Question 1

What are the two main metabolic pathways that erythrocytes use to break down glucose?

Accepted Answer

A)  Glycolytic and hexose monophosphate shunt 
B)  Glycolytic and Luebering-Rapoport pathway 
C)  Krebs cycle and electron transport system 
D)  Hexokinase and Krebs cycle 
A)  Glycolytic and hexose monophosphate shunt 
B)  Glycolytic and Luebering-Rapoport pathway 
C)  Krebs cycle and electron transport system 
D)  Hexokinase and Krebs cycle A

Question 2

Explain the principle of each of the following tests.
a. Fluorescent spot test
b. Dye reduction test
c. Ascorbate cyanide test
d. Rate reduction test

Accepted Answer

a. Fluorescent spot test: Whole blood is added to a mixture of G6P, NADP, and saponin. G6PD enzyme metabolizes G6P and produces NADPH (which fluoresces). NADP does not. Lack of fluorescence indicates G6PD deficiency.
b. Dye reduction test: similar to fluorescent spot test except for indicator: blue color to colorless → presence of G6PD; blue color remains → absence of G6PD.
c. Ascorbate cyanide test: nonspecific test. Tests the ability of RBC catalase to inhibit hydrogen peroxide formation. G6PD-deficient patients allow hydrogen peroxide to form, which promotes the formation of methemoglobin. The presence of methemoglobin turns the solution brown.
d. Rate reduction test: Measures rate of conversion of NADP to NADPH via spectrophotometry at 340 nm.

Question 3

Female heterozygotes for G6PD deficiency have one population of cells that is normal and one that is G6PD deficient because:

Accepted Answer

A)  There is random inactivation of one X chromosome 
B)  There is random inactivation of one Y chromosome 
C)  There is random activation of one X chromosome 
D)  There is random activation of one Y chromosome 
A)  There is random inactivation of one X chromosome 
B)  There is random inactivation of one Y chromosome 
C)  There is random activation of one X chromosome 
D)  There is random activation of one Y chromosome A

Question 4

G6PD deficiency was first recognized during the Korean War when which of the following drugs were administered to the soldiers?

Accepted Answer

A)  Sulfonamides 
B)  Nitrofurans 
C)  Analgesics 
D)  Antimalarials 
A)  Sulfonamides 
B)  Nitrofurans 
C)  Analgesics 
D)  Antimalarials

Question 5

Increased bilirubin in the blood of infants can lead to ________ and is seen in ________.

Accepted Answer

A)  Hemoglobinuria; acute, acquired hemolytic anemia 
B)  Hemosiderinuria; congenital, nonspherocytic hemolytic anemia 
C)  Kernicterus; neonatal hyperbilirubinemia 
D)  Kernicterus; congenital, nonspherocytic hemolytic anemia 
A)  Hemoglobinuria; acute, acquired hemolytic anemia 
B)  Hemosiderinuria; congenital, nonspherocytic hemolytic anemia 
C)  Kernicterus; neonatal hyperbilirubinemia 
D)  Kernicterus; congenital, nonspherocytic hemolytic anemia

Question 6

For proper diagnosis of G6PD deficiency, timing of the testing is critical. When should it occur?

Accepted Answer

A)  Several months after a hemolytic attack 
B)  Within a week after a hemolytic attack 
C)  During compensatory reticulocytosis 
D)  After transfusion therapy 
A)  Several months after a hemolytic attack 
B)  Within a week after a hemolytic attack 
C)  During compensatory reticulocytosis 
D)  After transfusion therapy

Question 7

What is the purpose of the HMP shunt, and why is it important?

Accepted Answer

Its purpose is to maintain an

Question 8

Which of the following does not support the diagnosis of G6PD deficiency?

