SUCCESS! In Clinical Laboratory Science: Hematology - Leukocyte Disorders Pt 1
A. "Wrinkled" cytoplasm due to an accumulation of glucocerebroside A. Gaucher disease is a lipid storage disorder in which there is an accumulation of glucocerebroside in the macrophages because of a genetic lack of glucocerebrosidase, an enzyme required for normal lipid metabolism. Gaucher cells are found in the liver, spleen, and bone marrow. Niemann-Pick disease is caused by a deficiency of sphingomyelinase in which "foamy" macrophages, called Niemann-Pick cells, are filled with sphingomyelin. Normal acrophages may contain iron and other cellular debris.
A Gaucher cell is best described as a macrophage with A. "Wrinkled" cytoplasm due to an accumulation of glucocerebroside B. "Foamy" cytoplasm filled with unmetabolized sphingomyelin C. Pronounced vacuolization and deposits of cholesterol D. Abundant cytoplasm containing storage iron and cellular remnants
C. Essential thrombocythemia C. Primary or essential thrombocythemia (ET) is a chronic myeloproliferative disorder in which the main cell type affected is the platelet. An extremely high number of platelets are produced, but abnormal platelet function leads to both bleeding and clotting problems. The bone marrow shows megakaryocytic hyperplasia. The hemoglobin value and platelet count are increased in polycythemia vera, and CML is characterized by a high WBC count. Malignant thrombocythemia must be differentiated from a reactive thrombocytosis seen in patients with infection or following surgery. In reactive causes, the platelet count is rarely over 1 million X 109/L, platelet function is normal, and thrombocytosis is transient.
A patient with normal hemoglobin and WBC count values, a persistently elevated platelet count (over 1000 X 109/L), increased marrow megakaryocytes, and a history of frequent bleeding and clotting episodes most likely has A. Polycythemia vera B. Chronic myelofibrosis C. Essential thrombocythemia D. Chronic myelogenous leukemia
B. Idiopathic myelofibrosis B. The bone marrow is progressively replaced by fibrotic tissue in myelofibrosis, a chronic myeloproliferative disorder. Attempts to aspirate bone marrow usually result in a "dry tap." A biopsy stain demonstrates increased fibrosis (fibroblasts are thought to be stimulated by megakaryocytes). The presence of teardropshaped red blood cells is an important feature of myelofibrosis. In addition, abnormal platelets, a leukoerythroblastic blood profile and myeloid metaplasia in the spleen and liver are often associated with this disease. A high LAP score (reference range 13-160) and increased RBC mass are found in polycythemia vera, but the LAP score is low in chronic myelogenous leukemia.
An adult patient with massive splenomegaly has mild anemia, a slightly elevated WBC count, and an LAP score of 170. The blood smear shows teardrop erythrocytes and leukoerythroblastosis. These findings are most consistent with A. Chronic myelogenous leukemia B. Idiopathic myelofibrosis C. Primary polycythemia D. Primary thrombocythemia
A. Burkitt lymphoma A. The lymphoid cells of B cell acute lymphoblastic leukemia (FAB type L3) are morphologically identical to the malignant B cells of Burkitt lymphoma (large cells with basophilic cytoplasm and cytoplasmic lipid vacuoles). Although the site of origin is the bone marrow in B cell ALL and the tissues in Burkitt lymphoma, the World Health Organization (WHO) classifies them as the same disease entity with different clinical presentations (Burkitt leukemia/lymphoma). Both chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are malignant proliferations of small, mature lymphocytes, and diagnosis is based on the predominant site of involvement. Mycosis fungoides and Sezary syndrome are different stages of a cutaneous T cell lymphoma in which the skin is the early site of involvement, with subsequent progression to the bone marrow and blood.
