Definition
Anaemia (Haemoglobin below normal range) and macrocytosis (MCV above normal range).
This guideline is also applicable to patients with macrocytosis with additional blood abnormalities (e.g. neutropenia, thrombocytopenia, monocytosis, or combinations of abnormalities).
Myelodysplasia (MDS)
The major diagnosis to be considered in patients with macrocytic anaemia which is not caused by B12/folate deficiency, thyroid disorders, or reticulocytosis, is myelodysplasia. This is a clonal marrow disorder causing peripheral blood cytopenias (sometimes increased monocytes). It generally requires a bone marrow test for confirmation of diagnosis. Treatments are available and may include blood transfusion, erythropoietin, or other therapies. Suggest however that this diagnosis is not discussed in primary care – there are many subtypes of myelodysplasia ranging from a very benign disorder requiring no treatment, to an extremely serious disorder very close to acute myeloid leukaemia. Much of the literature available on the internet concentrates on the more aggressive subtypes.
C.M & L.W 26-06-23
Who to refer:
- Macrocytic anaemia where all above investigations are normal (WGH or St Johns)
- Macrocytic anaemia where anaemia persists despite adequate replacement/treatment as indicated above (WGH or St Johns)
- Macrocytic anaemia where blood film suggests myelodysplasia (MDS) (WGH or St Johns)
- Macrocytic anaemia with increased reticulocyte count (WGH, St Johns or RIE).
- In severe cases – generally haemoglobin <80g/l or where patient is markedly symptomatic (breathless, angina, tachycardia) – refer urgently (WGH, St Johns or RIE).
How to refer:
SCI Gateway to the Department of Haematology WGH, St Johns or RIE as indicated above
Primary care investigations
- B12 and folate. Treat if deficiency is detected.
- Blood film
- Reticulocyte count.
- Thyroid function tests. Treat if abnormality is detected.
- Liver function tests
