron deficiency anemia C) Post splenectomy D) Megaloblastic anemia
B) Iron deficiency anemia Howell Jolly bodies are spherical dark purple granules in the erythrocyte (only one or two). They are composed of nuclear (DNA) fragments associated with nuclear maturation abnormalities. When the nucleus is extruded, the Howell-Jolly body is left behind (until removed by splenic macrophages). Iron deficiency anemia is a very common nutritional deficiency due to decreased iron availability or chronic blood loss. The blood picture in well-developed iron deficiency anemia shows microcytic hypochromic anemia. One of the spleen's functions is pitting, referred to as "pluck out" particles (such as Howell-Jolly bodies) from intact erythrocytes. Post splenectomy, hypofunction of the spleen (or autosplenectomy in sickle cell anemia) result in the presence of Howell-Jolly bodies. Megaloblastic anemia is the result of defective DNA synthesis. The presence of macro-ovalocytes and the presence of Howell-Jolly bodies are found on the peripheral blood smear.
When preparing a slide for morphologic examination, what is the reason for adding a drop of albumin to the cerebrospinal fluid (CSF) sample prior to cytocentrifugation? A) Enhance staining of the elements. B) Preserve the integrity of the cells. C) Increases the fluid volume so that cells will form a monolayer on the slide. D) Dilute the sample
B) Preserve the integrity of the cells The addition of a drop of 30% albumin helps to preserve the integrity and morphology of the cells in the hypotonic CSF. Albumin is not used to enhance the stain or dilute the sample. The cytocentrifugation process distributes the cellular elements in a monolayer.
Patients who undergo urologic procedures, as well as those with genitourinary tract diseases such as prostate cancer can sometimes be prone to diffuse hemorrhage. A possible cause of this could be which of the following? A) Dysfunction of platelets B) Release of urokinases C) Initiation of tissue factor released from endothelial cells D) Release of PGL (a prostacyclin ) from endothelial cells
B) Release of urokinases The correct answer is the release of urokinases. In urologic procedures and diseases, urokinases can be released, which have fibrinolytic activity and could thus lead to excess fibrinolysis. Dysfunction of platelets has not specifically been found to be associated with diseases of the genitourinary tract. Tissue factor initiates coagulation and thus would not lead to excess bleeding but rather prevent it. PGL can prevent platelet aggregation but is also not associated with diseases of the genitourinary tract.
Considering the red cell distribution width (RDW) in alpha thalassemia, how would you expect the red blood cell histogram to look? A) Shifted to the right B) Shifted to the left C) Bimodal D) Normal
B) Shifted to the left The red blood cell distribution width (RDW) increases as the severity of alpha thalassemia increases because of changing MCV as the bone marrow produces smaller cells. In addition, if Hemoglobin H bodies are present, they result in the formation of schistocytes (RBC fragments) that can have an effect on the MCV and RDW. The red blood cell histogram will be more to the left if the cells are smaller and to the right if the cells are larger. A bimodal distribution shows two distinct peaks in the red blood cell histogram representing two different size red blood cell populations. This distribution can be seen with cold agglutinin disease and in patients with abnormally sized red blood cells following transfusion of normal red blood cells.
What is the characteristic RBC that is uniquely associated with HbSS? A) Target cell (codocyte) B) Sickle cell (drepanocyte) C) Polychromatophilic cell D) Spherocyte
B) Sickle Cell (drepanocyte) The drepanocyte or sickle cell shape the red blood cell assumes when the hemoglobin is deoxygenated and polymerizes. This is the result of the inherited mutation in HbS whereby a polar amino acid in the beta globin chain is substituted by a non-polar amino acid. This occurs mainly in patients who are homozygous for this mutation (HbSS). Although target cells can be seen in HbSS patients' blood, they are not specific to this condition. Target cells can be seen in other hemoglobinopathies and other anemias as well. Polychromatophylic RBCs can be seen in their smears as well, but they can be seen in almost all smears of patients who are compensating for anemia. Spherocytes are rounded-up cells and are characteristic of Hereditary Spherocytosis and other anemias but are not associated with Hb S.
