MLT Hematology/Coagulation Quiz Review
Acute disseminated intravascular coagulation is characterized by A hyopfibinogenemia B thrombocytosis C negative D-dimer D shortened thrombin time
A hypofibinogenemia The laboratory profile for a patient with acute DIC is increased PT, APTT, and decreased platelets and fibrinogen.
Blood collected in EDTA undergoes which of the following changes if kept at room temperature for 6-24 hours? A increased hematocrit and MCV B increased ESR and MCV C increased MCHC and MCV D decreased reticulocyte count and hematocrit
A increases hematocrit and MCV Tubes that remain at room temperature for more than 5 hours have unacceptable blood artifacts. This will affect the HCT and MCV.
Which of the following is the formula for absolute cell count? A number of cells counted/total count B total count/ number of cells counted C 10 x total count D % of cells counted x total count
D % of cells counted x total count The absolute concentration of each type of cell in a WBC differential is important for determining an increase or decrease in WBC population.
Thromboscytosis would be indicated by a platelet count of: A 50 x 10^3 uL B 200 x 10^3 uL C 300 x 10^3 uL D 600 x 10^3 uL
D 600 x10^3 uL Thrombocytosis is an increased platelet count, thrombocytopenia is a decreased platelet count. Normal range for a platelet count is 105-450 x 10^3 uL.
A blood sample from a patient with a high titer cold aggutinin, analyzed at room temperature with an electronic particle counter, would cause an error in the: A Hgb and MCV B MCH and WBC C WBC and RBC D MCV and MCHC
D MCV and MCHC The MCV will be falsely elevated from the agglutination cells, the RBC will be falsely decreased, and the MCHC, which is Hgb x 100/Hct, will be falsely elevated. Both the MCV and RBC are directly measured parameters. Hct is a calculated parameter ( RBC x MCV = Hct).
Which of the following is most closely associated with iron deficiency anemia? A iron overload in tissue B target cells C basophilic stippling D chronic blood loss
D chronic blood loss
In infectious mononucleosis, lymphocytes tend to be A small with little cytoplasm B normal C decreased D enlarged and indented by surrounding structures
D enlarged and indented by surrounding structures The most characteristic hematologic finding on the peripheral blood smear of a patient with infectious mononucleosis is increased number of lymphocytes, in particular, the atypical lymphocytes. Atypical lymphocytes usually constitute 10-20% of the cells in the differential count. The cells are larger than normal lymphocytes with more lobulated or indented nucleus shapes containing dense red-purple chromatin and nucleoli. The cytoplasm may be foamy, vacuolated, or basophilic often irregular borders that tend to flow around adjacent erythrocytes.
A blue top is drawn for coagulation studies and the sample is short draw. Results may be A falsely shortened B correct C unable to be obtained D falsely prolonged
D falsely prolonged Falsely prolonged results will occur if there is too much anticoagulant for the plasma. This also occurs with an increased Hct. Conversely,if a tube is overdrawn, there may be too little anticoagulant, resulting in a clot.
The components of Wright's stain include: A crystal violet and safranin B brilliant green and neutral red C new methylene blue and carbol fuchsin D methylene blue and eosin
D methylene blue and eosin
Which of the following is associated with Alder-Reilly inclusion? A membrane defect of lysosomes B Doyle bodies and giant platelets C two-lobed neutrophils D mucopolysaccharidosis
D mucopolysaccharidosis
In which of the following disease states are teardrop cells and abnormal platelets most characteristically seen: A chronic myelocytic leukemia B multiple myeloma C thalassemia D myeloid metaplasia
D myeloid metaplasia (Myelofibrosis)
The following results were obtained on a patient's blood: Hgb 11.5 g/dL HCT 40% MCV 89 fL MCH 26 pg MCHC 29% Examinations of a Wright stained smear of the same sample would most likely show: A macrocytic, normochromic erythrocytes B microcytic, hypochromic erythrocytes C normocytic, hypochromic erythrocytes D normocytic, normochromic erythrocytes
D normocytic, normochromic erythrocytes The RBC indices, MCV, MCH, and MCHC are used to classify the terms used to determine normochromic, hypochromic, or hyperchromic RBCs. Normal MCV = 80-99 fL, normal MCHC = 32-36 g/dL.
An automated platelet count indicates platelet clumping, which is confirmed by examining the smear. The technician should: A repeat the count on the same sample B report the automated count C perform a manual count D recollect in sodium citrate
D recollect in sodium citrate Platelet clumping is reduced by collecting the sample in sodium citrate because of the difference in dilution of the sodium citrate tube and the EDTA tube (caused by the amount of anticoagulant in the tube), results must be multiplied by 1.1 to correct for the dilution.
On setting up the electronic particle counter in the morning, one of the controls is lightly below range for the MCV. Which of the following is indicated? A call for service B adjust the MCV up slightly C shut down the instrument D repeat the control
D repeat the control Only one control is out, and it is only slightly out of range. The first course would be to rerun the control.
A patient has a high cold agglutination titer. Automated cell counter results reveal an elevated MCV, MCH, and MCHC. Individual erythrocytes appear normal on a stained smear, but agglutinates are noted. The appropriate course of action would be to: A perform the RBC, HGB, HCT determination using manual methods. B perform the RBC determination by a manual method; use the automated results for the HGB and Hct C repeat the determinations using a micro sample of diluted blood D repeat the determinations using a prewarmed micro sample of diluted blood
D repeat the determinations using a prewarmed micro sample of diluted blood Auto agglutination of anticoagulated blood can occur at room temperature in patients with a cold autoagglutinin. The MVC will be falsely elevated and the RBC count falsely decreased, resulting in an elevated MCHC. The blood sample should be warmed to 37 degrees Celsius and rerun.
