Causes of Folate Deficiency Macrocytic Anaemia

Question 1

What are the nutritional causes of folate deficiency?

Answer 1

Poor Intake

• Old age
• Poor social conditions
• Starvation
• Alcohol excess (also causes impaired utilization)

Poor intake due to anorexia

• Gastrointestinal disease (Partial gastrectomy, coeliac disease, Crohn’s disease
• Cancer

Antifolate drugs

• Phenytoin
• Methotrexate

Question 2

What are the causes of Macrocytic anaemia due to excess utilization?

Answer 2

Physiological

• Pregnancy
• Lactation
• Prematurity

Pathological

• Haematological with red cell production e.g. haemolysis
• Malignant disease with increased turnover
• Inflammatory disease
• Metabolic disease e.g. homocytinuria
• Haemodialysis or peritoneal dialysis

Malabsorption
- Occurs in small bowel disease, but the effect is minor compared to anorexia