Haematological: Macrocytic Anaemia

Question 1

what is Macrocytic anaemia?

Answer 1

a type of anaemia that causes unusually large red blood cells

NB: Usually, red blood cells are between 80–100 fL. Red blood cells larger than 100 fL are considered macrocytic.

Question 2

what are the causes of Macrocytic anaemia?

Answer 2

Deficiencies in vitamin B-12 or folate (Vitamin B-9)

Question 3

B-12 is an essential vitamin obtained from what?

Answer 3

• diet or supplementation

- animal and dairy products such as meat, poultry, milk, and eggs.

Question 4

B-9 (folate) is an essential vitamin obtained from what?

Answer 4

green vegetables, legumes, and some fruits

Question 5

what are some risk factors for Macrocytic anaemia?

Answer 5

• B-12 and/or B-9 (folate) deficiency.
• Medications; Medicines that diminish the breakdown of vitamin B12 from food source (acid blockers and proton-pump inhibitors) or decrease absorption of vitamin B12 (metformin) can also cause deficiency.
• Malabsorption syndromes; IBD, bacterial overgrowth syndromes.
• Liver disease.
• Hypothyroidism.

Question 6

which medications could cause Macrocytic anaemia?

Answer 6

Medicines that:

1. diminish the breakdown of vitamin B12 from food source (acid blockers and proton-pump inhibitors)
2. decrease absorption of vitamin B12 (metformin) can also cause deficiency.

Question 7

what investigations would you conduct to confirm a diagnosis of Macrocytic anaemia?

Answer 7

Full blood count; Result: elevated MCV, low haematocrit.

consider, serum B12, serum folate (B-9), reticulocyte count