Deck 11: Thalassemia

Question 1

A fusion of delta and beta globin chains produces which of the following hemoglobins?

A)Hemoglobin F
B)Hemoglobin Lepore
C)Hemoglobin Bart's
D)Hemoglobin Portland

Answer 1

Hemoglobin Lepore

Question 2

Most defects in beta thalassemia are a result of what genetic defect?

A)Loss of gene expression due ti promoter region methylation
B)Point mutations in regions of the DNA controlling gene expression
C)Deletion of the structural globin gene
D)Omission of the alpha globin chain

Answer 2

Point mutations in regions of the DNA controlling gene expression

Question 3

Impaired alpha chain production in alpha thalassemias causes:

A)Overproduction of hemoglobin F and A2.
B)Production of Hb Bart's and Hb H.
C)Normal hemoglobin distribution.
D)Fusion of alpha and gamma chains.

Answer 3

Production of Hb Bart's and Hb H.

Question 4

Why are bone changes and deformities common findings in beta thalassemias y?

A)Because of increased globin chain synthesis
B)The impaired globin chain synthesis causes erythroid hypoplasia.
C)The impaired globin chain synthesis causes increased erythropoiesis resulting in bone marrow expansion.
D)The impaired globin chain synthesis causes impaired oxygen delivery to the bone tissue, which causes bone deformities.

Question 5

Thalassemias are defined as:

A)Qualitative defects in globin chain synthesis.
B)Quantitative defects in globin chain synthesis.
C)Kinetic defects of iron in heme synthesis.
D)Structural defects in heme synthesis.

Question 6

All of the following can lead to the development of thalassemias except:

A)Deletion mutation.
B)Substitution mutation.
C)Exposure to a mutagenic agent.
D)Frameshift mutation.

Question 7

When three of the four alpha genes are deleted, the disorder is known as what?

A)α-thalassemia
B)β-thalassemia
C)Hydrops fetalis
D)Hemoglobin H disease

Question 8

Choose the thalassemia with the best prognosis from the choices below.

A)Hgb H disease
B)Silent carrier alpha thal
C)Beta thal minor
D)Beta thal intermedia

Question 9

Which of the following statements is true regarding hemoglobinopathies but false in thalassemia?

A)Abnormal hemoglobin will polymerize inside erythrocytes, altering red cell shape.
B)Novel hemoglobins composed of abnormal combinations of normal globin chains can be detected on hemoglobin electrophoresis.
C)Elevations in embryonic and fetal hemoglobins can be observed.
D)The amino acid sequence of the globin chains of the abnormal hemoglobins is normal.

Question 10

All of the following morphology are typically seen in beta thalassemia patients except:

A)Codocytes.
B)Polychromasia.
C)Microcytes.
D)Drepanocytes.

Question 11

What can explain the imbalanced synthesis of either the alpha or beta chain in thalassemia?

A)Deletions of any of the gene clusters
B)Abnormal production of gamma chains
C)Presence of abnormal hemoglobin chains
D)Continued synthesis of psilon and zeta production after birth

Question 12

Thalessemia differs from hemoglobinopathies by what characteristic?

A)The production of abnormal globin chains
B)The point of genetic mutations
C)Decreased synthesis of normal hemoglobin
D)Qualitative defect in the globin structure

Question 13

What is the treatment of choice for thalassemias?

A)Supportive transfusions
B)Bone marrow transplant
C)Chemotherapy
D)Radiation

Question 14

Impaired beta chain production translates to what on hemoglobin electrophoresis?

A)An increase in Hb H
B)An increase in Hb A1
C)An increase in Hb F and Hb A2
D)A decrease in Hb S

Question 15

Alpha thalassemia major results from deletion in _____ alleles of the alpha chain gene.

A)1
B)2
C)3
D)4

Question 16

The geographic prevalence of alpha thalassemia is greatest in people of this ancestry:

A)Mediterranean, American Indians.
B)Asian, Mediterranean, African.
C)Canadian, African, Indian.
D)South American, African, Asian.

Question 17

Laboratory findings in thalassemia often include which of the following?

A)Microcytic hyperchromic anemia
B)Microcytic hypochromic anemia
C)Macrocytic hyperchromic anemia
D)Macrocytic hypochromic anemia

Question 18

What test could provide the differential diagnosis between beta thalassemia minor and iron deficiency?

A)PB smear
B)Iron studies
C)Hemoglobin electrophoresis
D)Bone marrow aspirate

Question 19

Molecular analysis on a 4-month-old Chinese patient revealed three alpha genes deleted on chromosome 16.The physician ordered a hemoglobin electrophoresis on this patient.What would be the expected finding?

A)80% F; 15% A1; 5% A2
B)95% Hgb H
C)95% Hgb Bart's
D)80% A1; 10% F; 10% A2

Question 20

Hemoglobin H disease can be detected by which of the following laboratory methods?

A)Complete blood count
B)PB smear for Heinz bodies
C)Bone marrow aspirate
D)Brilliant cresyl blue staining for Hb H inclusions

Question 21

A promoter mutation of a globin chain gene in thalassemia has this effect on the globin chain:

A)Amino acid change.
B)Longer globin chain.
C)Shorter globin chain.
D)Reduced or absent production.

Question 22

List the predominating hemoglobins in each of the following disorders:

A)Hgb H disease
B)Alpha thal minor
C)Beta thal major
D)Beta thal intermedia

Question 23

A physician diagnoses a patient with iron-deficiency anemia, and begins treatment with iron supplementation.He scheduled a repeat appointment in six months that included routine blood work.Her blood work at this repeat appointment indicates a microcytic normochromic picture with elevated iron levels.Based on these findings, what should the doctor do next?

A)Order a bone marrow aspirate.
B)Order a hemoglobin electrophoresis.
C)Order a repeat CBC.
D)Repeat the iron studies.

Question 24

Why are thalassemias considered a separate entity from hemoglobinopathies?

Question 25

What is another name for the phenotype of α-thalassemia major?

A)Hemoglobin H disease
B)Hydrops fetalis
C)Silent carrier
D)β-thalassemia major

Question 26

The hemoglobin Constant Spring variant of alpha thalassemia is caused by:

A)A gamma chain fused to an existing beta chain.
B)A beta chain fused to an existing alpha chain.
C)An elongated alpha chain.
D)An elongated beta chain.

Question 27

Correlate the mutation type to each of the disorders below:

A)Alpha thal major
B)Beta thal major
C)Alpha thal silent carrier

Question 28

When a diagnosis of thalassemia is suspected, this test should always be done.

A)Hemoglobin electrophoresis
B)Bone marrow aspiration
C)Iron studies
D)Vitamin B₁₂ assay

Question 29

Nucleated red blood cells in the peripheral blood are a common finding in beta thalassemia patients.Explain why.

Question 30

What is the typical electrophoresis pattern in each of the disorders below?

A)Alpha thal minor
B)Hgb H disease
C)Beta thal major
D)Beta thal minor

Question 31

Which of the following disorders is characterized by an absence of beta and delta chain production and compensated for by increased gamma chain production?

A)Hemoglobin Lepore
B)Alpha thal major
C)Hydrops fetalis
D)HPFH

Question 32

What red cell morphology marks most types of thalassemia?

A)Target cells
B)Basophilic stippling
C)Polychromasia
D)Normal findings