3 HYPOCHROMIC AND MICROCYTIC ANEMIAS

Question 1

(1) The osmotic fragility test result in a patient with thalassemia major would most likely
show:

A. Increased hemolysis
B. Decreased hemolysis
C. Normal resistance to hemolysis
D. Decreased hemolysis after incubation at 37°C

Answer 1

B. Decreased hemolysis

Osmotic fragility is decreased because numerous target cells are present and have increased surface volume in patients with thalassemia major.

Question 2

(2) All of the following are characteristic findings in a patient with IDA except:

A. Microcytic, hypochromic RBC morphology
B. Decreased serum iron and ferritin levels
C. Decreased total iron-binding capacity (TIBC)
D. Increased RBC protoporphyrin

Answer 2

C. Decreased total iron-binding capacity (TIBC)

In IDA, there is an increase in TIBC and in RBC protoporphyrin. Serum iron and ferritin levels are decreased. IDA is characterized by a microcytic hypochromic anemia.

Question 3

(3) IDA may be distinguished from anemia of chronic infection by:

A. Serum iron level
B. RBC morphology
C. RBC indices
D. TIBC

Answer 3

D. TIBC

In IDA, serum iron and ferritin levels are decreased, and TIBC and RBC protoporphyrin are increased. In chronic disease, serum iron and TIBC are both decreased because the iron is trapped in reticuloendothelial (RE) cells and is unavailable to RBCs for Hgb production.

Question 4

(4) Which anemia has RBC morphology similar to that seen in IDA?

A. Sickle cell anemia
B. Thalassemia syndrome
C. Pernicious anemia
D. HS

Answer 4

B. Thalassemia syndrome

Thalassemia and IDA are both classified as microcytic, hypochromic anemias. IDA is caused by defective heme synthesis, whereas thalassemia is caused by decreased globin chain synthesis.

Question 5

(5) IDA is characterized by:

A. Decreased plasma iron, decreased % saturation, increased TIBC
B. Decreased plasma iron, decreased plasma ferritin, normal RBC porphyrin
C. Decreased plasma iron, decreased % saturation, decreased TIBC
D. Decreased plasma iron, increased % saturation, decreased TIBC

Answer 5

A. Decreased plasma iron, decreased % saturation, increased TIBC

IDA is characterized by decreased plasma iron, increased TIBC, decreased % saturation, and microcytic, hypochromic anemia. Iron deficiency occurs in three phases: iron depletion, iron deficient erythropoiesis, and IDA.

Question 6

(6) Storage iron is usually best determined by:

A. Serum transferrin levels
B. Hgb values
C. Myoglobin values
D. Serum ferritin levels

Answer 6

D. Serum ferritin levels

Ferritin enters serum from all ferritin-producing tissues and, therefore, is considered a good indicator of body storage iron. Because iron stores must be depleted before anemia develops, low serum ferritin levels precede the fall in serum iron associated with IDA.

Question 7

(7) All of the following are associated with sideroblastic anemia except:

A. Increased serum iron
B. Ringed sideroblasts
C. Hypochromic anemia
D. Decreased serum ferritin

Answer 7

D. Decreased serum ferritin

Sideroblastic anemias are a group of disorders characterized by hypochromic anemia, ineffective erythropoiesis, an increase in serum and tissue iron, and the presence of ringed sideroblasts in bone marrow.

Question 8

(8) What is the basic hematological defect seen in patients with thalassemia major?

A. DNA synthetic defect
B. Hgb structure
C. β-chain synthesis
D. Hgb phosphorylation

Answer 8

C. β-chain synthesis

In thalassemia major, there is little or no production of the β-chain, resulting in severely depressed or no synthesis of Hgb A. Severe anemia is seen, along with skeletal abnormalities and marked splenomegaly. The patient is usually supported with transfusion therapy.

Question 9

(9) Which of the following is the primary Hgb in patients with thalassemia major?

A. Hgb D
B. Hgb A
C. Hgb C
D. Hgb F

Answer 9

D. Hgb F

Patients with thalassemia major are unable to synthesize the β-chain; hence, little or no Hgb A is produced. However, γ-chains continue to be synthesized and lead to variable elevations of Hgb F in these patients.

Question 10

(10) A patient has an Hct of 30%, an Hgb of 8 g/dL, and a RBC count of 4.0 × 10^12/L. What is the morphological classification of this anemia?

A. Normocytic, normochromic
B. Macrocytic, hypochromic
C. Microcytic, hypochromic
D. Normocytic, hyperchromic

Answer 10

C. Microcytic, hypochromic

The indices will provide a morphological classification of this anemia. MCV is 75 fL (reference range 80–100 fL), MCH is 20 pg (reference range 27–31 pg), and MCHC is 26.6% (reference range 32%–36%). Therefore, the anemia is microcytic hypochromic.

Question 11

(11) In which of the following conditions is Hgb A2 elevated?

A. Hgb H
B. Hgb SC disease
C. β-thalassemia minor
D. Hgb S trait

Answer 11

C. β-thalassemia minor

Hgb A2 is part of the normal complement of adult Hgb. This Hgb is elevated in βthalassemia minor because the individual with this condition has only one normal βgene; consequently, there is a slight elevation of Hgb A2 and Hgb F.

Question 12

(12) Which of the following parameters may be similar for the anemia of inflammation and IDA?

A. Normocytic indices
B. Decreased serum iron concentration
C. Ringed sideroblasts
D. Pappenheimer bodies

Answer 12

B. Decreased serum iron concentration

Thirty to fifty percent of the individuals with anemia of chronic inflammation demonstrate a microcytic hypochromic blood picture, with decrease in serum iron. Serum iron is decreased because it is unable to escape from the RE cells to be delivered to the NRBCs in bone marrow.