The ISI in the INR represents the reagent's A activator B specificity C phospholipids D sensitivity
D sensitivity The ISI represents the international sensitivity index. The most responsive reagents have an ISI of 1.
When evaluating a smear for a reticulocyte count, the technician observes that the red blood cells are routinely overlapping throughout the entire slide. The most likely explanation is: A grease on the slide prevented even spreading B improper proportions of blood and stain were used C the slide was dried too quickly D the drop used for the slide preparation was too large
D the drop used for the slide preparation was too large Too large of a drop of blood will produce a thick smear; slowly pushing the blood will affect the distribution of the cells.
A CSF was collected from a 5 year old with a fever, and 3 tubes were transported to the lab. Tube #1 had 50,000RBC/cL and 0 WCB/mL. What is the most likely explanation for the discrepancy? A tube #3 was QNS B bacterial meningitis C subarachnoid hemorrhage D traumatic tap
D traumatic tap A traumatic tap is collection of body fluid that has blood contamination. The first tube will have the most contamination, so that subsequent tubes will show fewer blood cells. Cell counts should routinely be performed on the last tube to minimize the amount of cellular contamination due to tap.
A CSF was hazy and the WBC was too high to perform undiluted. The tech took 50 mL of sample and added 500 mL of saline. The cell count on the diluted sample was 200 WBC per mL. This should be multiplied by: A. 10 B. 11 C. 1/10 D. 1/11
b. 11 To calculate the dilution, take the amount of sample and divide it by the total of the new solution. The dilution is 50 uL divided by 500+50uL. This is 1/11 dilution. To correct the final answer, multiply by the inverse of the dilution, or 11.
D-dimer are produced from A cross-linked and stabilized fibrin clot B decreased fibrinogen and platelets C plasminogen converting to plasmin D generation of thrombin from endothelial cells
A cross link and stabilized fibrin clot D-dimers are produced from cross linked and stabilized fibrin clots. This clot is dissolved by plasma and d-dimmers are released. Therefore, d-dimer suggest a breakdown of fibrin clots, and indicate that clots have been formed at the site of injury.
Which of the following platelet responses is most like associated with classic von Willebrand's disease? A decrease platelet aggregation to ristocetin B normal platelet aggregation to ristocetin C absent aggregation to epinephrine, ADP, and collagen D decreased amount of ADP in platelets
A decrease platelet aggregation to ristocetin
A patient comes in for a work up for a bleeding disorder. The patient's PT and aPTT results are as follows PT = 14.5 sec (normal = 10.9 - 12.5 sec) aPTT = 45.7 sec (normal = 28.9 x35.5 sec) Which of the following factors may be deficient? A factor I (fibrinogen) B factor VII C factor VIII D factor IX
A factor I (fibrinogen) When both the PT and aPTT are prolonged, a common pathway factor (I, II, V, or X) is investigated. Factor VII and Factor IX deficiencies would cause only a prolonged aPTT, a Factor VII deficiency would result in only a prolonged PT.
A patient is admitted to the hospital with a WBC count of 250 x 10^3 uL. One parameter that may be falsely elevated by this WBC count is the: A hemoglobin B MCV C platelet count D reticulocyte count
A hemoglobin Elevated WBC counts cause turbidity in the solution when whole blood is diluted with HiCN(hemoglobin-cyanide) reagent whether this occurs in the manual procedure or in an automated instrument. This turbidity will affect the absorbance reading, and the dilution must be centrifuged prior to reading.
The majority of the iron in a adult is found as a constituent of: A hemoglobin B hemosiderin C myoglobin D transferrin
A hemoglobin Two-thirds of the iron in the body is bound to hemoglobin.
Which of the following is most closely associated with idiopathic hemochromatosis? A iron overload in tissue B target cells C basophilic stippling D ringed sideroblast
A iron overload on tissue
The erythrocyte sedimentation rate (ESR) can be falsely elevated by: A tilting the tube B refrigerated blood C air bubbles in the column D specimen being too old
A tilting the tube Tilting the tube accelerates the fall of the RBCs.
Which of the following coagulation factors is considered to be labile? A II B V C VII D X
B V Factor V is called labile factor because it's activity diminishes quickly at room temperature. Factor II called prothrombin, VII is called stable factor, and X is called Stuart-Prower factor.
In an automated cell counter, the WBC printed result is "+++". The next step is to: A. repeat after warming the sample to 37ºC B. make an appropriate dilution of the sample C. recalibrate the machine from pooled samples D. request a new sample immediately
B. make an appropriate dilution of the sample "+++" is an indicator that WBC count exceeds the upper reportable limit. The specimen must be diluted and re analyzed to bring the count within the analytical range of the instrument. The result would be multiplied by the dilution factor before reporting.
The white cell feature most characteristic of pernicious anemia is: A eosinophilia B toxic granulation C hypersegmentation D atypical lymphocytes
C hypersegmentation Macro-ovalocytes, teardrops, hypersegmentation, low WBC, and low platelets are seen in pernicious anemia. Pernicious anemia is a deficiency of vitamin B12 which impairs DNA synthesis.