What are the usual results of the mean corpuscular volume (MCV) and the red cell distribution width (RDW) in alpha thalassemia? A) Both within normal range B) The MCV is decreased but the RDW is usually increased C) The MCV is increased but the RDW is normal D) Both the MCV and RDW are decreased.
B) The MCV is decreased but the RDW is usually increased The thalassemias are classified as microcytic anemias, thus these patients have decreased MCV values. The red blood cell distribution width (RDW) increases as the severity of alpha thalassemia increases because of changing MCV as the bone marrow produces smaller cells. In addition, if Hemoglobin H bodies are present, they result in the formation of schistocytes (RBC fragments) that can have an effect on the MCV and RDW. Even if the patient is not anemic, someone with thalassemia typically has at least an MCV below range. The MCV is never increased in thalassemia since there is an insufficient amount of globin produced and the cells are smaller than normal. It is rare to have a decreased RDW in any condition, and particularly not thalassemia.
A test used to evaluate the abnormalities in the intrinsic coagulation pathway and to monitor heparin therapy is called: A) Platelet function assay (PFA) B) Prothrombin time (PT) C) Activated partial thrombloplastin time (aPTT or PTT) D) Erythrocyte sedimentation rate (ESR)
C) Activated partial thrombloplastin time (aPTT or PTT) aPTT is test used to evaluate abnormalities in the intrinsic coagulation pathway and to monitor heparin therapy. PFA test used to evaluate bleeding problems and monitor antiplatelet medication. PT is a test used to evaluate abnormalities in the extrinsic coagulation pathway and to monitor coumarin therapy. ESR is a common hematology test that measures the rate a which the red blood cells fall and settle in a period of one hour.
Each of the following has been shown to induce platelet aggregation EXCEPT? A) Epinephrine B) ADP C) Aspirin D) Collagen
C) Aspirin For platelet aggregation studies, commonly used aggregating reagents include collagen, ADP, epinephrine, ristocetin, or arachidonic acid. These are helpful in identifying conditions such as von Willebrand disease, Bernard-Soulier syndrome, Glanzmann's thrombasthenia, and storage pool disease. Aspirin has been shown to directly inhibit platelet function.
Which of the following can cause an automated platelet count to appear to be lower than it actually is? A) Platelet satellitism B) Platelet clumping C) Both platelet satellitism and platelet clumping D) Neither platelet satellitism and platelet clumping
C) Both platelet satellitism and platelet clumping Both platelet satellitism and platelet clumping can cause the appearance of a falsely low platelet count from an automated hematology analyzer. This is termed pseudothrombocytopenia. When a patient has a low platelet count with no prior history of thrombocytopenia, it is essential that a peripheral blood smear is made and evaluated to ensure that platelet clumping and/or platelet satellitism have not caused the low platelet count from the analyzer.
Which of the following is the cause of cytopenia in Myelodysplastic syndromes (MDS)? A) Unchecked clonal hematopoiesis B) Inability to incorporate iron into developing erythrocytes C) Excess apoptosis D) Myelofibrosis
C) Excess apoptosis Excess apoptosis of abnormal (dysplastic) cells results in fewer cells being released into the circulation, which leads to cytopenia. Although the MDS are clonal hematopoietic neoplasms, unchecked proliferation would lead to high counts, as seen in the Myeloproliferative diseases. The difference is that in MDS, abnormal dysplastic cells are produced, which are destroyed in the bone marrow. Although some of the MDS, such as Refractory Anemia with Ringed Sideroblasts (RARS), show iron-containing sideroblasts, the ringed sideroblasts in RARS are due to abnormal cell development, and not specifically due to the inability to incorporate iron into hemoglobin, as occurs in the non-neoplastic disease Sideroblastic Anemia. Myelofibrosis can lead to pancytopenia. However, this is not a major mechanism in the MDS.
Which white blood cell population would have the MOST side scatter when analyzed using flow cytometry? A) Monocytes B) Lymphocytes C) Granulocytes D) Erythrocytes
C) Granulocytes The correct answer is granulocytes. Side scatter is a measurement of cell complexity (granularity). As the name suggests, granulocytes are the most granular blood cell, thus they have the most side scatter of the cell populations listed. Monocytes do not have granules, so they would not generate a lot of side scatter. Lymphocytes do not typically have granules (although they can rarely contain a few azurophilic granules) and would have much less side scatter than granulocytes. Erythrocytes are not a type of white blood cell and do not exhibit side scatter.
