12. Hemolytic Anemias: Intracorpuscular Defects: IV. Thalassemia

Question 1

1. What is the hemoglobin defect found in thalassemia syn-dromes?
   a.Abnormal incorporation of iron molecule
   b. Defective production of the globin portion
   c. Excessive production of porphyrins
   d. Amino acid substitution

Answer 1

b. Defective production of the globin portion

Question 2

2. What type of globin chains and hemoglobin are charac-teristics of severe α thalassemia?
   a. Two α chains and two β chains (HbA)
   b. Two α chains and two δ chains (HbA2)
   c. Four β chains (HbH) or four y chains (Hb Bart’s)
   d.Two α chains and two y chains (HbF)

Answer 2

c. Four β chains (HbH) or four y chains (Hb Bart’s)

Question 3

3.Which type of thalassemia has primarily hemoglobin Bart’s and shows the following clinical expressions:infants die in utero or soon after birth,severe anemia,marked hepatomegaly and splenomegaly,and ascites?
a. Homozygous α° thalassemia(–/–)
b. Homozygous β° thalassemia(β°/β°)
c. β Thalassemia minor (β+/β)
d.Hemoglobin H disease(-α/–)

Answer 3

a. Homozygous α° thalassemia(–/–)

Question 4

4. What is the term for the clinical course of homozygous (δβ)° thalassemia?
   a. Thalassemia minor
   b. Thalassemia major
   c. Thalassemia trait
   d. Thalassemia intermedia

Answer 4

d. Thalassemia intermedia

Question 5

5. Hereditary persistence of fetal hemoglobin (HPFH) is characterized by the persistence of fetal hemoglobin into adult life. What are the clinical manifestations of this condition?

a. Chronic anemia with skeletal abnormalities caused by excessive erythropoiesis
b.Asymptomatic except during pregnancy or stressful situations
c.Hydrops fetalis syndrome
d. No significant abnormalities for heterozygous;minor symptoms for homozygous

Answer 5

d. No significant abnormalities for heterozygous;minor symptoms for homozygous

Question 6

6.What is the clinical manifestation of a thalassemia with sickle cell anemia?
a. Severe, life-threatening anemia
b. Relatively asymptomatic until placed in an oxygen-deprived environment
c. Less severe than sickle cell anemia alone
d. Skeletal abnormality, but milder anemia than sickle cell anemia

Answer 6

c. Less severe than sickle cell anemia alone

Question 7

7.What is the primary risk to thalassemia major patients who are on a high-transfusion (hypertransfusion)program?
a.Hyperviscosity of blood
b.Iron overload
c.Citrate toxicity
d. Electrolyte imbalance

Answer 7

b.Iron overload

Question 8

8.What routine hematologic finding is indicative of tha-lassemia?
a. Microcytic, hypochromic anemia
b.Macrocytic, hypochromic anemia
c. Normocytic, normochromic anemia
d.Macrocytic, normochromic anemia

Answer 8

a. Microcytic, hypochromic anemia

Question 9

9.How can iron deficiency be distinguished from heterozy-gous α or β thalassemia?
a.Heterozygous thalassemia: decreased RDW, with increased MCH and MCV and Hgb in the 10 to 14 g/dL (100-140 g/L) range; iron deficiency: increased RDW,MCH,and MCV
b. Heterozygous thalassemia: normal RDW, with decreased MCH and MCV and Hgb in the 9 to 11 g/dL (90-110 g/L) range; iron deficiency: increased RDW, with decreased MCV and MCH only in severe anemia
c.Heterozygous thalassemia:increased RDW,with decreased MCH and MCV and Hgb in the 5 to 9 g/dL ( 50- 90 g/L) range; iron deficiency: normal RDW, with normal MCV and MCH
d. Heterozygous thalassemia: normal RDW, MCH, and MCV; iron deficiency: RDW,MCH,and MCV all increased

Answer 9

b. Heterozygous thalassemia: normal RDW, with decreased MCH and MCV and Hgb in the 9 to 11 g/dL(90- 110g/L) range; iron deficiency: increased RDW, with decreased MCV and MCH only in severe anemia

Question 10

10. Which of the following cells are not found in a patient with homozygous β thalassemia?
    a.Target cells
    b.Ovalocytes
    c.Sickle cells
    d.Nucleated red cells

Answer 10

c.Sickle cells

Question 11

11. Which test is useful in demonstrating the distribution of hemoglobin F and in differentiating pancellular HPFH,heterocellular HPFH, and heterozygous δβ thalassemia?

a. Osmotic fragility
b.Kleihauer-Betke acid elution test
c.Serum ferritin level
d.Complete blood count

Answer 11

b.Kleihauer-Betke acid elution test

Question 12

12.Which of the following findings would be indicative of heterozygous β thalassemia?
a. Hemoglobin A2 level of 3.5% to 7%
b.Hemoglobin F level less than 2%
c. Hemoglobin A level of 65% to 85%
d. Hemoglobin A2 level less than 3.5%

Answer 12

a. Hemoglobin A2 level of 3.5% to 7%