In chronic myelocytic leukemia, blood histamine concentrations tend to reflect the A number of platelets present B serum uric acid concentrations C number of basophils present D total number of granulocytes
C number of basophils present
Polychromatic red cells when stained with a supravital stain are called A siderocytes B reticulocytes C schistocytes D spherocytes
B reticulocytes
Which of the following is seen most often in thalassemia? A chronic blood loss B target cells C basophilic stippling D ringed sideroblasts
B target cells
The best test to determine if a sample is contaminated with heparin is A fibrinogen B thrombin time C prothrombin time D stypven time
B thrombin time A prolonged thrombin time may be considered evident of diminished or abnormal fibrinogen, however, the presence of anti-thrombin activity, such as heparin, must be ruled out.
Which of the following is the formula for a manual WBC fluid cell count? A (number of cells counted x dilution x 10)/ number of squares counted B (number of cells counted x dilution)/ 10 x number of squares counted C number of cells counted x number of squares counted D number of cells counted x dilution
A ( number of cells counted x dilution x 10)/ number of squares counted This is hemacytometer calculation for counting cells in fluids
Which of is the formula for MCHC? A (Hgb x 100)/ Hct B Hgb/ RBC C RBC/Hct D (Hct x 100)/RBC
A (Hgb x 100)/Hct MCHC is the average concentration of hemoglobin per unit volume of RBCs.
The most common form of childhood leukemia is A acute lymphocytic leukemia B acute granulocytic C acute monocytic D chronic granulocytic
A acute lymphocytic leukemia ALL is the most common malignancy of children.
Plasma from a patient with lupus coagulation inhibitor can show: A prolonged APTT and normal PT B a prolonged thrombin time C no charge with platelet neutralization D complete correction when incubated with normal plasma
A prolonged APTT and normal PT Patients suspected of a lupus anticoagulant present with a prolonged APTT. Laboratory assays to detect lupus anticoagulant are the APTT, dilution Russel viper venom test, and Kaolin clotting time. In the presence of a lupus anticoagulant, the mixing study doesn't correct.
Elevation of the lymphocyte percentage above 47% is termed A relative lymphocytosis B absolute lyhocytosis C leukocytosis D absolute neutrophilic leukocytosis
A relative lymphocytosis Relative refers to the percentage. Absolute refers to the absolute count. Leukocytosis refers to the total WBC population, not the the sub-populations.
Supravital staining is important for reticulocytes since the cells must be living in order to stain the: A remaining RNA in the cell B iron before it precipitates C cell membrane before it dries out D denatured hemoglobin in the cell
A remaining RNA in the cell Using a supravital stain, residual ribosomal RNA is precipitated within the reticulocytes.
A sedimentation rate is set up 2 hours after the specimen is received by the laboratory. Ten minutes before the sedimentation rate is to be read, the technician notices that the tube was tilted. The technician should then A remix the blood and set up the procedure again B report the results after waiting 10 minutes C obtain a new specimen and set up the dedicate again D correct the sedimentation rate for the degree of the angle
A remix the blood and set up the procedure again
Normal platelets have circulating life-span of approximately A 5 days B 10 days C 20 days D 30 days
B 10 days The average life span of platelets in peripheral blood is 9.5 days.
A WBC count is 10.0 x 10^3 uL and 25 NRBCs are seen per 100 WBCs on the differential. What is the corrected WBC count? A 2.0 x 10^3 uL B 8.0 x 10^3 uL C 10.0 x 10^3 uL D 12.0 x 10^3 uL
B 8.0 x 10^3 uL Corrected WBC = (uncorrected WBC x 100)/100+ # of NRBCs per 100 WBCs. 10 x 100/100+ 25=8.0 x 10^3 uL.
Side angle scatter in a laser-based cell counting system is used to measure a. Cell size b. Cytoplasmic granularity c. Cell number d. Antigenic identification
B Cytoplasmic granularity Side angle scatter of a laser beam increases with granularity of the cytoplasm. Forward angle scatter is used to determine relative size. The number of signals is proportional to the munger of cells. The presence of specific antigens in the cytoplasm or on the cell surface is determined by immunofluorescence after reactions with appropriate antibodies.
Which of the following is associated with may-Heflin anomaly? A membrane defect of lysosomes B Dohle bodies and giant platelets C chronic myelogenous leukemia D mucopolysaccharidosis
B Dohle bodies and giant platelets
Which of the following red cell inclusions can be detected with a supravital preparation that uses new methylene blue N as the dye reagent but are not visible with Romanowsky stain? A Howell-Jolly bodies B Heinz bodies C Malarial trophozoites D Siderotic granules (Pappenheimer bodies)
B Heinz bodies There are only a few red cell inclusions that cannot be seen on Romanowsky stain. Heinz bodies, since they are composed of precipitated globin, have the same net charges as non-precipitated globin and therefore are not visible with a stain on acid-base principles.
Evidence indicates that the genetic defect in thalassemia usually results in A the production of abnormal globin chains B a quantitative deficiency in RNA resulting in decreased globin chain production C a structural change in the heme ration of the hemoglobin D An abnormality in the alpha or beta binding or affinity
B a quantitative deficiency in RNA resulting in decreased globin chain production
Platelet activity is affected by: A. calcium B. aspirin C. hyperglycemia D. hypoglycemia
B. Aspirin Aspirin interferes with prostaglandin metabolism in the platelet by inhibiting cyclooxygenase, which participates in the conversion of arachidonic acid to protein G2; protein G2 is necessary to produce thromboxane, which stimulates secretion from the platelet granules.
If a blood smear is dried too slowly, the red blood cells are often: A. clumped B. crenated C. lysed D. destroyed
B. crenated Prolonged drying of slides will produce erythrocyte distortion (crenated) on microscopic examination.
Which of the following technical factors will cause a decreased erythrocyte sedimentation rate? A gross hemolysis B small fibrin clots in the sample C increased room temperature D tilting of the tube
B. small fibrin clots in the sample When the shape or size of the red blood cells prevents rouleaux formation a decreased or low ESR is expected. This is observed with sickle cells, acanthocytes, and spherocytes.
