10 Flashcards
- Which of the following blood specimen conditions would not cause a falsely elevated concentration with a manually performed cyanmethemoglobin determination?
A. Lipemia
B. Extremely elevated WBC count
C. Hemoglobin S
D. Hemoglobin F
D. Hemoglobin F
- If a patient has a microhematocrit of 36% and a hemoglobin value of 11.5 g/dL, the “rule of three” calculation would be ________ plus or minus (3).
A. 108
B. 47.5
C. 34.5
D. 14.5
C. 34.5
- The formula for MCV is
A. packed cell volume or hematocrit (in L/L)/ erythrocyte count (×1012/L) = fL
B. hemoglobin (in g/dL)/packed cell volume or hematocrit (in L/L) = g/dL
C. hemoglobin (×10 g/dL)/erythrocyte count (×1012/L) = pg
D. microhematocrit × 3 = percent
A. packed cell volume or hematocrit (in L/L)/ erythrocyte count (×1012/L) = fL
- The formula for MCH is
A. packed cell volume or hematocrit (in L/L)/ erythrocyte count (×1012/L) = fL
B. hemoglobin (in g/dL)/packed cell volume or hematocrit (in L/L)
= g/dL
C. hemoglobin (×10 g/dL)/erythrocyte count (×1012/L) = pg
D. microhematocrit × 3 = percent
C. hemoglobin (×10 g/dL)/erythrocyte count (×1012/L) = pg
The formula for MCHC is
A. packed cell volume or hematocrit (in L/L)/ erythrocyte count (×1012/L) = fL
B. hemoglobin (in g/dL)/packed cell volume or hematocrit (in L/L) = g/dL
C. hemoglobin (×10 g/dL)/erythrocyte count (×1012/L) = pg
D. microhematocrit × 3 = percent
B. hemoglobin (in g/dL)/packed cell volume or hematocrit (in L/L) = g/dL
If an MCHC result of 40 g/dL is discovered in a patient’s instrumentation printout, what is a possible cause?
A. Increased RDW
B. Hypochromic RBCs
C. Agglutinated RBCs
D. Increased number of RBC fragments
C. Agglutinated RBCs
If a patient specimen is slightly hemolyzed, which of the RBC indices would be most affected?
A. MCV
B. MCH
C. MCHC
D. Reticulocyte count
B. MCH
- What hematology test is useful in monitoring the production of erythrocytes?
A. Total iron binding capacity
B. Ferritin level
C. Reticulocyte count
D. Hemoglobin
C. Reticulocyte count
- The normal range for reticulocytes in adults is
A. 0% to 0.5%
B. 0.5% to 1.0%
C. 0.5% to 2.5%
D. 1.5% to 2.5%
C. 0.5% to 2.5%
- If a male patient has a reticulocyte count of 5.0% and a packed cell volume of 0.45 L/L, what is his corrected reticulocyte count?
A. 2.5%
B. 4.5%
C. 5.0%
D. 10%
C. 5.0%
- If a male patient has a reticulocyte count of 6.0% and a packed cell volume of 45%, what is his RPI?
A. 1.5
B. 3.0
C. 4.5
D. 6.0
D. 6.0
- What is the appropriate reagent for the reticulocyte count?
A. New methylene blue.
B. Phyloxine B.
C. Solution lyses erythrocytes and darkens the cells to be counted.
D. Any laboratory acid.
A. New methylene blue.
- On a Wright-stained peripheral blood smear, stress or shift reticulocytes are
A. smaller than normal reticulocytes
B. about the same size as normal reticulocytes
C. larger than normal reticulocytes
D. noticeable because of a decreased blue tint
C. larger than normal reticulocytes
If a 40-year-old female patient had a corrected reticulocyte count of 8%, what would you expect to encounter on the peripheral blood smear stained with Wright stain?