Based on the WHO classification system, B cell ALL (FAB type L3) and represent different clinical presentations of the same disease entity. A. Burkitt lymphoma B. Hodgkin lymphoma C. Mycosis fungoides D. Small lymphocytic lymphoma
B. Increased albumin level B. The overall reaction of the body to tissue injury or invasion by an infectious agent is known as inflammation. This response brings leukocytes to the site of infection or tissue damage and is associated with activation of inflammatory mediators, including cytokines (IL-1), molecules released by cells (histamine), and byproducts of plasma enzyme systems (complement, kinins, fibrin). The plasma concentration of positive acute-phase reactants (APRs), such
In a patient with fever of unknown origin, which of the following findings is not consistent with an inflammatory process? A. Increased C-reactive protein B. Increased albumin level C. Increased fibrinogen level D. Increased erythrocyte sedimentation rate
C. B lymphocytes C. The Epstein-BaiT vims (EBV) attaches to receptors on B lymphocytes, and the virus is incorporated into the cell. The infection generates an intense immune response of T cells directed against infected B cells. It is the activated T lymphocytes that comprise the majority of reactive lymphocytes seen in the blood of patients with infectious mononucleosis. Other B cells produce nonspecific polyclonal (heterophile) antibody in response to the EBV infection.
In patients with infectious mononucleosis, which blood cells are infected by the causative agent? A. Monocytes B. T lymphocytes C. B lymphocytes D. Histiocytes
A. Pelger-Huet A. "True" Pelger-Huet anomaly is a benign autosomal dominant trait characterized by hyposegmentation of the granulocytes, coarse nuclear chromatin, and normal cytoplasmic granulation. The cells have no functional defect. It is of practical importance to recognize this anomaly so that it is not confused with a shift to the left due to infection. Acquired or "pseudo" Pelger-Huet is commonly associated with myeloproliferative disorders, myelodysplastic syndromes, or drug therapy. Pelgeroid cells are hyposegmented and the cytoplasm is frequently hypogranular.
In which anomaly is a failure of granulocytes to divide beyond the band or twolobed stage observed? A. Pelger-Huet B. May-Hegglin C. Alder-Reilly D. Chediak-Higashi
A. Cushing syndrome A. Eosinophils are decreased in Gushing syndrome, in which the adrenal glands secrete large amounts of adrenocorticosteroids. Eosinophils are increased in allergic disorders, various skin diseases, and certain types of parasitic infections (especially those due to intestinal and tissuedwelling worms). Eosinophilia is also seen in chronic myelogenous leukemia and Hodgkin lymphoma.
In which of the following are eosinophils not increased? A. Cushing syndrome B. Allergic disorders C. Skin disorders D. Parasitic infection
D. Chronic lymphocytic leukemia (CLL) D. Progression to acute leukemia is a very unlikely event for patients with chronic lymphocytic leukemia, even though there is no cure. Patients with chronic myelogenous leukemia typically progress to "blast crisis," most often of myeloid type, unless treated with imatinib mesylate (Gleevec®) in the chronic phase. Refractory anemia with excess blasts (RAEB) is the most likely type of myelodysplastic syndrome to develop acute myelogenous leukemia. Refractory anemia with ringed sideroblasts (RARS) is "preleukemic" but fairly stable.
In which of the following is progression to acute leukemia least likely? A. Chronic myelogenous leukemia (CML) B. Refractory anemia with excess blasts (RAEB) C. Refractory anemia with ringed sideroblasts (RARS) D. Chronic lymphocytic leukemia (CLL)
C. IgG light chains C. The secretion of large amounts of monoclonal IgG or other immunoglobulin light chains by a malignant clone of plasma cells produces a characteristic M spike on serum and urine protein electrophoresis. In some cases, only the light chains are produced in excess. Because the light chains are easily cleared by the kidneys, they may appear only in the urine (Bence-Jones proteinuria). Renal impairment in multiple myeloma is associated with the toxic effects of filtered light chains. High levels of serum beta microglobulin correlate with the myeloma tumor burden. Cryoglobulins are proteins that precipitate in the cold and may be seen in multiple myeloma and Waldenstrom macroglobulinemia.
Multiple myeloma is characterized by the presence in urine of large amounts of A. Cryoglobulins B. IgG heavy chains C. IgG light chains D. Beta microglobulins
B. A folate antagonist (e.g., methotrexate) B. A drug-induced megaloblastic blood profile with macrocytic ovalocytes and hypersegmented neutrophils is shown in Color Plate 11. This is a common finding in patients receiving antifolate chemotherapeutic drugs such as methotrexate. Recombinant erythropoietin is associated with a reticulocyte response and used to treat a variety of conditions, such as renal disease, anemia of chronic disease, or anemia caused by chemotherapy. Chloramphenicol is an antibiotic with a known association for aplasia due to marrow suppression.
