Hematology Lab Simulator

Erythrocytes Platelets and erythrocytes do not have CD 45 on their cell surfaces.

The image on the right contains the fluorescence data from CD45 from a flow cytometry analysis. Note that virtually all cells in the gated population have CD45 surface antigens. These cells could therefore be any of the following EXCEPT:

Clotting, plug formation, release of serotonin, and repair of the injured tissues.

What are function(s) of the platelet?

Interruption of DNA Synthesis Defective stem cell production results in the development of aplastic anemia. Interruption of hemoglobin production results in thalassemia. Interruption in the development of precursor cells is an anemia that is caused by chronic renal disease.

What is the mechanism that causes megaloblastic anemia?

M:E = 2.5:1

When assessing a bone marrow aspirate smear of an adult, a normal M/E ratio (myeloid to erythroid cells) would be?

Cell size

When using a flow cytometer, forward scatter measures which of the following parameters?

Alpha thalassemia silent carrier

Which alpha thalassemia shows no anemia or evidence of disease, although a slight decrease in the MCV and MCHC may be seen?

Chromosome 11

Which chromosome demonstrates a partial or full gene loci deletion in various forms of beta thalassemia?

Hb F HbF is increased in delta-beta thalassemia. It is increased to 100% in delta-beta thalassemia major.

Which hemoglobin will be increased in delta-beta thalassemia?

Erythropoietin

Which hormone is produced by the kidney and influences erythrocyte production?

Hemoglobin, Hematocrit, Red Blood Cell Count

Which of the following analytes will be falsely *DECREASED* due to hemolysis?

Touch preparations

Which of the following bone marrow processing procedures is best suited for a patient who had a dry tap?

Spherocytes When spherocytes are exposed to hypotonic solutions, they hemolyze quicker than normal sized, biconcave cells would. Osmotic fragility is the most useful test for confirmation of hereditary spherocytosis.

Which of the following cells demonstrate an increase in osmotic fragility?

Total count X % of cells counted The absolute cell count is the product of the percentage of a single leukocyte type multiplied by the total WBC count.

Which of the following formulas would you use to calculate absolute cell counts?

HbC Harlem Abnormal hemoglobins, such as HbC Harlem that cause RBCs to sickle, may produce a positive solubility test.

Which of the following non-HbS hemoglobins can also sickle and show a positive solubility test?

Echinocytes, stomatocytes When echinocytes are artifactual, they are commonly referred to as crenated red blood cells. If echinocytes are seen on the stained peripheral blood smear but not the wet preparation, the echinocytes are artifactual.

Which of the following red blood cell morphologies are frequently artifactual?

Nucleus may be round, peanut-shaped or bilobed. A blood smear from a patient with Pelger-Huet anomaly will contain hyposegmented neutrophils

Which of the following statements is true regarding hyposegmented neutrophils?

On average, 25% to 35% of ingested iron is absorbed each day. ----- On average, only 5% to 10% of ingested iron is absorbed each day.

Which one of the following statements about iron deficiency anemia (IDA) is false:

Myelodysplastic Syndromes It is called refractory anemia because the usual treatments for anemia are not effective. The term excess blasts is because there are typically about 5% blasts, which is more than seen in most chronic disorders.

"Refractory Anemia with Excess Blasts" (RAEB) is classified under which category?

Erythroleukemia This type is associated with either the presence of both erythroid and myeloid precursors OR strictly erythroid precursors. In the case above, there are both erythroid and myeloid precursors present in the peripheral smear.

A 90-year-old patient is admitted to the hospital with the following laboratory data: WBC: 9,000/mm3 PLT: 190,000/mm3 Hgb: 6.1 g/dL Differential:11% Neutrophils40% Lymphocytes4% Monocytes45% Myeloblasts45 NRBC's / 100 WBCBone Marrow: 45% Myeloblasts & 55% Megaloblastoid Erythroblasts Serum Vitamin B12 and Folic Acid: Normal The MOST likely diagnosis is:

Von Willebrand factor

A defect in which of the following factors causes impaired platelet adhesion and aggregation?

(IMAGE) Nucleated red blood cells, spherocytes, polychromatophilic cells, Howell-Jolly bodies

A known case of hemolytic disease of the newborn (HDN) is presented in the image on the right. Many different cellular morphologies are present. Apart from the obvious anisocytosis (microcytes and macrocytes), which additional red blood cell morphologies are worth reporting?

3.6 x 103/µL WBC count = (dilution ratio x # of cells counted x 10) / (# mm2 area counted)

A manual WBC count was performed. A TOTAL of 72 cells were counted in 4 large mm squares of a Neubauer-ruled hemacytometer. A 1:20 dilution was used. What is the calculated WBC count?

Beta thalassemia minor The laboratory findings typically include a mild, microcytic, hypochromic anemia, increased target cells (codocytes), and increased levels of Hemoglobin A2.

A patient has an increased RBC count with a decreased Hb and normal Hct. The MCV is microcytic and the RDW is within normal limits. Many codocytes are present on the peripheral smear. Serum iron is 165 µg/dL (normal = 60 -150 µg/dL), and the TIBC is 230 µg/dL (normal = 250 - 400 µg/dL). Consider also the findings on alkaline hemoglobin electrophoresis, which show an increased level of hemoglobin A2 of 5% (normal values are less than 3.5%).

Factor IX deficiency

A patient with a history of frequent mild bleeding episodes has the following results: Normal PT Prolonged aPTT corrected by normal plasma during mixing studies Which of the following could be a possible cause of the initial aPTT prolongation?