The "rule of three" means that the: A MCV is three times the MCH B RBC count is three times the HGB C HCT is three times the HGB D HCT is three times the MCH
C HCT is three times the HGB In a healthy individual, the hematocrit in percent is roughly three times the hemoglobin values in g/dL, which is, in turn, roughly three times the RBC count (ignoring the power of 10). This "rule of three" can be used to evaluate the probable acceptance of CBC results quickly. If the rule of three does not apply to a given sample, it can indicate a patient abnormality or error in sample collection or testing.
Which of the RBC indices is a measure of the amount of hemoglobin in the individual red blood cells? A MCHC B MCV C Hct D MCH
D MCH Patients unable to synthesize normal amount of hemoglobin shown reduction in the MCH. The MCH, or mean cell hemoglobin, is a measure of the mass of hemoglobin by a red blood cell. The MCHC, or mean cell hemoglobin concentration, is a measure of the concentration of hemoglobin in a given volume of packed red blood cells. MCV, or mean cell volume, is a measure of cell size. Hematocrit is measure of the percentage of the volume of whole blood that is made up of red blood cells.
Which of the following are characteristic of polycythemia vera? A elevated urine erythropoietin levels B increased oxygen affinity of hemoglobin C "teardrop" poikilocytosis D decreased or absent bone marrow iron stores
D decreased or absent bone marrow iron stores
In normal adults, the spleen acts as a site for: A storage of red blood cells B production of red blood cells C synthesis of erythropoietin D removal of imperfect and aging cells
D removal of imperfect and aging cells The spleen is the major site of destruction of senescent red blood cells. RBCs Serra produced in the bone marrow. Erythropoietin is produced by interstitial fibroblasts in kidney.
50-90% myeloblasts in peripheral blood is typical of which of the following? A. chronic meylocytic leukemia B. myelofibrosis with myeloid metaplasia C. erythroleukemia D. acute myelocytic leukemia
D. acute myelocytic leukemia >20% of my Elo lasts without other immune stages differentiates AML from CML and myeloid meta plasma; erythroleukemia requires at least 50% erythroid precursors in marrow.
Heinz bodies are A readily identified with polychrome stains B rarely found in glucose 6 phosphate dehydrogenase deficient erythrocytes C closely associated with spherocytes D denatured hemoglobin inclusions that are readily removed by the spleen
D. denatured hemoglobin inclusions that are readily removed by the spleen
A differential was performed on an asymptomatic patient. The differential included 60% neutrophils: 55 of which had 2 lobes and 5 had 3 lobes. There were no other abnormalities. This is consistent with which of the following anomalies? A Pelger-Huet B May-Hegglin C Alder- Riley D Chediak-Higashi
A Pelger-Huet Pelegrín-Huet is a inherited disorder which may be misinterpreted as a shift to the left. Most neutrophils have round or bilobed nuclei with coarse, pyknotic condensation of the nucleus chromatin. Rod-like, dumbbell, and spectacle-like (prince-nez) nuclear shapes are common. Pseudo-Pelger-Huet may develop after considerable courses of chemotherapy have been administered.
What effect would the use of a buffer with pH of 6.0 have on a Wright stained smear? A RBCs would be too pink B WBCs would be well differentiated C RBCs would be too blue D RBCs would lyse
A RBCs would be too pink The pH of the buffer is critical in Romanowsky (Wright) stain. When the pH is too low (usually range is 6.4 - 6.7) the red cells take up more acid (eosin) and become too pink. Also, the white cells do not differentiate well, giving poor nuclear detail.
A 50 year old woman who has been receiving busalfan for3 years for chronic myelogenous leukemia becomes anemic. Laboratory test reveal: Thrombocytopenia Many peroxidase-negative blast cells in the peripheral blood Bone marrow hyper cellularity in blast transformation Markedly increased bone marrow TdT Which of the following complications is this patient most likely to have? A acute lymphocytic leukemia B acute myelocytic leukemia C acute myelomonocutic leukemia D busulfan toxicity
A acute lymphocytic leukemia
A build up of fluid in a body cavity is called: A an effusion B a transudate C an exudate D metastasis
A an effusion A small amount of fluid fills a cavity between the cavity wall (the parietal membrane) and the organ (visceral membrane). An increase in fluid can be due to inflammation, cancer, and defect in hypostatic and colloidal pressure. An accumulation of fluid is called an effusion.
The RDW performed by automated cell counters are calculations that provide: A an index of the distribution of RBC volumes B a calculated mean of RBC hemoglobin concentration C a calculated mean cell hemoglobin D the mean RBC volume
A an index of the distribution of RBC volumes Red cell distribution width (RDW) is a measurement of the variation in size of RBCs. Usually RBCs are a standard size of about 6-8 um. Certain disorders, however, cause a significant variation in cell size. Higher RDW values indicate greater variation in size. If anemia is observed, RDW results are often used together with MCV results to determine the possible causes of anemia. It is mainly used to differentiate an anemia of mixed causes from an anemia of a single cause.
Low molecular weight heparin is monitored by a A antiXa assay B APTT C PT D anti-IIa assay
A antiXa assay The chromogenic antiXa assay available to monitor low molecular weight heparin (LMWH). It may also be used to measure unfractionated heparin (UFH). The APTT can not be used to monitor LMWH therapy.
