D52.0/D52.1/D52.8/D52.9/D53.1
DESCRIPTION
Anaemia with large red blood cells is commonly due to folate or vitamin B12 deficiency.
Folate deficiency is common in pregnant women and in the postpartum period, and in alcoholics. Macrocytic anaemia in these patients can be assumed to be due to folate deficiency and does not require further investigation. See: Anaemia in pregnancy.
Vitamin B₁₂ deficiency occurs mainly in middle-aged or older adults, and can cause neurological damage if not treated.
Macrocytic anaemia outside of pregnancy or the postpartum period requires further investigations to establish the cause.
INVESTIGATIONS
FBC will confirm macrocytic anaemia.
- MCV will be elevated.
- White cell count and/or platelet count may also be reduced.
If there is a poor response to folate, measure serum vitamin B12 .
Note: Zidovudine and stavudine cause elevated MCV. Zidovudine often causes anaemia and/or decreased white cell count. It is not necessary to measure folate and B12 if the patient is not anaemic.
GENERAL MEASURES
- Dietary advice: Increase intake of folic acid rich foods such as:
- Liver, eggs, fortified breakfast cereals, citrus fruit, spinach and other green vegetables, lentils, dry beans, peanuts.
- Reduce alcohol intake.
- Vitamin B₁₂ deficiency anaemia:
- High protein diet is recommended (1.5g/kg/day).
- Increase intake of dietary vitamin B₁₂ sources, including meat (especially liver), eggs and dairy products.
MEDICINE TREATMENT
- Folic acid deficiency:
- Folic acid, oral, 5 mg daily until Hb is normal.
- Check Hb monthly.
Folic acid given to patients with vitamin B₁₂ deficiency can mask vitamin B₁₂ deficiency and lead to neurological damage, unless vitamin B₁₂ is also given.
REFERRAL
- Patients with suspected B₁₂ deficiency.
- Chronic diarrhoea.
- Poor response within a month of treatment.
- Macrocytic anaemia of unknown cause.