The gel electrophoresis pattern for hemoglobin S (HbS) shows which of the following migration patterns? A) HbS migrates alone in alkaline and with HbD in acid electrophoresis. B) HbS migrates with HbD in alkaline and with HbA in acid electrophoresis. C) HbS migrates with HbD in alkaline and alone in acid electrophoresis. D) HbS migrates with HbA in alkaline and HbD in acid electrophoresis.
C) HbS migrates with HbD in alkaline and alone in acid electrophoresis. HbS migrates with HbD (and HbG) in alkaline and alone in acid electrophoresis. On cellulose acetate (pH 8.6 = alkaline), HbS appears between HbF and HbA2. On citrate agar (pH 6.2= acidic), HbS appears between HbC and HbA .
A technologist decides to make a 1:20 dilution of cerebrospinal fluid (CSF) after briefly evaluating a portion of the sample microscopically. After making the dilution and charging the chambers, the number of observed cells in each of the large squares of the hemocytometer is >100. What should the technologist do to obtain the most accurate count? A) Count all four corner squares. B) Make a smaller dilution C) Make a larger dilution. D) No dilution is necessary.
C) Make a larger dilution The best choice would be to make a larger dilution before performing the cell count. This will provide the most accurate results.
Hematocrit is: A) Percentage of blood made up of serum B) Concentration of serum X 100 C) Percentage of blood made up of red blood cells D) Concentration of red cells X 100
C) Percentage of blood made up of red blood cells Hematocrit, also known as red cell packed cell volume, is the proportion of red blood cells in whole blood that is typically reported as a percentage. Hematocrit measurement may be done by centrifugation or through calculations performed on an automated hematology instrument. Along with the hemoglobin level, the hematocrit measurement is used to determine if a patient has anemia. Hematocrit reference ranges vary by age and sex. Additionally, hematocrit may be affected by the patient's state of hydration and patient positioning during collection.
Which parasite demonstrates the following findings on a blood smear from a patient with suspected malaria? Enlarged RBCs, some with fine brownish granules > 12 parasites in some cells Amoeboid structures Schüffner's dots A) Plasmodium falciparum B) Plasmodium ovale C) Plasmodium vivax D) Plasmodium malariae
C) Plasmodium vivax Plasmodium vivax characteristically displays Schuüffner's dots and often enlarged RBCs along with brownish granules. Plasmodium vivax can also have 12-24 merozoites present in each cell, actually filling the entire RBC. This parasite also has very irregular shapes, often referred to as "Amoeboid." Plasmodium falciparum does not display Shüffner's dots. Plasmodium ovale does display Shüffner's dots in all stages but is not as amoeboid as Plasmodium vivax. Plasmodium ovale characteristically has about 6-12 merozoites. Also, Plasmodium ovale characteristically shows enlarged, ovoid RBCs with fimbriated edges. Plasmodium malariae do not display Shüffner's dots and contains 6 to 12 merozoites.
Which of the following laboratory results would be seen in a patient with acute Disseminated Intravascular Coagulation (DIC)? A) Prolonged PT, decreased fibrinogen, elevated platelet count, increased FDP B) Normal PT, decreased fibrinogen, decreased platelet count, decreased FDP C) Prolonged PT, decreased fibrinogen, decreased platelet count, increased FDP D) Normal PT, increased fibrinogen, decreased platelet count, decreased FDP
C) Prolonged PT, decreased fibrinogen, decreased platelet count, increased FDP In DIC or disseminated intravascular coagulation, the prothrombin time is increased due to the consumption of the coagulation factors due to the tiny clots forming throughout the vasculature. This is also the reason that the fibrinogen levels and platelet levels are decreased. Finally, FDP, or fibrin degradation products, are increased due to the formation and subsequent dissolving of many tiny clots in the vasculature. The FDPs are the pieces of fibrin that are left after the fibrinolytic processes take place.