A. Polychromatophilia
B. Poikilocytosis
C. >10 nucleated red blood cells/100 WBC
D. An increased estimated total platelet count
A. Polychromatophilia
- The reference value for the reticulocyte count in a newborn infant
is
A. up to 13 mm/hour
B. 2.5% to 6.5%
C. 150 to 450 × 109/L
D. 36% to 45%
B. 2.5% to 6.5%
- An anticoagulated blood specimen was diluted 1:20 dilution with 3% glacial acetic acid. If a total of 150 cells was counted in the appropriate four large corner squares of a hemacytometer, what is the patient’s total WBC count (×109/L)?
A. 1.5
B. 3.0
C. 5.0
D. 7.5
D. 7.5
- The reference value for total leukocyte count is
A. up to 13 mm/hour
B. 2.5% to 6.0%
C. 150 to 450 × 10^9/L
D. 4.5 to 11.0 × 10^9/L
D. 4.5 to 11.0 × 10^9/L
- What clinical or specimen condition will produce an increased total leukocyte count?
A. Active allergies
B. Immediate hypersensitivity reactions
C. Inflammation
D. A lipemic blood specimen
C. Inflammation
- What clinical condition will produce an increased value of neutrophils?
A. Invasive parasites
B. Bacterial infections
C. Viral infections
D. Tuberculosis
B. Bacterial infections
- What clinical condition will produce an increased value of lymphocytes?
A. Invasive parasites
B. Bacterial infections
C. Viral infections
D. Tuberculosis
C. Viral infections
- What clinical condition will produce an increased value of eosinophils?
A. Invasive parasites
B. Bacterial infections
C. Viral infections
D. Tuberculosis
A. Invasive parasites
- If the results of WBC count and differential smear were as follows for a 45-year-old female patient, what condition would the results represent?
WBC 5.6 × 109/L differential: segmented neutrophils 22%, lymphocytes 56%, monos 18%, eosinophils 4%.
A. Leukopenia
B. Absolute neutropenia
C. Relative neutrophilia
D. Absolute lymphocytosis
B. Absolute neutropenia
- What is the absolute count if a patient’s total WBC is 2.6 × 109/L with 30% lymphocytes?
A. 2.6 x 10^9/L
B. 2.0 x 10^9/L
C. 1.3 x 10^9/L
D. 0.78 x 10^9/L
D. 0.78 x 10^9/L
- What is the formula for calculating a manual white blood cell count?
A. Average total of leukocytes counted × dilution factor × volume correction
B. Average total of leukocytes counted × dilution factor ×
10/number of squares counted
C. Average total of leukocytes counted × dilution factor
D. Average total of leukocytes counted × number of squares counted
A. Average total of leukocytes counted × dilution factor × volume correction
A defect in leukocyte adhesion defect (LAD), can lead to
A. decreased cell locomotion
B. increased cell locomotion
C. decreased cellular killing capacity
D. increased cellular killing capacity
A. decreased cell locomotion
The LAP test is helpful in
A. differentiating malignant disorders from leukemoid reactions.
B. differentiating acute and chronic leukemias
C. diagnosing sickle cell anemia
D. detecting platelet dysfunctions
A. differentiating malignant disorders from leukemoid reactions.
- The ESR is a nonspecific indicator of disease with increased sedimentation of erythrocytes in
A. infections
B. inflammation
C. tissue necrosis
D. all of the above
D. all of the above
- The reference value for the Westergren ESR method for adult male less than 50 years of age) is
A. 0 to 10 mm/hour
B. 2.5% to 6.0%
C. 150 to 450 × 109/L
D. 36% to 45%
A. 0 to 10 mm/hour
- The correct dilution of blood for a manual platelet count is
A. 1:10
B. 1:20
C. 1:100
D. 1:200
C. 1:100
- When calculating the total platelet count of a blood specimen that has been diluted at a 1:100 dilution, the calculation should ______________ of the appropriate areas of the Neubauer counting chamber.