Specific (secondary) granules of the neutrophilic granulocyte A appear first at the myelocyte stage B contain lysosomal enzymes C are formed on the mitochondria D are derived from azurophil (primary) granules
A appear first at the myelocyte stage Azophilic granules are specialized lysosomes that stain dark blue. Specific (secondary) granules (neutrophilic, eosinophilic) change the color of the cytoplasm from basophilic to bluish-pink.
Which of the following results from decreased synthesis of goo in chains? A beta-thalassemia B hemoglobin C disease C hemoglobin Lepore syndrome D sickle cell disease
A beta-thalassemia Beta-thalassemia is correct. All other options result from structural abnormalities.
Which of the following detects or measures platelet function? A bleeding time B prothrombin time C thrombin time D partial thromboplastin time
A bleeding time The bleeding time test assesses platelet function. This test is a screening test where a precise cut is made on the surface of the arm and is timed to see how long it takes the bleeding to stop. The bleeding time test is subject to many variables and has been replaced by the PFA (Dade Plarelet Function Analyzer), VerifyNow Aspirin Resistance Test, and other platelet aggregation tests.
Excess D-dimer indicates that clots have been A converted to fibrin monomers B released into circulation C formed and are being excessively lyse D stimulated to active platelets
A converted to fibrin monomers D-dimers are produced from cross linked and stabilized fibrin clots. This clot is dissolved by plasma and d-diners are released. Therefore, d-dimers suggest a breakdown of fibrin clots, and indicate that clots have been formed at the site of injury.
A patient is diagnosed as having bacterial septicemia. Which of the following would best describe the expected change in his peripheral blood? A granulocytic leukemoid reaction B lymphocytic leukemoid reaction C neutropenia D eosinophilia
A granular leukemoid reaction In bacterial septicemia, the granulocytes will be increased to help fight infection through phagocytosis. Lymphocytes are often seen in viral infections rather than bacterial infections. Neutropenia is a decrease in neutrophils (granulocytes), and eosinophilia is commonly seen in allergic reactions and parasitic infections.
Which of the following test could be performed on a hemolyzed blood sample? A hemoglobin only B hemoglobin and platelet count C RBC count and hematocrit D no result would be reportable
A hemoglobin only Hemoglobin is valid on a hemolyzed specimen because RBC lysis is the first step in the cyanmethemoglobin method. The red blood cell count depends on the presence of intact red blood cells. Red blood cell fragments caused by hemolysis may be as small as platelets and affect instruments that use sizing criteria to differentiate the two. Therefore, samples for these procedures should be recollected.
A platelet determination was performed on an automated instrument and a very low value was obtained. The platelets appeared adequate when estimated from the stained blood film. The best explanation for this discrepancy is: A. many platelets are abnormally large B. blood sample is hemolyzed C. white cell fragments are present in the blood D. red cell fragments are present in the blood
A many platelets are abnormally large Instruments count particles within defined size limits. The upper limit is to separate large platelets from erythrocytes. Large platelets may be counted as erythrocytes.
The following results were obtained on a 45 year old man complaining of chills and fever WBC 23.0 x 10^3/uL Diff Segs 60% Bands 21% Lymphs 11% Monos 3% Metamyelos 2% Myelos 3% Toxic granulation, Dohle bodies, and vacuoles LAP 200 Philadelphia chromosome Negative These results are consistent with A neutrophilic leukemoid reaction B polycythemia Vera C chronic granular leukemia D leukoerythroblastosis in myelofibosis
A neutrophilic leukemoid reaction
The midnight shift received a sample with a prolonged aPTT of 56.2 seconds (normal=27.5-36.2 seconds), and the clinician requested it be frozen and saved for later testing. The plasma was removed and frozen within 4 hours. The sample was thawed for additional testing, and the aPTT was repeated. The result was 36.0 seconds. What could be possible reason for this change in aPTT value? A sample was not platelet poor B heparin contamination C ration of blood to anticoagulant D. Sample was too old
A sample was not platelet poor The sample may not have been platelet poor. Freezing and thawing could cause the platelets remaining in the plasma to burst. Platelets are a source of phospholipids, which would react with the reagents and shorten the aPTT test result. Heparin contamination would have prolonged both the original and the repeat aPTT. Freezing a heparinized sample would not change the result. If the ratio of blood to anticoagulant was not 9:1, the aPTT result would stay prolonged regardless of freezing or thawing. The sample was not too old; it was processed within the allowable four-hour window.
A 40 year old man had an erythrocyte count of 2.5 x 10^6, hematocrit of 22%, and a reticulocyte count of 2.0%. Which of the following statements best describes his condition. A the absolute reticulocyte count is 50 x 10^6/uL, indicating that bone marrow is not adequately compensating for the anemia. B the reticulocyte count is greatly increased, indicating an adequate bone marrow response for this anemia. C The reticulocyte count is 500 x 10^3/uL, indicating that the bone marrow is adequately compensating for the anemia. D the reticulocyte count is slightly increased, indicating an adequate response to slight anemia.
A the absolute reticulocyte count is 50 x 10^6/uL, indicating that bone marrow is not adequately compensating for the anemia.