The blood shown in Color Plate 11 is from a leukemia patient following treatment. These findings are most suggestive of therapy with A. Corticosteroids (e.g., prednisone) B. A folate antagonist (e.g., methotrexate) C. Recombinant erythropoietin D. Chloramphenicol
B. CD10,CD19 B. The blast cells shown in Color Plate 15 are from a child with CALLA positive, precursor B acute lymphoblastic leukemia. The malignant cells would be expected to express CD 10, the common ALL antigen marker; the B cell lineage marker CD 19; and TdT (terminal deoxynucleotidyl transferase), a marker on early lymphoid cells. Precursor T acute lymphoblastic leukemia would express TdT and the T cell markers CD2 and CD7. CD 13 and CD33 are myeloid markers, and CD14 is a marker for monocytic cells.
The child whose blast cells are shown in Color Plate 15 has acute lymphoblastic leukemia that is precursor B cell type and CALLA positive. Analysis by flow cytometry would likely show cells that immunophenotype for A. CD2,CD7 B. CD10,CD19 C. CD13,CD33 D. CD14,CD34
A. B cell A. B cell chronic lymphocytic leukemia (CLL) is by far the most common type found in the United States. Immune dysfunction because of hypogammaglobulinemia occurs in later stages of the disease, as does thrombocytopenia. Development of warm autoimmune hemolytic anemia is a frequent occurrence in patients with CLL. Treatment for B cell CLL is conservative and aimed at controlling symptoms. T cell CLL is a rare and is a more aggressive disease.
The most common type of chronic lymphocytic leukemia (CLL) in the United States involves the A. B cell B. NK cell C. T cell D. Plasma cell
A. Acute leukemia A. The "packed" bone marrow with predominantly immature blast cells and few normal precursor cells, as seen in Color Plate 16, is most indicative of a patient with acute leukemia. Although chronic leukemias usually have a hypercellular marrow, the malignant cells are more mature or differentiated (i.e., able to mature beyond the blast stage). Myelodysplastic syndromes are associated with a hypercellular bone marrow, but the marrow blast percent is less than 20% (using WHO criteria). Aplastic anemia is characterized by a hypocellular bone marrow with few cells.
The patient whose bone marrow is shown in Color Plate 16 most likely has a(n) A. Acute leukemia B. Chronic leukemia C. Myelodysplastic syndrome D. Aplastic anemia
B. Chronic lymphocytic leukemia B. The blood shown in Color Plate 14 is from an elderly patient with chronic lymphocytic leukemia (CLL), which is characterized by an absolute lymphocytosis and a predominance of small, mature lymphocytes with hyperclumped nuclear chromatin. Elevated leukocyte counts are usual, as are fragile, smudged lymphocytes. Acute lymphoblastic leukemia (ALL) typically occurs in children and is characterized by immature lymphoid cells. Plasmacytoid lymphocytes and red cell rouleaux may be found in the blood of individuals with Waldenstrom disease. Viral infections are associated with a lymphocytosis and the presence of reactive lymphocytes that are heterogeneous in morphology. Reactive lymphocytes exhibit a variety of forms with regard to size and cytoplasmic staining intensity as compared to the homogeneous cell populations present in malignant disorders such as CLL and ALL.
The peripheral blood shown in Color Plate 14 is from a 69-year-old female. Her WBC count was 83.0 X 109 cells/L (83.0 X 103/(xL) and her platelet count was normal. Based on the cell morphology and this information, what is the most likely diagnosis? A. Acute lymphoblastic leukemia B. Chronic lymphocytic leukemia C. Waldenstrom macroglobulinemia D. Viral infection
D. Leukoerythroblastic reaction D. A leukoerythroblastic blood profile, which refers to the presence of both immature neutrophils and nucleated red cells, is most commonly associated with conditions involving bone maiTOw infiltration by malignant cells (leukemia, cancer) or replacement by fibrotic tissue. A neutrophilic left shift is defined as the presence of increased numbers of immature neutrophils in the blood without nucleated red cells. A regenerative left shift and a neutrophilic leukemoid reaction are characterized by varying degrees of leukocytosis and a neutrophilic left shift, most often found in response to infection. In contrast, a degenerative left shift refers to leukopenia and a left shift that may occur if marrow pools are depleted in an overwhelming infection (use exceeds the bone marrow's capacity to replace).