Accepted Answer

A)  Presence of Heinz bodies with new methylene blue stain 
B)  Reticulocytosis 
C)  Hemolytic morphology during oxidative event 
D)  Decreased mean cell volume 
A)  Presence of Heinz bodies with new methylene blue stain 
B)  Reticulocytosis 
C)  Hemolytic morphology during oxidative event 
D)  Decreased mean cell volume

Question 9

What metabolic pathway catabolizes approximately 10% of the glucose essential for maintaining adequate concentrates of reduced glutathione?

Accepted Answer

A)  Glycolytic pathway 
B)  Metabolic pathway 
C)  Hexose-monophosphate shunt 
D)  Nucleotide pathway 
A)  Glycolytic pathway 
B)  Metabolic pathway 
C)  Hexose-monophosphate shunt 
D)  Nucleotide pathway

Question 10

Which molecule is responsible for the neutralization of harmful peroxides?

Accepted Answer

A)  G6P 
B)  Glutathione 
C)  HK 
D)  PK 
A)  G6P 
B)  Glutathione 
C)  HK 
D)  PK

Question 11

In PK deficiency there is a loss of ________, which causes failure of the cation pumps in the RBC.

Accepted Answer

A)  G6PD 
B)  PEP 
C)  Glucose 
D)  ATP 
A)  G6PD 
B)  PEP 
C)  Glucose 
D)  ATP

Question 12

Which G6PD variant has normal activity and no hemolysis present?

Accepted Answer

A)  G6PD-Mediterranean 
B)  Minnesota 
C)  Iowa 
D)  G6PD-B 
A)  G6PD-Mediterranean 
B)  Minnesota 
C)  Iowa 
D)  G6PD-B

Question 13

A 53-year-old Italian male was hospitalized with increased fatigue and hemoglobinuria. Patient history revealed his last ingested meal contained fava beans. G6PD levels were performed 3 months later, and the result was 5%. Based on these findings, which class of G6PD variant is most likely affected?

Accepted Answer

A)  Class I 
B)  Class II 
C)  Class III 
D)  Class IV 
A)  Class I 
B)  Class II 
C)  Class III 
D)  Class IV

Question 14

Class IV G6PD enzymes include which of the following?

Accepted Answer

A)  G6PD-Mediterranean 
B)  G6PD-B and G6PD-A+ 
C)  G6PD-Iowa 
D)  G6PD-Canton 
A)  G6PD-Mediterranean 
B)  G6PD-B and G6PD-A+ 
C)  G6PD-Iowa 
D)  G6PD-Canton

Question 15

Intrinsic erythrocyte enzyme deficiencies lead to:

Accepted Answer

A)  Increased erythrocyte oxidative susceptibility 
B)  Exacerbated immune response against erythrocytes 
C)  Increased opsonization of erythrocytes 
D)  Increased extravascular hemolysis 
A)  Increased erythrocyte oxidative susceptibility 
B)  Exacerbated immune response against erythrocytes 
C)  Increased opsonization of erythrocytes 
D)  Increased extravascular hemolysis

Question 16

All of the following support the diagnosis of G6PD deficiency except:

Accepted Answer

A)  Presence of Heinz bodies with new methylene blue stain 
B)  "Bite cells" 
C)  Hemolytic morphology during oxidative event 
D)  Reticulocytopenia 
A)  Presence of Heinz bodies with new methylene blue stain 
B)  "Bite cells" 
C)  Hemolytic morphology during oxidative event 
D)  Reticulocytopenia

Question 17

What morphologic characteristics are found on a blood smear in G6PD deficiency?

Accepted Answer

A)  Leukopenia and echinocytes 
B)  Thrombocytopenia and reticulocytosis 
C)  Reticulocytosis and blister cells 
D)  Döhle bodies and Heinz bodies 
A)  Leukopenia and echinocytes 
B)  Thrombocytopenia and reticulocytosis 
C)  Reticulocytosis and blister cells 
D)  Döhle bodies and Heinz bodies

Question 18

Why are echinocytes seen in PK deficiency?

Accepted Answer

PK deficiency impairs the production of

Question 19

Which of the following is a quantitative test for G6PD?