A. average the total number of platelets counted on both sides
B. use only the number of platelets counted on one side
C. add the total number of platelets counted on both sides
D. subtract the number of platelets counted on one side from the other side
A. average the total number of platelets counted on both sides
- The normal reference value for a direct platelet count is
A. up to 13 mm/hour
B. 2.5% to 6.0%
C. 150 to 450 × 109/L
D. 4.4 to 11.3 × 109/L
C. 150 to 450 × 109/L
- If a small blood clot exists in an anticoagulated blood specimen, which blood cell parameter will be affected the most?
A. Leukocyte count
B. Erythrocyte count
C. Platelet count
D. Microhematocrit
C. Platelet count
If platelet clumping was observed by direct observation of a stained peripheral blood smear and/or indicated by the output of an automated instrument, what corrective action can be taken?
A. Retrieve the patient specimen and prepare a new blood smear.
B. Retrieve the patient specimen and warm it up to 37°C for 15 minutes and reanalyze.
C. Recollect a new EDTA-anticoagulated specimen and promptly examine the platelets.
D. Recollect a new citrate anticoagulated specimen and reexamine the platelets.
D. Recollect a new citrate anticoagulated specimen and reexamine the platelets.
- If the identification of platelets by direct visualization using a phase microscope is problematic, what strategy can be taken to possibly improve seeing the platelets?
A. Be sure that the annular ring is centered to the phase ring.
B. Lower the condenser.
C. Carefully refocus with the fine adjustment knob of the microscope.
D. Close the iris diaphragm to reduce illumination.
B. Lower the condenser.
- If you are grading changes in erythrocytic size or shape using a scale of 0 to 4+ and many erythrocytes deviate from normal per microscopic field, the typical score would be
A. 1+
B. 2+
C. 3+
D. 4+
C. 3+
- Rouleaux appears as _____________ when examining a blood smear microscopically.
A. hollow red blood cells
B. polychromatophilia
C. a roll of stacked coins
D. larger than normal RBCs
C. a roll of stacked coins
- Semi-quantitative estimation of a leukocyte count generated by an automated instrument can
A. Confirm a low count
B. Confirm a high count
C. Substitute for an actual count
D. Indicate if the dilution of the whole blood was correct
C. Substitute for an actual count
A normal blood smear should have no more than approximately _____ (maximum) number of platelets per oil immersion field in an area where the erythrocytes are just touching each other.
A. 10
B. 15
C. 20
D. 25
C. 20
Ten fields on a properly prepared and stained peripheral blood smear were examined to estimate the quantitative total number of platelets. In these ten fields, the following observations were made: 10, 12, 10, 15, 17, 12, 14, 15, 11, 10. In correlating this semiquantitative assessment with the actual quantitative total platelet count measured by an automated instrument, you would expect to see a total platelet count around ________ 109/L.
A. 90
B. 130
C. 250
D. 400
C. 250
- If a febrile, newborn infant had 4 nucleated red blood cells when a 100 cell WBC differential was performed, how would this be interpreted?
A. Lymphocytes were mistaken for nucleated red blood cells.
B. The baby was suffering from hemolytic disease of the fetus and newborn (HDFN).
C. Nucleated red blood cells can be expected in febrile patients.
D. During the first few days of life, the presence of a few nucleated red blood cells is normal.
D. During the first few days of life, the presence of a few nucleated red blood cells is normal.
- If a total white blood cell count is 25.0 × 109/L and 50 nucleated red blood cells were counted per 100 leukocytes in the differential count, what is the corrected total white blood cell count?
A. 5.0 × 109/L
B. 7.5 × 109/L
C. 16.7 × 109/L
D. No correction needed
D. No correction needed
If a cell observed on a stained peripheral blood smear is 12 to 16 μm with abundant, muddy gray cytoplasm, a kidney bean–shaped nucleus with lacey chromatin, and no nucleoli, what type of cell is this?
A. Lymphocyte
B. Monocyte
C. Segmented neutrophil
D. Band neutrophil
B. Monocyte
