This lady has a new macrocytic anaemia and is symptomatic. She is also mildly thrombocytopenic.
Her B12 and folate are normal, unfortunately the rest of her biochemistry has haemolysed. Her reticulocyte count is raised at 188 ×109/L. She has no B-symptoms or palpable lymphadenopathy/organomegaly.
She takes no medications, does not drink alcohol, and has a balanced diet.
Given how troubled she is by her symptoms, her GP arranges for this lady to receive a red cell
transfusion. Unfortunately her FBC sample is now a couple of days old so you are unable to obtain a
blood film. You ask the GP to repeat her FBC after a few days with a request for a blood
film. At that point, her FBC and blood film are as follows:
Hb 78 g/L
MCV 104 fL
Plt 135 x109/L
WCC 12.7 x109/L
Neut 5.8 x109/L
Lymph 5.6 x109/L
Mono 1.1 x109/L
Eosino 0.2 x109/L
Baso 0.01 x109/L
What is your main differential at this point and how would you further investigate?