A smear that is prepared from equal parts of new methylene blue and whole blood is used for which of the following? A) WBC differential B) Platelet estimate C) Reticulocyte count D) Manual RBC count
C) Reticulocyte count New methylene blue is a supravital stain used to visualize remnant cytoplasmic RNA and organelles (e.g., mitochondria, ribosomes) in reticulocytes. A WBC differential and platelet estimate should be performed from a Romanowsky-stained (e.g., Wright-Giemsa) peripheral blood smear. Manual red blood cell counts are occasionally performed using a hemacytometer. Specimens are typically left unstained before analysis.
Which of the following is an important technique consideration in order to obtain consistently high quality bone marrow smears? A) Use the largest drop of marrow possible for each slide. B) Do not prepare the slides at the patient bedside. C) Select or concentrate bone marrow spicules, ensuring they are transferred to the slide. D) Only make one slide.
C) Select or concentrate bone marrow spicules, ensuring they are transferred to the slide. To obtain consistently high-quality smears, it is necessary to select or concentrate the bone marrow spicules (fragments). Selecting or concentrating fragments can be performed with different methodologies. At the patient bedside, some clinicians will use the touch-preparation or pull-preparation method while tilting the slide to allow excess blood to roll off. This leaves more of the bone marrow spicules on the slide. This can be wasteful and rather messy but does not require a high level of skill.A less wasteful method is to pour a portion of the marrow aspirate into a small petri dish and swirl it about, then tilt the dish to reveal the marrow spicules. These can then be extracted using a capillary pipette with a micro-pipette bulb and transferred to the slide for use in making smears. This technique allows the laboratory professional to make numerous smears containing fragments rather than relying on the random luck of the drop. You would not want to use a very large drop of marrow as this would probably not smear out to a readable layer of cells. Slides can be prepared at the patient's bedside if the work area is prepared sufficiently to ensure slides can be easily made. Making slides at the patient bedside is also dependent on hospital policy. It is important to prepare as many slides as possible from the obtained sample to provide the opportunity for choosing the best quality slides and for special stains if needed.
Neoplastic T lymphocytes with irregular, convoluted (cerebriform) nuclear outlines best describe which of the following? A) Gaucher cells B) Mott cells C) Sezary Cells D) Leptocytes
C) Sezary Cells Sezary cells are neoplastic T lymphocytes that have irregular, convoluted (cerebriform) nuclear outlines. Gaucher cells are large macrophages with small, eccentric nuclei. The cytoplasm of Gaucher cells usually appears wrinkled or striated. Mott cells are plasma cells that are filled with Russell bodies (globules of immunoglobulin). Leptocytes are red blood cells that are thin and flat, with the hemoglobin dispersed at the periphery of the cells. They appear cup-shaped.
Complaints of pain from a patient with sickle cell disease are most likely associated with which of the following conditions/events? A) Hemolytic anemia B) Infection C) Vaso-occlusive crisis D) Aplastic crisis
C) Vaso-occlusive crisis Pain is a warning sign that is related to vaso-occlusion and life-threatening complications. Chronic hemolytic anemia is associated with sickle cell disease, but is the not the cause of severe pain. Infection can trigger vaso-occlusion, but is not the direct cause of the pain that occurs during a vaso-occlusive crisis. An aplastic crisis is not the cause of a vaso-occlusive crisis.
Which of the following best represents the quantity of resultant bleeding in order of smallest bleed to largest (assuming identical trauma)? A) Artery, Arteriole, Vein B) Venule, Artery, Vein C) Venule, Vein, Artery D) Artery, Vein, Arteriole
C) Venule, Vein, Artery The quantity of a bleed in order of smallest bleed to largest would be: venule, vein, arteriole, then artery. This corresponds to a decrease in pressure, and to the size of the vessels. Artery, being closest to the heart has the highest pressure. Arterioles are smaller arteries that feed the capillaries. Venules direct the blood from capillary to a larger vein where the pressure is smaller than in arteries.
