Macrocytic Aneamia

Question 1

What defines anemia?

Answer 1

A decrease in hemoglobin concentration below the lower normal limit for age sex

Question 2

How is anemia classified?

Answer 2

By etiology
severity

Question 3

What are the main types of anemia based on morphology?

Answer 3

Microcytic normocytic macrocytic

Question 4

What is macrocytic anemia?

Answer 4

Anemia with an MCV > 100 fL where red cells are larger than normal.

Question 5

What are the two main types of macrocytic anemia?

Answer 5

Megaloblastic and non-megaloblastic.

Question 6

What characterizes megaloblastic anemia?

Answer 6

Oval macrocytes with nuclear-cytoplasmic asynchrony in bone marrow erythroblasts often due to defective DNA synthesis.

Question 7

What is the most common cause of megaloblastic anemia?

Answer 7

Deficiency of vitamin B12 and/or folate.

Question 8

What characterizes non-megaloblastic macrocytic anemia?

Answer 8

Round macrocytes without nuclear-cytoplasmic asynchrony often due to increased lipid deposition in red cell membranes.

Question 9

What is the most frequent cause of non-megaloblastic macrocytosis?

Answer 9

Alcohol consumption.

Question 10

List other causes of non-megaloblastic macrocytic anemia.

Answer 10

Reticulocytosis liver disease

Question 11

What are the primary causes of vitamin B12 deficiency?

Answer 11

Decreased intake and impaired absorption.

Question 12

List causes of impaired absorption of vitamin B12.

Answer 12

Pernicious anemia gastrectomy

Question 13

What are the primary causes of folate deficiency?

Answer 13

Increased demand decreased intake

Question 14

List conditions with increased demand for folate.

Answer 14

lactation Pregnancy

Question 15

List dietary causes of folate deficiency.

Answer 15

Old age low socioeconomic status

Question 16

List absorption-related causes of folate deficiency.

Answer 16

Drugs (e.g. anticonvulsants

Question 17

How does folate deficiency cause megaloblastic anemia?

Answer 17

It inhibits thymidylate synthesis necessary for DNA synthesis

Question 18

What is the role of vitamin B12 in folate metabolism?

Answer 18

It converts methyl-THF to THF a necessary substrate for DNA synthesis.

Question 19

What are common clinical features of macrocytic anemia?

Answer 19

Shortness of breath easy fatiguability

Question 20

List additional symptoms specific to megaloblastic anemia.

Answer 20

Red beefy tongue angular cheilosis

Question 21

What initial investigations are done for macrocytic anemia?

Answer 21

Full blood count reticulocyte count

Question 22

What are additional tests for diagnosing megaloblastic anemia?

Answer 22

Serum vitamin B12 serum and red cell folate

Question 23

What is the main treatment for megaloblastic anemia?

Answer 23

Supplementation with the appropriate vitamin (IM B12 for severe cases oral B12 for mild cases

Question 24

What caution must be taken when giving folic acid for megaloblastic anemia?

Answer 24

Ensure no underlying vitamin B12 deficiency before administering folic acid.

Question 25

What is the typical response to treatment in megaloblastic anemia?

Answer 25

Improvement within 24-48 hours with reticulocyte rise by Day 4

Question 26

What are the common causes of megaloblastic anemia?

Answer 26

Deficiency of vitamin B12 and folate.

Question 27

What is the difference between megaloblastic and non-megaloblastic macrocytic anemia?

Answer 27

Megaloblastic anemia shows nuclear-cytoplasmic asynchrony and is commonly due to B12/folate deficiency while non-megaloblastic is often due to alcohol and lacks nuclear-cytoplasmic asynchrony.