CHAPTER 28: THALASSEMIAS Flashcards
(1) The thalassemias are caused by:
a. Structurally abnormal hemoglobins
b. Absent or defective synthesis of a polypeptide chain in hemoglobin
c. Excessive absorption of iron
d. Abnormal or defective protoporphyrin synthesis
b. Absent or defective synthesis of a polypeptide chain in hemoglobin
(2) Thalassemia is more prevalent in individuals from areas along the tropics because it confers:
a. Heat resistance to those heterozygous for a thalassemia gene
b. Selective advantage against tuberculosis
c. Selective advantage against malaria
d. Resistance to mosquito bites
c. Selective advantage against malaria
(3) The hemolytic anemia associated with the thalassemias is due to:
a. Imbalance of globin chain synthesis
b. Microcytic, hypochromic cells
c. Ineffective erythropoiesis caused by immune factors
d. Structurally abnormal hemoglobin
a. Imbalance of globin chain synthesis
(4) β-Thalassemia minor (heterozygous) usually exhibits:
a. Increased Hb Constant Spring
b. 50% Hb F
c. No Hb A
d. Increased Hb A2
d. Increased Hb A2
(5) RBC morphologic features in b-thalassemia would most likely include:
a. Microcytes, hypochromia, target cells, elliptocytes, stippled cells
b. Macrocytes, acanthocytes, target cells, stippled cells
c. Microcytes, sickle cells
d. Macrocytes, hypochromia, target cells, stippled cells
a. Microcytes, hypochromia, target cells, elliptocytes, stippled cells
(6) The predominant hemoglobin present in β0-thalassemia major is:
a. Hb A
b. Hb A2
c. Hb F
d. Hb C
c. Hb F
(7) Heterozygous HPFH is characterized by:
a. 10% to 35% Hb F with normal RBC morphology
b. 100% Hb F with slightly hypochromic, microcytic cells
c. A decreased amount of Hb F with normal RBC morphology
d. 5% to 15% Hb F with hypochromic, macrocytic cells
a. 10% to 35% Hb F with normal RBC morphology
(8) Hb H is composed of:
a. Two α and two β chains
b. Two α and two γ chains
c. Four β chains
d. Four γ chains
c. Four β chains
(9) Hb Bart is composed of:
a. Two α and two β chains
b. Two ε and two γ chains
c. Four β chains
d. Four γ chains
d. Four γ chains
(10) When one α gene is deleted (α–/αα), a patient has:
a. Normal hemoglobin levels
b. Mild anemia (hemoglobin range 9 to 11 g/dL)
c. Moderate anemia (hemoglobin range 7 to 9 gm/dL)
d. Marked anemia requiring regular transfusions
a. Normal hemoglobin levels
(11) In which part of the world is the a gene mutation causing
Hb Bart hydrops fetalis (– –/– –) most common?
a. Northern Africa
b. Mediterranean
c. Middle East
d. Southeast Asia
d. Southeast Asia
(12) The condition Hb S-β0-thalassemia has a clinical course that resembles:
a. Sickle cell trait
b. Sickle cell anemia
c. b-Thalassemia minor
d. b-Thalassemia major
b. Sickle cell anemia
(13) Hb H inclusions in a supravital stain preparation appear as:
a. A few large, blue, round bodies in the RBCs with aggregated reticulum
b. Uniformly stained blue cytoplasm in the RBC
c. Small, evenly distributed, greenish-blue granules that pit the surface of RBCs
d. Uniform round bodies that adhere to the RBC membrane
c. Small, evenly distributed, greenish-blue granules that pit the surface of RBCs
(14) Which of the following laboratory findings is inconsistent with β-thalassemia minor?
a. A slightly elevated RBC count and marked microcytosis
b. Target cells and basophilic stippling on the peripheral blood film
c. Hemoglobin level of 10 to 13 g/dL
d. Elevated MCHC and spherocytic RBCs
d. Elevated MCHC and spherocytic RBCs
(15) A 4-month-old infant of Asian heritage is seen for a well-baby check. Because of pallor, the physician suspects anemia and orders a CBC. The RBC count is 4.5 x 10^9/L, Hb concentration is 10 g/dL, and MCV is 77 fL, with microcytosis, hypochromia, poikilocytosis, and mild polychromasia noted on the peripheral blood film. These findings should lead the physician to suspect:
a. β-Thalassemia major
b. α-Thalassemia silent carrier state
c. Iron deficiency anemia
d. Homozygous α-thalassemia (– –/– –)
c. Iron deficiency anemia