Which disorder exhibits a genetic code that is incompatible with life? A) Heterozygous alpha thalassemia minor B) Homozygous alpha thalassemia minor C) Hemoglobin H disease D) Alpha thalassemia major
D) Alpha thalassemia major Alpha thalassemia major, also known as Hydrops Fetalis, is exhibited when all four alpha chain gene loci are deleted or non-functional. The alpha chain is crucial to the formation of hemoglobin variants that can conduct normal oxygen transport and gas exchange. The genetic code --/-- (alpha thalassemia major) is therefore incompatible with life. Heterozygous alpha thalassemia minor has one inactive alpha gene and is known as a silent carrier. The remaining three alpha genes can synthesize enough alpha chains for normal hemoglobin synthesis. Homozygous alpha thalassemia minor, also known as alpha thalassemia trait, has two inactive active genes. This abnormality produces a mild anemia. Hemoglobin H disease has three inactive alpha genes. Hemoglobin H is associated with myeloproliferative or myelodysplastic disorders and mental retardation.
Which of the following cells have pale blue cytoplasm with a few azurophilic granules and an oval or indented nucleus? A) Monocyte B) Segmented neutrophil C) Eosinophil D) Lymphocyte
D) Lymphocyte Lymphocyte: Pale blue cytoplasm with a few azurophilic granules. The nucleus may be oval or indented. Monocyte: Blue-gray opaque cytoplasm. The nucleus may have convolutions. Segmented neutrophil: Light pink cytoplasm with fine granules. Nucleus with 2-5 lobes. Eosinophil: Colorless cytoplasm with large red-orange refractile granules. The nucleus is usually bi-lobed.
A patient has the following hematology test results. Classify the anemia present by choosing one of the options below. Hgb = 8.1 g/dL Hct = 31% RBC = 4.0 x 10^12/L A) Macrocytic, hypochromic B) Normocytic, normochromic C) Microcytic, normochromic D) Microcytic, hypochromic
D) Microcytic, hypochromic To classify the type of anemia present, it is necessary to solve for the RBC indices. MCV = (Hct/RBC) x 10 fL (average size, low value indicates microcytosis) MCH = (Hb/RBC) x 10 pg (average Hb per cell) MCHC = (Hb/Hct) x 100% (average Hb concentration per cell, low value means hypochromia) The MCV, in this case, would be 78 fL (decreased), the MCH is 20 pg (decreased), and the MCHC is 26% (decreased). Therefore, this anemia is classified as microcytic, hypochromic anemia.
Degenerated erythrocyte cytoplasmic organelles that contain iron are called: A) Cabot rings B) Howell-Jolly bodies C) Heinz bodies D) Pappenheimer bodies
D) Pappenheimer bodies Pappenheimer bodies are aggregates of mitochondria, ribosomes, and iron particles. They are associated with iron-loading anemias and some hemolytic anemias. Cabot rings are nuclear remnants or a result of abnormal histone synthesis. They can be seen in lead poisoning and pernicious anemia. Howell-Jolly bodies are nuclear remnants composed of DNA, seen in accelerated erythropoiesis, post-splenectomy, and other conditions. Heinz bodies are precipitated, denatured hemoglobin present in G6PD deficiency and some hemolytic anemias.
As an RBC ages, all of the following are true EXCEPT: A) The membrane becomes less flexible. B) The cellular hemoglobin concentration increases. C) Glycolysis and other enzyme activity decrease. D) They become less prone to phagocytosis.
D) They become less prone to phagocytosis. The correct answer is 'They become less prone to phagocytosis'. The opposite is true. As the RBC ages, it becomes more susceptible to being phagocytized, most often in the spleen.As RBCs age, the following points are true: The membrane becomes less flexible. The concentration of cellular hemoglobin increases. Enzyme active diminishes, particularly glycolysis
All of the following would be considered a part of the body's cellular immune system EXCEPT? A) Macrophages B) Mast cells C) Neutrophils D) Thrombocytes
D) Thrombocytes Thrombocytes, or platelets, are involved with hemostasis, not immunity. Body defense systems include cellular and molecular components. The cellular component includes phagocytic cells, inflammatory mediators, and natural killer cells. The phagocytic cells include neutrophils, monocytes, and macrophages. Cells that release inflammatory mediators include basophils, mast cells, and eosinophils. The molecular component includes complement, acute phase proteins, and cytokines.
The gene loci for the alpha-globin chains are adjacent to the locus for which other globin chain? A) Beta B) Delta C) Epsilon D) Zeta
D) Zeta The order of globin gene loci on chromosome 16 is Zeta, Alpha 2, and Alpha 1. Beta globin gene, delta globin gene, and epsilon globin genes are found on chromosome 11.
