Disorder of RBCs

Question 1

What is MVC?

Answer 1

This is the Mean Corpuscular Volume which measures the average size of RBC, helps with the classification of anemia (80-100)

Question 2

What are the three categories of anemia and how is it classified?

Answer 2

1. microcytic (small cell) anemia is <80
2. normocytic (normal cell) anemia is 80-100
3. macrocytic (large cell) anemia is >100

Question 3

What is pernicious anemia?

Answer 3

Reduction in the amount of RBCs caused by a vitamin B12 deficiency.

Question 4

What are the two types of macrocytic anemias?

Answer 4

Pernicious and folic acid anemia

Question 5

What are the causes of pernicious anemia?

Answer 5

Vegan diet, gastrectomy, resected ileum, infestation with tapeworms, alcohol abuse, pregnancy, hyperthyroidism, cancer, and smoking all lead to B12 deficiency.

Question 6

What are the signs of pernicious anemia?

Answer 6

Beefy red tongue, weakness/fatigue, low appetite, neurologic symptoms such as paresthesia of hands/feet and loss of sensation. Also neurological decline including encephalopathy, myelopathy, and optic neuropathy can occur.

Question 7

What is folic acid anemia?

Answer 7

Reduction of RBC production secondary to a deficiency in folic acid.

Question 8

What is the most common cause of folic acid anemia?

Answer 8

Most common cause is a deficient dietary intake. Increased amounts are needed during pregnancy and in lactating females.

Question 9

What are the signs of folic acid anemia?

Answer 9

cheilosis, stomatitis, painful ulcerations of the buccal mucosa and tongue. Dysphagia, flatulence, and water diarrhea can also occur.

Question 10

What causes macrocytic anemia?

Answer 10

Both vitamin B12 and folic acid are required for RBC synthesis. Vitamin B12 is needed to metabolize folic acid. Folic acid is needed for RB nuclear DNA and RNA maturation because it is a part of the purines. So the DNA and RNA do not mature, however, the cytoplasm of the cell continues to grow and we end up with large cells. These cells do not mature and are destroyed in the bone marrow hence causing the macrocytic anemia

Question 11

What is a microcytic anemia?

Answer 11

iron deficiency anemia

Question 12

What is iron deficiency anemia?

Answer 12

a reduction in the production of RBCs secondary to a deficiency in iron

Question 13

Who are at risk for IDA?

Answer 13

those with chronic blood loss or pregnancy, impoverished persons, infants drinking cows milk because iron bioavailability is low in cow’s milk, and teens with a poor diet

Question 14

What is the pathogenesis of iron deficiency anemia?

Answer 14

Iron is needed for the production of hemoglobin. When iron stores are depleted, there is smaller amounts of Hg produced resulting in the production of small RBCs.

Question 15

What are the signs of iron deficiency anemia?

Answer 15

SOB and hypoxia, glossitis, and spoon-shaped nails. People may experience a painful mouth. Other symptoms include angular stomatitis and hyposalivation.

Question 16

What is a normocytic anemia?

Answer 16

Anemia of chronic diseases or AOCD occurs secondary to chronic infection and is characterized by a decrease in erythropoiesis and impaired iron use

Question 17

What is the pathogenesis of anemia of chronic disease?

Answer 17

During times of chronic inflammation, the body releases a large number of cytokines. IL-6 increases the release of hepcidin which regulates the primary iron transporter ferroportin. It transports iron from macrophages to the plasma. Too much hepcidin decreases ferroportin activity and suppresses the release of iron. There is decreased erythropoiesis noted in AOCD due to the inflammatory changes.

Question 18

What is sickle cell disease?

Answer 18

Characterized by abnormal Hgb S. Hemoglobin S is formed because of a genetic mutation which results in the replacement of glutamate amino acid with a valine amino acid in the B globin hemoglobin chain. When there is a lack of oxygen the Hg S molecules come together and transform the normal shape of the RBC into a sickle shape.