Accepted Answer

A)  Fluorescent spot test 
B)  Quantitative NADP rate reduction test 
C)  NADP dye reduction test 
D)  Ascorbate cyanide test 
A)  Fluorescent spot test 
B)  Quantitative NADP rate reduction test 
C)  NADP dye reduction test 
D)  Ascorbate cyanide test

Question 20

Which of the following can result from a deficiency of pyruvate kinase in the erythrocyte?

Accepted Answer

A)  Gain of ATP 
B)  Erythrocyte membrane failure with loss of potassium 
C)  Sodium and calcium depletion 
D)  Overhydration 
A)  Gain of ATP 
B)  Erythrocyte membrane failure with loss of potassium 
C)  Sodium and calcium depletion 
D)  Overhydration

Exam 18: Hemolytic Anemia: Enzyme Deficiencies

What are the two main metabolic pathways that erythrocytes use to break down glucose?

Explain the principle of each of the following tests. a. Fluorescent spot test b. Dye reduction test c. Ascorbate cyanide test d. Rate reduction test

Female heterozygotes for G6PD deficiency have one population of cells that is normal and one that is G6PD deficient because:

G6PD deficiency was first recognized during the Korean War when which of the following drugs were administered to the soldiers?

Increased bilirubin in the blood of infants can lead to ________ and is seen in ________.

For proper diagnosis of G6PD deficiency, timing of the testing is critical. When should it occur?

What is the purpose of the HMP shunt, and why is it important?

Which of the following does not support the diagnosis of G6PD deficiency?

What metabolic pathway catabolizes approximately 10% of the glucose essential for maintaining adequate concentrates of reduced glutathione?

Which molecule is responsible for the neutralization of harmful peroxides?

In PK deficiency there is a loss of ________, which causes failure of the cation pumps in the RBC.

Which G6PD variant has normal activity and no hemolysis present?

Class IV G6PD enzymes include which of the following?

Intrinsic erythrocyte enzyme deficiencies lead to:

All of the following support the diagnosis of G6PD deficiency except:

What morphologic characteristics are found on a blood smear in G6PD deficiency?

Why are echinocytes seen in PK deficiency?

Which of the following is a quantitative test for G6PD?

Which of the following can result from a deficiency of pyruvate kinase in the erythrocyte?

Introduction

Cellular Homeostasis

Structure and Function of Hematopoietic Organs

Hematopoiesis

The Erythrocyte

Hemoglobin

Granulocytes and Monocytes

Lymphocytes

The Platelet

The Complete Blood Count and Peripheral Blood Smear Evaluation

Introduction to Anemia

Anemias of Disordered Iron Metabolism and Heme Synthesis

Hemoglobinopathies: Qualitative Defects

Thalassemia

Megaloblastic and Nonmegaloblastic Macrocytic Anemias

Hypoproliferative Anemias

Hemolytic Anemia: Membrane Defects

Hemolytic Anemia: Immune Anemias

Hemolytic Anemia: Nonimmune Defects

Nonmalignant Disorders of Leukocytes: Granulocytes and Monocytes

Nonmalignant Lymphocyte Disorders

Introduction to Hematopoietic Neoplasms

Myeloproliferative Neoplasms

Myelodysplastic Syndromes

Acute Myeloid Leukemias

Precursor Lymphoid Neoplasms

Mature Lymphoid Neoplasms

Hematopoietic Stem Cell Transplantation

Morphologic Analysis of Body Fluids in the Hematology

Primary Hemostasis

Secondary Hemostasis and Fibrinolysis

Disorders of Primary Hemostasis

Disorders of Secondary Hemostasis

Thrombophilia

Hemostasis: Laboratory Testing and Instrumentation

Hematology Procedures

Bone Marrow Examination

Automation in Hematology

Flow Cytometry

Chromosome Analysis of Hematopoietic and Lymphoid Disorders

Molecular Analysis of Hematologic Diseases

Quality Assessment in the Hematology Laboratory

Filters

Increased bilirubin in the blood of infants can lead to and is seen in .