Things to note:- Dietary modifications to ensure adequate intake of folate and vitamin B12.
- Identify and treat the underlying cause, e.g. antibiotics for intestinal overgrowth with bacteria.
Medical Treatment: - After blood samples for RBC, folate and vitamin B12 levels have been taken, start with folic acid and vitamin B12.
- Monitor serum potassium and replace if necessary.
- Give vitamin B12 and folic acid together until the test results are available as giving folic acid alone in patients with a B12 deficiency may precipitate a permanent neurological deficit.
Adjust management according to results.
Folic acid deficiency - Folic acid, oral, 5 mg daily until haemoglobin returns to normal.
- Prolonged treatment may be required for malabsorption states.
Vitamin B12 deficiency - Vitamin B12, IM.
- 1 mg daily for 5 days, then weekly for a further 3 doses.
- Follow with 1 mg every second month for life in patients with pernicious anaemia, except in patients with clearly modifiable nutritional deficiency.
Note: Response to treatment is associated with an increase in strength and improved sense of well-being.
Reticulocytosis begins 3-5 days after therapy and peaks at about day 7.The anaemia is corrected within 1-2 months. The white cell count and platelets normalise in 7-10 days. As there is an increase in red blood cell production, short-term iron and folic acid supplementation is also recommended.
Consider the following if there is failure to respond:
- Co-existing folate and/or iron deficiency,
- Infection,
- Hypothyroidism,
- Myelodysplasia,
- Incorrect diagnosis,and
- Drug-induced, e.g. hydroxyurea, stavudine and zidovudine.
Prophylaxis Vitamin B12 is indicated for patients after total gastrectomy or ileal resection.
- Vitamin B12, IM, 1 mg every second month for life.
Indications for folic acid:
- Chronic inherited haemolytic anaemias, e.g. sickle cell anaemia, thalassaemia.
- Myeloproliferative disorders.
- Exfoliative skin disorders.
- Increased demands, e.g. pregnancy, chronic haemodialysis.
- Folic acid, oral, 5 mg daily.