A blue top tube was collected from a patient at a remote collection site at 8 AM. The test ordered is a prothrombin time (PT). The specimen will not be picked up by the testing laboratory's courier until noon, but the test will be completed within 24 hours. How should the specimen be stored until it is picked up by the courier? A the tube should remain unopened and be kept at room temperature (18-24 degrees Celsius) B the specimen cannot be stored; it must be tested immediately C the tube should be opened and the plasma should be removed and refrigerated D the tube should be centrifuged but remain unopened and frozen at -20 degrees Celsius
A the tube should remain unopened and be kept at room temperature (18-24 degrees Celsius) Blood collected for prothrombin time (PT) test that will be completed within 24 hours of collection should remain in the unopened blood collection tube. Room temperature storage (18-24 degrees Celsius) is recommended. Temperatures between 2-4 degrees Celsius may result in cold activation of factor VII that would alter the PT result. The tube should not be opened to remove the plasma prior to testing if the test will be completed within 24 hours of collection. Plasma should be removed and frozen at -20 degrees Celsius or lower if the PT test will not be completed within 24 hours. However, whole blood should never be frozen because the red cells will lyse and the PT test result would be drastically altered.
The following results are obtained on a 55 year old man complaining of headaches and blurred vision: WBC 19.0 x 10^3uL RBC 7.2 x 10^6 uL Plt 1,056 x 10^3 uL Segs 84% Bands 10% Lymph's 3% Monos 2% Eos 1% The results are consistent with: A neutrophilic leukemoid reactions B polycythemia Vera C chronic myeloytic leukemia D leukoerythroblastosis in myelofibrosis
B polycythemia Vera These results reflect polycythemia Vera's excessive proliferation of multiphasic cell lines (megakaryocytes, erythroid, and myelocytoid).
The light-colored zone adjacent to the nucleus in a plasmacyte is the: A ribosome B chromatin C mitochondria D golgi area
B chromatin The mature plasma cell has a perfectly round or oval nuclear shape with persistent granular chromatin clumps throughout the nucleus. The nucleus is frequently located at the edge of the cell. The light colored zone, or perinulear halo, is the cellular organelle which produces and packages protein for secretion.
Hemolysis in paroxysmal nocturnal hemoglobinuria (PNH) is A temperature dependent B complement dependent C antibody mediated D caused by red cell membrane defect
B complement dependent
What does the international normalized ratio (INR) represent? A the sensitivity of the reagent B correction of the PT regardless of instrument/reagent combination C a result that should always be used in place of the number of seconds as the PT result D a result that is the correction of PT when incubated with normal plasma
B correct in of the PT regardless of instrument/reagent combination The INR represents a correction of the PT regardless of instrument/reagent combination and is used for standardization of prothrombin time (PT) results. The sensitivity of the reagent is the international sensitivity index (ISI). The ISI is a number provided by the manufacturer of a prothrombin time reagent that denotes how sensitive the reagent is to decreased levels of the vitamin K dependent factors. The most sensitive reagent is assigned an ISI of 1; all other reagents are compared to this standard. The ISI is used to determine the INR. The patient's PT result is divided by the geometric mean and then multiplied exponentially by the assigned ISI. INR=(PT of patient/PT of the geometric mean normal population)^ISI. The INR is not always used in place of the PT; it is only used for a patient that is on a stabilized dose of warfarin.
The following results were obtained on an electronic particle counter: WBC 6.5 x 10^3 uL RBC 4.55 x 10^3 uL Hgb 18.0 g/dL Hct 41.5% MCV 90.1 fL MCH 39.6 pg MCHC 43.4% The first step in obtains valid results is to: A perform a micro hematocrit B correct the hemoglobin for lipemia C dilute the blood D replace the losing agent
B correct the hemoglobin for lipemia The HGB is falsely high indicated by the "rule of three" where RBC x 3=Hgb and Hgb x3=Hct. The MCH and MCHC are also high. Falsely high Hgb values are commonly caused by lipemia.
The internationally accepted method of hemoglobin measurement requires the conversion of hemoglobin to: A carboxyhemoglobin B cyanmethemoglobin C oxyhemoglobin D sulfhemoglobin
B cyanmethemoglobin Hemoglobin in the circulation is normally found in several forms, including oxyhemoglobin, de oxyhemoglobin, carb oxyhemoglobin, and methemoglobin. Each of these compounds has a separate peak absorbance and is therefore measured spectrophotometrically at different wavelengths. Conversion of these forms of hemoglobin to methemoglobin (oxidation of Fe+2 to Fe +3) and reaction of the methemoglobin with KCN to form cyanmethemoglobin (hemiglobincyanide) results in a stable compound that can be measured spectrophotometrically at 540 nm. The only form of hemoglobin found in the circulation that will not form cyanmethemoglobin is sulfhemoglobin, which, except in rare cases, is present only in very small amounts.
Which of the following sets laboratory findings in consistent with hemolytic anemia? A normal or slightly increased erythrocyte survival; normal osmotic fragility B decreased erythrocytes survival; increased catabolism of heme C decreased serum lactose dehydrogenase activity; normal catabolism of heme D normal concentration of haptoglobin; marked hemoglobinuria
B decreased erythrocytes survival; increased catabolism of heme
Which of the following is most closely associated with acute promyelocytic leukemia? A ringed sideroblasts B disseminated intravascular coagulation C micromegakaryocytes D Philadelphia chromosome
B disseminated intravascular coagulation DIC
Phagocytosis is a function of A erythrocytes B granulocytes C lymphocytes D thrombocytes
B granulocytes Granulocytes are the principle leukocyte associated with phagocytosis and localized inflammatory response. Erythrocytes transport oxygen via hemoglobin, lymphocytes provide immunity, both cell-mediated and immunoglobulin. Thrombocytes (platelets) are involved in hemostasis (blood clotting functions).
