Macrocytic Amenias

Question 1

What are the 2 most common macrocytic anemias?

Answer 1

B-12 deficiency

Folate deficiency

(They often go together)

Question 2

What are the risk factors for B12 deficiency and folate deficiency?

Answer 2

• Age: older adults
• Alcoholism
• Malnourishment
• Bariatric/gastric surgery
• Vegetarians/strict vegans (high gastric pH leads to reduced B12/folate absorption)

Question 3

List common causes of B12 deficiency.

Answer 3

• Pernicious anemia
• Inadequate dietary intake
• Gastrectomy/bariatric surgery
• Meds:
  
  • PPIs
  • Metformin
  • Colchicine
• Impaired metabolism
• H. Pylori

Question 4

List common causes of folate deficiency.

Answer 4

• Inadequate dietary intake
• Increased requirements (eg. pregnancy)
• Intestinal malabsorption

Question 5

What are the roles/functions of B12 and folate?

Answer 5

B12:
- Nerve health
- Help RBCs mature

Folate:
- Help RBCs mature

Question 6

What are the signs and symptoms of B12/folate deficiency?

Answer 6

• **Usually asymptomatic
• Unexplained neuro symptoms
• Cognitive changes
• **Burning tongue!!!

Question 7

What is the recommended treatment for asymptomatic B12/folate deficiency?

Answer 7

Oral treatment with:

• B12: 1000 - 2000 mcg daily
• Folate: 1 mg daily

Question 8

What is the recommended treatment for symptomatic B12/folate deficiency?

Answer 8

Consider IV treatment for both:

• B12: lifetime treatment if the cause is not reversible (i.e., pernicious anemia)
• Folate: 1 - 4 months or until hematologic recovery

Question 9

What is the usual expected course of B12/folate deficiency?

Answer 9

• Neurological defects of B12 deficiency are usually reversible
• With treatment, symptoms usually improve in 5- 10 days
• Reticulocyte count:
  • rapidly increases
  • peaks 7 - 10 days after treatment started