The presence of both immature neutrophils and nucleated erythrocytes in the peripheral blood is most accurately called a A. Neutrophilic left shift B. Regenerative left shift C. Neutrophilic leukemoid reaction D. Leukoerythroblastic reaction
C. Acute promyelocytic leukemia (FAB type M3) C. The abnormal cells found in acute promyelocytic leukemia (FAB type M3) contain large numbers of azurophilic granules. These granules contain procoagulants that on release hyperactivate coagulation, resulting in disseminated intravascular coagulation. Although other acute leukemias may trigger DIG, M3 is the one most frequently associated with this life-threatening bleeding complication. If DIG is resolved, many patients with acute promyelocytic leukemia respond favorably to therapy with retinoic acid, which causes maturation of the malignant promyelocytes. The presence of t(15;17) has diagnostic and prognostic significance, and acute promyelocytic leukemia is classified with "acute myeloid leukemias with recurrent cytogenetic translocations" by the World Health Organization (WHO). Acute myeloblastic leukemia with t(8;21) is also included in this WHO category (con-elates with FAB type M2).
The presence of the chromosomal abnormality t(15;17) and a high incidence of disseminated intravascular coagulation (DIC) is diagnostic of A. Acute myeloblastic leukemia without maturation (FAB type Ml) B. Acute myeloblastic leukemia with maturation (FAB type M2) C. Acute promyelocytic leukemia (FAB type M3) D. Acute myelomonocytic leukemia (FAB type M4)
D. Increased IgM and blood hyperviscosity D. Waldenstrom macroglobulinemia is caused by a proliferation of transitional B lymphocytes (lymphoplasmacytic or plasmacytoid lymphs) that secrete high amounts of monoclonal IgM. Because IgM is a macroglobulin, blood hyperviscosity is the cause of many of the symptoms found in this disease (bleeding and visual impairment). Plasmapheresis can reduce the IgM protein concentration. Hepatosplenomegaly is common in Waldenstrom disease (rather than bone lesions).
Which of the following are characteristic findings in Waldenstrom disease? A. Increased IgA and hepatosplenomegaly B. Increased IgE and renal failure C. Increased IgG and hypercalcemia D. Increased IgM and blood hyperviscosity
B. Bordetella pertussis (whooping cough) B. A striking lymphocytosis may be seen in children with pertussis, but normal lymphocytes, rather than reactive lymphocytes, are present. A relative and/or absolute lymphocytosis with reactive lymphocytes in various stages of activation, as seen in Color Plate 121, is characteristic of infection caused by Epstein-Barr virus (EBV), cytomegalovirus (CMV), and toxoplasmosis. A positive heterophile antibody test can help distinguish infectious mononucleosis caused by EBV from conditions with a similar blood picture. Epstein-Barr virus is also linked to Burkitt and Hodgkin lymphomas.
Which of the following infections does not reveal a blood picture as seen in Color Plate 12? A. Epstein-Barr virus (EBV) B. Bordetella pertussis (whooping cough) C. Cytomegalovirus (CMV) D. Toxoplasma gondii (toxoplasmosis)
C. Multiple myeloma C. Multiple myeloma is a malignant lymphoI proliferative disorder characterized by a clonal proliferation of plasma cells and multiple bone tumors. Myeloproliferative disorders are characterized by a proliferation of bone marrow cells (granulocytic, monocytic, erythrocytic, megakaryocytic), with usually one cell type primarily affected. For example, the main cell type affected in polycythemia vera is the erythrocyte, and the platelet is mainly affected in essential thrombocythemia. Transformation among the myeloproliferative disorders is frequent.
