Deck 15: Megaloblastic and Nonmegaloblastic Macrocytic Anemias

Question 1

It is much easier to become folate-deficient than B₁₂-deficient because:

A) The body utilizes folate more quickly than it does vitamin B₁₂
B) The body has larger vitamin B₁₂ stores than folate stores
C) The body has a greater need for folate than for vitamin B₁₂
D) It has not been determined why the body needs folate more than vitamin B₁₂

Answer 1

The body has larger vitamin B₁₂ stores than folate stores

Question 2

All of the following disorders can lead to macrocytic anemia except:

A) Alcoholism
B) Liver disease
C) Hypothyroidism
D) Iron deficiency

Answer 2

Iron deficiency

Question 3

Which clinical manifestation is common in vitamin B₁₂ deficiency but not in folate deficiency?

A) Glossitis
B) Pallor
C) Fatigue
D) Peripheral neuropathy

Answer 3

Peripheral neuropathy

Question 4

The reason that lack of vitamin B₁₂ causes megaloblastic changes is that vitamin B₁₂:

A) Is needed for the formation of nucleotide bases
B) Is needed for the conversion of methionine to SAM
C) Initiates mitosis
D) Is needed for synthesis of intrinsic factor

Question 5

Megaloblastic anemia is characterized by:

A) Hypersegmentation of PMNs
B) Presence of Heinz bodies
C) hypochromia
D) Microcytosis

Question 6

Deficiencies in folic acid lead to which of the following?

A) Nuclear cytoplasmic asynchrony
B) Absence of nuclear division
C) Excessive proliferation of myeloid precursors
D) Decreased proliferation of erythroid precursors

Question 7

Macrocytes are often seen in hospitalized alcoholics because of:

A) Alcohol toxicity on erythroid precursors
B) Stimulated erythropoiesis
C) Reticulocytosis
D) Iron deficiency

Question 8

An analyzed blood specimen reveals the following: the MCV is increased, the hemoglobin level is decreased, and the reticulocyte count is normal or low. What test could give more information on the cause of the anemia without drawing another blood specimen?

A) Serum iron
B) Vitamin B₁₂ assay
C) Blood smear morphological exam
D) Serum alcohol

Question 9

Pernicious anemia is a malabsorption of vitamin B₁₂ from what component deficiency?

A) Gastric juice
B) Intrinsic factor
C) Histamine
D) Folate

Question 10

Which test is a better indicator of folate status in the body over the past month?

A) Folate level
B) RBC folate level
C) Vitamin B₁₂ level
D) MMA

Question 11

Which of the following is found in megaloblastic macrocytosis but not in nonmegaloblastic macrocytosis?

A) Decreased WBC count and vitamin B₁₂ levels
B) Decreased hemoglobin and hematocrit
C) Normal-to-decreased reticulocyte count
D) Increased serum bilirubin

Question 12

Predict the levels of MMA and homocysteine in patients with Vitamin B₁₂ deficiency.

A) Both will be normal.
B) Both will be decreased.
C) Both will be increased.
D) MMA will be increased and homocysteine will be normal.

Question 13

Pernicious anemia is a disorder characterized by:

A) Antivitamin B₁₂ antibodies
B) Lack of IF
C) Improper dietary intake of vitamin B₁₂
D) Increased absorption of vitamin B₁₂

Question 14

Patients with ileitis can have vitamin B₁₂ deficiency complications resulting from:

A) Inadequate diet
B) Increased minimum daily requirements
C) Malabsorption
D) Biologic competition

Question 15

Megaloblastic anemia is most often caused by deficiencies of what two components?

A) Iron and transferrin
B) Ferritin and hemoglobin
C) Vitamin B₁₂ and folate
D) Iron and liver disease

Question 16

Vitamin B₁₂ is a cofactor used in the conversion of ________ to ________.

A) Hydroxocobalamin; thymidine
B) 5-methyltetrahydrofolate; tetrahydrofolate
C) Folate; methionine
D) Succinyl CoA; methylmalonic acid

Question 17

What is (are) the most appropriate reflex test(s)?

A) Iron studies
B) Bilirubin
C) Vitamin B₁₂ and folate levels
D) Hemoglobin electrophoresis

Question 18

Neurological symptoms are prevalent in Vitamin B₁₂ deficiency because of:

A) Antibodies to intrinsic factor
B) Decreased secretion of intrinsic factor
C) Improper fatty acid metabolism
D) Improper metabolism of methionine

Question 19

What would be the results of vitamin B₁₂ and/or folate levels in a diagnosis of pernicious anemia?

A) Increased folate
B) Increased vitamin B₁₂
C) Decreased vitamin B₁₂
D) Decreased folate and vitamin B₁₂

Question 20

The nuclear cytoplasmic asynchronous morphology in megaloblastosis is best characterized by:

A) Nuclear immaturity with cytoplasmic maturity
B) Nuclear maturity with cytoplasmic immaturity
C) Nuclear maturity with abundant cytoplasm
D) Normal nuclear and cytoplasmic maturity

Question 21

Autoantibodies against parietal cells and intrinsic factor are associated with:

A) Grave's disease
B) Hashimoto's thyroiditis
C) Addison's disease
D) Pernicious anemia

Question 22

All of the following are expected laboratory findings of PA except:

A) Decreased vitamin B₁₂ levels
B) Increased MMA in the urine
C) IF blocking antibodies positive
D) Decreased Gastrin levels

Question 23

What conditions listed can result in macrocytic anemia without megaloblastosis?

A) Diabetes
B) Liver disease
C) Myelodysplastic syndrome
D) Pernicious anemia

Question 24

The majority of PA patients have antibodies against what component necessary for vitamin B₁₂ absorption?

A) Parietal cells
B) Vitamin B₁₂
C) Intrinsic factor
D) Blocking antibody

Question 25

Explain why patients undergoing gastric bypass surgery are prone to developing pernicious anemia.

Question 26

Which of the following are key features found in nonmegaloblastic macrocytosis?

A) Oval red blood cells
B) Hypersegmented neutrophils
C) Jaundice, glossitis, and neuropathy
D) Round macrocytes

Question 27

Explain how high alcohol intake can cause macrocytosis.

Question 28

The defect in DNA synthesis associated with megaloblastic anemia affects which cells?

A) Only erythrocytes
B) Only gastric cells and WBCs
C) Only neurological cells
D) All dividing cells

Question 29

Which of the following is found in megaloblastic anemia but not in nonmegaloblastic macrocytic anemia?

A) Macrocytic erythrocytes
B) Howell-Jolly bodies
C) Heinz bodies
D) Hypochromia

Question 30

Explain how vitamin B₁₂ deficiency can cause folate deficiency.

Question 31

What can falsely elevate the serum folate level?

A) Hemolysis of the serum sample
B) Recent low dietary intake
C) Vitamin B₁₂ deficiency
D) Recent alcohol consumption

Question 32

Name four causes of folate deficiency. How would they differ in results in regard to serum and RBC folate levels?

Question 33

Explain why peripheral neuropathy is a common finding in vitamin B12 deficiency is.