Question 1

Which of the following can distinguish immune hemolytic anemia from hereditary spherocytosis in a patient with spherocytes?

Accepted Answer

A) osmotic fragility 
B) reticulocyte count 
C) presence of polychromasia 
D) direct antiglobulin test 
A) osmotic fragility 
B) reticulocyte count 
C) presence of polychromasia 
D) direct antiglobulin test

Question 2

Why is G6PD important for normal red cell survival?

Accepted Answer

A) Hemoglobin oxygen affinity is increased in its absence. 
B) It is required to regenerate reduced glutathione. 
C) It is required for insertion of iron into the protoporphyrin ring to form heme. 
D) a Chains are produced in excess in its absence. 
A) Hemoglobin oxygen affinity is increased in its absence. 
B) It is required to regenerate reduced glutathione. 
C) It is required for insertion of iron into the protoporphyrin ring to form heme. 
D) a Chains are produced in excess in its absence.

Question 3

What ethnic group most often has glucose-6-phosphate dehydrogenase (G6PD)A⁻ in the United States?

Accepted Answer

A) Northern European male subjects 
B) Asian American female subjects 
C) African American female subjects 
D) African American male subjects 
A) Northern European male subjects 
B) Asian American female subjects 
C) African American female subjects 
D) African American male subjects

Question 4

What is the typical clinical course for those with G6PD A⁻?

Accepted Answer

A) severe anemia from infancy onward 
B) moderate anemia throughout adulthood 
C) no anemia until exposure to an oxidant drug causes acute hemolysis 
D) benign because it does not cause anemia 
A) severe anemia from infancy onward 
B) moderate anemia throughout adulthood 
C) no anemia until exposure to an oxidant drug causes acute hemolysis 
D) benign because it does not cause anemia

Question 5

What red cell morphology,using Wright stain,is seen in patients with G6PD deficiency during a hemolytic episode?

Accepted Answer

A) bite cells and polychromasia 
B) Heinz bodies 
C) acanthocytes and crenated cells 
D) red cells are normal 
A) bite cells and polychromasia 
B) Heinz bodies 
C) acanthocytes and crenated cells 
D) red cells are normal

Question 6

A patient with a small number of spherocytes,increased reticulocytes,and increased MCHC has a normal osmotic fragility.Select the best course of action.

Accepted Answer

A) Dismiss the spherocytes as an artifact. 
B) Repeat the osmotic fragility after incubating the blood at 37° C for 24 hours. 
C) Check the cell counter for errors in the MCHC. 
D) Collect a new blood sample. 
A) Dismiss the spherocytes as an artifact. 
B) Repeat the osmotic fragility after incubating the blood at 37° C for 24 hours. 
C) Check the cell counter for errors in the MCHC. 
D) Collect a new blood sample.

Question 7

A patient in the hospital for a hemolytic crisis after an infection has Heinz bodies when his blood is incubated with crystal violet.The fluorescent enzyme-screening test for G6PD is normal.Select the best course of action.

Accepted Answer

A) Repeat the red cell examination with new methylene blue stain. 
B) Repeat the enzyme test several weeks after the hemolytic crisis. 
C) Perform an osmotic fragility test. 
D) Perform a haptoglobin test. 
A) Repeat the red cell examination with new methylene blue stain. 
B) Repeat the enzyme test several weeks after the hemolytic crisis. 
C) Perform an osmotic fragility test. 
D) Perform a haptoglobin test.

Question 8

Which of the following is a true statement regarding G6PD?

Accepted Answer

A) The gene is located on chromosome 22. 
B) The gene has the greatest degree of variability in the human genome. 
C) The deficiency is primarily expressed as a clinical disease in heterozygous female subjects. 
D) The normal enzyme is called G6PD A. 
A) The gene is located on chromosome 22. 
B) The gene has the greatest degree of variability in the human genome. 
C) The deficiency is primarily expressed as a clinical disease in heterozygous female subjects. 
D) The normal enzyme is called G6PD A.

Exam 24: Intrinsic Defects Leading to Increased Erythrocyte Destruction

Which of the following can distinguish immune hemolytic anemia from hereditary spherocytosis in a patient with spherocytes?

Why is G6PD important for normal red cell survival?

What ethnic group most often has glucose-6-phosphate dehydrogenase (G6PD)A⁻ in the United States?

What is the typical clinical course for those with G6PD A⁻?

What red cell morphology,using Wright stain,is seen in patients with G6PD deficiency during a hemolytic episode?

A patient with a small number of spherocytes,increased reticulocytes,and increased MCHC has a normal osmotic fragility.Select the best course of action.

A patient in the hospital for a hemolytic crisis after an infection has Heinz bodies when his blood is incubated with crystal violet.The fluorescent enzyme-screening test for G6PD is normal.Select the best course of action.

Which of the following is a true statement regarding G6PD?

An Overview of Clinical Laboratory Hematology

Safety in the Hematology Laboratory

Blood Specimen Collection

Care and Use of the Microscope

Quality Assurance in Hematology and Hemostasis Testing

Cellular Structure and Function

Hematopoiesis

Erythrocyte Production and Destruction

Erythrocyte Metabolism and Membrane Structure and Function

Hemoglobin Metabolism

Iron Kinetics and Laboratory Assessment

Leukocyte Development, Kinetics, and Functions

Platelet Production, Structure, and Function

Manual, Semiautomated and Point-of-Care Testing in Hematology

Automated Blood Cell Analysis

Examination of the Peripheral Blood Film and Correlation with the Complete Blood Count

Bone Marrow Examination

Body Fluid Analysis in the Hematology Laboratory

Anemias: Red Blood Cell Morphology and Approach to Diagnosis

Disorders of Iron Kinetics and Heme Metabolism

Anemias Caused by Defects of DNA Metabolism

Bone Marrow Failure

Introduction to Increased Destruction of Erythrocytes

Extrinsic Defects Leading to Increased Erythrocyte Destruction Nonimmune Causes

Extrinsic Defects Leading to Increased Erythrocyte Destruction Immune Causes

Hemoglobinopathies (Structural Defects in Hemoglobin)

Thalassemias

Nonmalignant Leukocyte Disorders

Cytogenetics

Molecular Diagnostics in Hematopathology

Flow Cytometric Analysis in Hematologic Disorders

Myeloproliferative Neoplasms

Myelodysplastic Syndromes

Acute Leukemias

Mature Lymphoid Neoplasms

Normal Hemostasis and Coagulation

Hemorrhagic Disorders and Laboratory Assessment

Thrombotic Disorders and Laboratory Assessment

Thrombocytopenia and Thrombocytosis

Qualitative Disorders of Platelets and Vasculature

Laboratory Evaluation of Hemostasis

Antithrombotic Therapies and their Laboratory Assessment

Hemostasis and Coagulation Instrumentation

Pediatric and Geriatric Hematology and Hemostasis

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