Macrocytic Anaemia Flashcards
What is megaloblastic anaemia?
Anaemia that is the result of impaired DNA synthesis preventing the cell from dividing normally, so keeps growing into a larger, abnormal cell - MCV > 100
Causes:
- B12 deficiency and folate deficiency
Cause of B12 deficiency?
Nutrition - vegan, poor diet, pregnancy
Malabsorption - surgery, pernicious anaemia (IF and gastric parietal cell antibodies)
Intestine cause - ileal resection (ileum is removed, B12 is normally absorbed here), tapeworm
Signs and Symptoms of B12 Def.
- Mild jaundice
- Glossitis (inflammation of tongue)
- Pale conjunctiva, nails and lips
- Angular stomatitis (inflammation of corners of lips)
- Peripheral neuropathy (may have some ‘pins & needles’)
- SADC (sub-acute degeneration of the cord): due to giving folic acid in B12 deficiency
Treatment of B12 Deficiency?
If B12 deficiency is due to lack of absorption give IM hydroxocobalamin every 3 months
- (treat B12 def. BEFORE folate def. due to risk of SADC)
Folate deficiency causes?
Nutritional - poor diet, chronic alcohol intake, (consuming goat’s milk only)
Intestinal - coeliac disease, jejunal resection (this is normally where folate is absorbed)
Excessive requirement - pregnancy, prematurity
Diseases - chronic haemolysis, severe skin disease
Drugs - alcohol, anticonvulsants, nitrofurantoin, sulfasalazine, methotrexate, trimethoprim
Treatment of folate deficiency?
- 5mg folic acid daily for 4 months
- Providing dietary advice — good sources of folate are broccoli, Brussels sprouts, asparagus, peas, chickpeas, and brown rice
Investigations for B12 deficiency?
If vitamin B12 deficiency is found, serum anti-intrinsic factor antibodies should be checked
Causes of normoblastic macrocytic anaemia?
- ALCOHOL
- Raised reticulocyte count (due to haemolytic anaemia or blood loss)
- Hypothyroidism
- Liver disease
- Drugs
- Aplastic anaemia (rare disease in which there is a deficiency of all 3 blood cells types)