Bone marrow cellularity refers to a ratio of A red cell precursors to white cell precursors B hematopoietic tissue to adipose tissue C granulocytic cells to erythrocytes cells D extra vascular tissue to intra vascular tissue
B hematopoietic tissue to adipose tissue Bone marrow cellularity in the normal adult is approximately 50% hematopoietic tissue and 50% adipose tissue(fat) with a range of 30-70% cellularity being normocellular. Marrow cellularity is usually estimated from core biopsy. An intact bone marrow can respond to demand by increasing its activity several times the normal rate if sufficient supplies and growth factors are available. The marrow becomes hypercellular when inactive fatty tissue is replaced by active hematopoietic marrow. In contrast, bone marrow failure may result in hypo cellularity or aplasia with increased fat and a reduced number of hematopoietic cells.
The term "shift to left" refers to A a microscope adjustment B immature cell forms in the peripheral blood C a trend on Levy-Jennings chart D a calibration adjustment on an instrument
B immature cell forms in the peripheral blood In the presence of systemic infection, neutrophils increase to >70% of the WBC population in the blood. This triggers a large release into the circulating compartment. Neutrophils are then released from the bone marrow at an earlier stage of development. Left shift -increased number of band cells where the cell nuclei are C- shaped.
Multiple myeloma is generally characterized by A plasmacytic satellitosis in the bone marrow B many plasma cells on the peripheral blood C many Mott cells in the peripheral blood D rouleaux formation
B many plasma cells on the peripheral blood
Auer rods are A normal aggregation of lysosomes or primary (azurophilic) granules B predominantly found in acute myelogenous leukemia C peroxidase negative D alkaline phosphate positive
B predominantly found in acute myelogenous leukemia
A platelet count is performed on an automated instrument from an EDTA blood sample. Smear evaluation reveals the presence of platelet clumps. The specimen is redrawn using sodium citrate as the anticoagulant, and a count of 300 x 10^3 uL is obtained. What is the correct platelet count to report? A 270 x 10^3 uL B 300 x 10^3 uL C 330 x 10^3 uL D 360 x 10^3 uL
C 330 x 10^3 uL Some patients develop EDTA-dependent platelet agglutinins caused by an IgM or IgG platelet-specific antibody. To correct for this, the sample can be redrawn in sodium citrate and rerun. The dilution factor of blood to anticoagulant sodium citrate is 9:1. To compensate for 10% dilutional loss of platelets,the platelet count obtained must be multiplied by 1.1. 300 x 11= 330 x 10^3 uL.
A patient who is not taking any anticoagulant medication has the following PT and aPTT results PT=17.1 seconds ( normal 10.2-13.2 seconds) aPTT = 35.5 seconds (normal = 27.5-36.2 seconds) What is a likely cause for the prolonged PT? A heparin contamination B Factor X deficiency C Factor VII deficiency D improperly filled tube
C Factor VII deficiency The PT is exclusive for factor VII in the extrinsic pathway. A factor VII deficiency is the most likely cause for these test results. Additional testing, such as mixing studies and factor assays, would be needed to confirm this. The aPTT would be prolonged if heparin was present in the sample. Factor X is part of the common pathway. If it were deficient, the aPTT would also be prolonged. The aPTT is more sensitive to improperly filled tubes, and in case the aPTT result is normal.
Coagulation factors affected by warfarin (Coumadin) drugs are A VII, IX, and X B I, II, V, and VII C II, VII, IX, and X D II, V, and VII
C II, VII, IX, and X Warfarin interferes with the carboxylation of vitamin K factors by interrupting the enzymatic phase of the reaction. Factor are inhibited according to their half life, VII having the softest (4-5 hours) and II the longest (2-3 days).
The most appropriate screening test for hemoglobin F is: A osmotic fragility B dithionite solubility C Kleihauer- Betke D heat instability test
C Kleihauer-Betke The Kleihauer-Betke procedure is commonly used as a screening test to determine the amount of fetal blood that has mixed with maternal blood.
Hairy cell leukemia (leukemic reticuloendotheliosis) is A an acute myelocytic leukemia B a chronic leukemia of myelocytic origin C a chronic leukemia of lymphocytic origin D an acute myelocytic monocytic-type leukemia
C a chronic leukemia of lymphocytic origin
The characteristic morphology features in lead poisoning is A macrocytosis B target cells C basophilic stippling D rouleaux formation
C basophilic stippling Basophilic stippling is aggregation of RNA (ribosomes) found in exposure to lead, accelerated or abnormal hemoglobin synthesis, and thalassemia.
Of the following, the disease most closely associated with pale blue inclusions in granulocytes and giant platelets is A Guacher disease B alder-reilly anomaly C may-hegglin anomaly D pelger-huet anomaly
C may-hegglin anomaly These are primary characteristics distinguishing may-haggling from other neutrophil and lipid storage anomalies.
The largest hematopoietic cells in normal bone marrow are: A osteoblasts B osteoclasts C megakaryocytes D plasma cells
C megakaryocytes The mature megakaryocyte, the largest hematopoietic cell in the normal bone marrow, has a multilobed nucleus and abundant, granular cytoplasm. Plasma cells are characterized by a round, eccentric nucleus and intensely blue cytoplasm. Osteoblasts and osteoclasts are involved in bone formation that resemble plasma cells but are larger and often found in groups. Osteoclasts reabsorb bone and are similar to megalaryocytes in size but are multinucleated.
Which of the following is used for staining reticulocytes: A Giemsa stain B Wright stain C new methylene blue D Prussian blue
C new methylene blue Using a supravital stain (new methylene blue) , residual ribosomal RNA is precipitated within the reticulocytes.