Normal finding 45 to 75% of the WBCs normally seen in the peripheral blood of infants are lymphocytes.

If greater than 50% lymphocytes were found on the peripheral blood smear of a 5 month old child you would suspect which of the following conditions?

Proximal ends of long bones occurs in the marrow of the vertebrae, skull, and proximal ends of long bones, as well as in the bone marrow of the ribs, and pelvis in adults.

In an adult, hematopoiesis occurs in which of the following listed sites?

Polychromatic normoblast Hemoglobin synthesis is detectable in the basophilic normoblast, but the formation of large amounts of hemoglobin begins in the polychromatic (polychromatophilic) normoblast

In which developmental stage do red blood cells begin forming hemoglobin in amounts large enough to be visualized on a Wright-stained bone marrow aspirate smear?

Alpha thalassemia minor

In which disorder may a mild anemia be present even with an increased red blood cell (RBC) count and normal adult hemoglobin electrophoresis?

Myeloperoxidase Auer rods will display the most intense reaction with Myeloperoxidase as they are made of fused granules which all contain the myeloperoxidase enzyme. Auer rods can be found in AML.

In which stain will auer rods have the most intense reaction?

Phlebitis

Inflammation of a vein is known as:

RDW RDW is defined as the coefficient of variation of the MCV or variability in sizes of the erythrocytes. Elevation of the RDW will be indicative of anisocytosis.

A technologist is evaluating a blood smear. The technologist notices variability in cell size. Which parameter from the automated complete blood count would confirm the anisocytosis observed on the blood smear?

Bernard Soulier Syndrome Bernard Soulier Syndrome is an inherited platelet disorder that is missing the platelet receptor Ib/IX/V. This receptor is used for Von Willebrand Factor to aid in platelet adhesion. Without this receptor, the patient is prone to mucocutaneous bleeding and bruising. Lab testing to confirm diagnosis would include prolonged bleeding time, thrombocytopenia, giant platelets, and no response to ristocetin.

A young child is brought in for a clinic visit for bleeding and bruising tendencies. Coagulation screening tests revealed normal PT and APTT levels. The CBC was overall normal with the exception of a low platelet count and giant platelets. Platelet aggregation studies were then ordered with normal responses to all agents except ristocetin which had no response. Which of the following is the disease correlates with these findings?

>95% HbA, <3.5% HbA2, <1-2% HbF Greater than 95% HbA is 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%).

Adult (normal) Hemoglobin is made up of the following composition:

CD20 The CD20 marker is NOT present on mature T cells. CD20 is expressed by B cells.

All of the following CD markers are present on a normal mature T cell, EXCEPT?

Factor X Factor X is part of the common pathway, and is activated by both intrinsic and extrinsic pathways (according to the in vitro model of coagulation).

All of the following factors are involved in the initial contact phase of the intrinsic pathway, EXCEPT:

Blood culture

All of the following tests are included in a complete blood count (CBC), EXCEPT?

(IMAGE) Sickle cell disease Hemoglobin electrophoresis is necessary to confirm this diagnosis. However, the presence of numerous target cells and sickle cells suggests HbSS or sickle cell disease.

An 8-year-old girl's peripheral blood smear is shown in the image on the right. Based on the peripheral blood image, what is a likely diagnosis?

A column which has 11 heavy-staining bands.

An SDS-agarose gel electrophoresis for determining different multimer sizes of von Willebrand factor (vWF) is performed on a group of patients. Which of the following would indicate a patient who does not have von Willebrand Disease (vWD)?

coagulation proteins Blood plasma will contain coagulation proteins, but not in a clotted tube where serum is present.

Blood serum contains each of the following substances except:

Basophil

Cell that contains histamine and heparin responsible for immediate hypersensitivity reactions.

Integrity of the RBC membrane The integrity of the membrane is compromised when macrophages remove the precipitated tetramers out of the cell and cells appear "bitten" (schiztocytes).

Hemoglobin H bodies can directly alter which of the following?

African countries

Hemoglobin S (HbS) is MOST common in which of the following countries?

vitamin B12 and folate deficiencies.

Hypersegmentation is an early indicator in megaloblastic conditions, such as anemia resulting from

B cells

It has already been established that the gated cell population is lymphocytic in nature. CD19 and CD20 cell surface antigens both appear on what type of lymphocytes?

thrombocytopenia and giant platelets

May-Hegglin Anomaly consists of

Stem Cell, Rubriblast, Prorubricyte, Rubricyte, Metarubricyte, Reticulocyte, Erythrocyte

Out of the choices below, which set of cells is arranged from least mature to most mature?

One third

The central pallor in a red blood cell is about _________ the diameter of the cell.

Acute Myelocytic Leukemia

The following stain reactions were resulted on a suspected case of leukemia: Myeloperoxidase + Sudan Black B + Chloroacetate Esterase + Nonspecific Esterases - Which of the following is the correct interpretation?

Histamine

The granules that basophils contain are composed of:

Decreased solubility of deoxygenated Hb S in solution produces visible turbidity. The insolubility of hemoglobin S when combined with a reducing agent will result in visible turbidity which is considered a positive result. This test does not differentiate Hb S disease from Hb S trait.

The most common screening test for Hb S, the hemoglobin solubility test, is based on which of the following principles?

Thrombosis

obstruction of a blood vessel caused by a stationary blood clot.