Which of the following is not classified as a myeloproliferative disorder? A. Polycythemia vera B. Essential thrombocythemia C. Multiple myeloma D. Chronic myelogenous leukemia
D. Lymphadenopathy D. Although a hallmark of acute lymphoblastic leukemias (ALL), lymphadenopathy is not associated with acute myelogenous leukemias. ALL is also more likely to have central nervous system involvement, and the CNS is a potential site of relapse. Hepatomegaly and splenomegaly are associated with both types of acute leukemia, as well as with the presence of anemia, neutropenia, and thrombocytopenia. Common presenting symptoms are fatigue, infection, or bleeding. If untreated, both acute myelogenous and lymphoblastic leukemias have a rapidly fatal course.
Which of the following is not commonly found in acute myelogenous leukemias? A. Neutropenia B. Thrombocytopenia C. Hepatosplenomegaly D. Lymphadenopathy
D. Oxidative respiratory burst D. Chronic granulomatous disease (CGD) is a hereditary disorder in which neutrophils are incapable of killing most ingested microbes. The disease is usually fatal because of defective generation of oxidative metabolism products, such as superoxide anions and hydrogen peroxide, which are essential for killing. Chemotaxis, lysosomes, phagocytosis, and neutrophil morphology are normal. Several variants of CGD have been described, with specific enzyme defects and different modes of inheritance. The more common type of CGD has a sex-linked inheritance pattern.
Which of the following represents the principal defect in chronic granulomatous disease (CGD)? A. Chemotactic migration B. Phagocytosis C. Lysosomal formation and function D. Oxidative respiratory burst
C. Hairy cells contain tartrate-resistant acid phosphatase. C. The malignant cells of hairy cell leukemia (HCL) stain positive with acid phosphatase in the presence of tartaric acid; that is, hairy cells contain tartrate-resistant acid phosphatase (TRAP). Normal cells stain acid phosphatase positive, but staining is inhibited by the addition of tartrate. HCL is a chronic disorder, mainly confined to the elderly. The spleen usually shows marked enlargement, but enlarged lymph nodes are very uncommon. Hairy cells are malignant B cells, and pancytopenia is usual at presentation.
Which of the following statements about hairy cell leukemia is true? A. It is an acute disease, primarily affecting young adults. B. Splenomegaly is an unusual finding. C. Hairy cells contain tartrate-resistant acid phosphatase. D. Hairy cells are abnormal T lymphocytes.
D. Presence of giant binucleated Reed Sternberg cells with prominent nucleoli D. The presence of Reed-Sternberg cells is the diagnostic feature of Hodgkin disease (lymphoma). The Reed Sternberg giant cell is usually binucleated, and each lobe has a prominent nucleolus. Studies suggest that this neoplastic cell is of B cell lineage. It is not found in the blood but only in the tissues. Circulating T cells with a convoluted nucleus describe the Sezary cells seen in Sezary syndrome, the leukemic phase of mycosis fungoides. A monoclonal population of large lymphoid cells or immature B cells with nuclear clefts is most descriptive of lymphoma cells, present in certain types of peripheralized non-Hodgkin lymphoma, that have spread from the tissues to the bone marrow and blood.
Which of the following suggests a diagnosis of Hodgkin disease rather than other lymphoproliferative disorders? A. Presence of a monoclonal population of large lymphoid cells B. Predominance of immature B cells with irregular nuclear clefts C. Circulating T cells with a convoluted, cerebriform nucleus D. Presence of giant binucleated Reed Sternberg cells with prominent nucleoli
C. Human immunodeficiency virus (HIV) C. The elevated WBC count and toxic neutrophils seen in Color Plate 13 indicate an extreme response to severe infection (bacterial septicemia, fungal) or treatment with recombinant myeloid growth factors. GM-CSF and GCSF are used to increase cells for peripheral stem cell transplant and reduce infection in patients after high-dose chemotherapy or during transplant. A leukemoid reaction is one that mimics the type of blood picture seen in leukemia. It is associated with extremely high leukocyte counts (often greater than 50 X 109 cells/L) and is usually found in severe infection. The most common type of leukemoid reaction is neutrophilic, but lymphocytic leukemoid reactions also occur. HIV infection is associated with leukopenia and lymphocytopenia.
Which of the following would not cause a total WBC count of 62.2 X 109/L (62.2 X 103/uL) and the blood findings seen in Color Plate 13? A. Treatment with myeloid growth factors B. Gram-negative septicemia C. Human immunodeficiency virus (HIV) D. Systemic fungal infection