In the APTT test, the patient's plasma is mixed with: A ADP and calcium B tissue thromboplastin and collagen C phospholipids and calcium D tissue thromboplastin and calcium
C phospholipids and calcium The APTT reagent contains phospholipids and a negatively-charged particulate activator such as kaolin, ellagic acid, or Celite. Ionic calcium and phospholipids are supplied as reagents.
The following values were plotted during the first six days of new lot of control for WBC count determination using an electronic particle counter. 7.4, 7.3, 7.2, 7.1, 7.0, 6.9, 6.8, 6.7, 6.6, 6.5 The coefficient of variation (CV) is 3.5%. Assume that these results representative of the laboratory's usual performance of WBC counts in the normal and low ranges. Evaluation of the statistical pattern and the coefficient of variation indicate that: A corrective active is unnecessary since the CV and plotted data are acceptable B a dilutor check is necessary C the control may be deteriorating D calculation of new mean and standard deviation is necessary
C the control may be deteriorating Continuously increasing variation in one direction points to a segment, a control/sample, or an instrument problem. If drift were upward one would suspect a dilutor error. In this instance the drift is downward; therefore the more likely factor is deterioration of the control. Other possibilities are reagent deterioration and an electronic problem with the counting instrument.
A specimen run on an automatic cell counter has a platelet count of 19 x 10^3/uL (19 x 10^9/L). The first thing the technician should do is: A. report the count after the batch run is completed B. request a new specimen C. review the stained blood smear D. notify the laboratory manager
C. review the stained blood smear Low platelet count values should be verified with a slide estimate.
A 4 year old patient presents to the emergency department (ED) with hematuria and a family history of bleeding disorders. The patients coagulation test results are given below. What is a possible cause of the prolonged aPTT? PT 11.9 sec ( normal = 10.2-13.2 seconds) aPTT 52.1 sec ( normal = 27.5-36.2 seconds) Thrombin Time 11.2 sec (normal =10.1-19.0 seconds) Hematocrit 35.4% (34.0-40.0%) A Factor V deficiency B concentration of RBCs C heparin contamination D Factor VII deficiency
D Factor VII deficiency Factor VII deficiency is a possible cause of prolonged aPTT. The PT is normal, and the aPTT is abnormal. Therefore, possibilities include factor VII, XI, or IX deficiency. Factor V is measured in the common pathway and both the PT and the aPTT would be prolonged if factor V deficiency was the cause. The best test to demonstrate residual heparin is the thrombin time. If heparin were present, the thrombin time would be prolonged. A high HCT (>55%) can cause a prolongation of the aPTT because of the increased ratio of anticoagulant to plasma. In this case, however, the HCT is normal and the concentration of RBCs (as represented by the HCT) is not the cause of the prolonged aPTT.
After gentle inversion of tube #1 of freshly collected cerebrospinal fluid specimen, the specimen appeared slightly turbid (1+) and pale yellow. After centrifugation the supernatant was clear and yellow. Which of the following statements is correct? A methemoglobin is present B a traumatic tap has occurred C free hemoglobin is present D pathogenic bleeding has occurred
D pathogenic methemoglobin is present the supernatant is brown. The supernatant is colorless after a traumatic tap, and a recent hemorrhage into the subarachnoid space will result in hemolysis and the reals of free hemoglobin; as a result, the supernatant will be pinkish. Xanthochromia, or yellow color, results from the breakdown of hemoglobin into bilirubin. It suggests bleeding into the subarachnoid space within the last two or three weeks.
Multiple myeloma may be suspected if which of the following is seen on a peripheral smear? A basophilic stippling B bizarre last cells C hypersegmented neutrophils D rouleaux
D rouleaux Rouleaux due to increased plasma protein (monoclonal immunoglobulin) may be seen in multiple myeloma. The serum viscosity is increased and the albumin:globulin ratio is decreased. Option A is seen in conditions associated with disturbed erythropoiesis. Option B is seen in leukemia states. Option C is seen in pernicious anemia.
To avoid falsely elevated spinal cell fluids A use an aliquot from the first tube collected B use only those specimens showing no turbidity C centrifuge all specimens before counting D select an aliquot from the last tube collected
D select an aliquot from the last tube collected The lumber tap may be traumatic, which will produce blood. Blood cells in the CSF will not be due to a central nervous system defect in that case. Do the cell count on the last tube; it is least likely to be contaminated by a bloody tap.
The physician questions an abnormal aPTT result of 67 seconds(normal =27.5-36.2 seconds) that is received on a patient with polycythemia vera whose hematocrit is 70%. The patient is not on heparin and is not bleeding. The specimen was obtained by venipuncture using a blood collection tube containing 3.2% sodium citrate. The tube was adequately filled and no clots were in the specimen. What may be the reason for the prolonged aPTT? A 3.2% citrate is not the correct anticoagulant to use for plasma based coagulation tests B there is insufficient anticoagulant in the blood collection tube C the blood collection tube may have been expired D there is too much anticoagulant for the amount of plasma in the blood specimen.
D there is too much anticoagulant for the amount of plasma in the blood specimen. There is too much anticoagulant for the amount of plasma in the blood specimen. Sodium citrate anticoagulant distributes only in the plasma and not into the blood cells. For this reason, plasma citrate concentration will be increased if the patient's hematocrit is greater than 55%, leading to prolonged aPTT and PT results. If possible, the sodium citrate concentration should be adjusted based on the patient's hematocrit value, and the specimen should be recollected. An expired blood collection tube could cause the tube to under fill or the anticoagulant to be ineffective, but the tube was adequately filled and no clots were noted in the specimen.
