What caused the macrocytosis?
Not iron deficiency. If that had been the case, the MCV would have dropped below the previous reading of 72 µm3 rather
than increasing. Hence, restarting ferrous sulfate supplementation was-once again-inappropriate. Folate deficiency was a possible cause, as was alcohol, but the latter had been excluded, at least by history.
Hypothyroidism is a recognized complication of pernicious anemia. The condition develops in 5% to 10% of patients with pernicious anemia; hyperthyroidism develops in a smaller percentage. This is another example of why it is important to diagnose the underlying cause of vitamin B12 deficiency. I evaluate thyroid function annually in all patients with pernicious anemia.
Comments
There is pancytopenia and the indices of RBC are macrocytic so in this setting the first Q is megaloplastic or non megaloplastic? and the answer is easy by see hypersegmented neutrophil in peripheral blood film or bone marrow second Q is if megaloplastic what is the cause folate or B12 deficiency and what is the cause of that? if non megaloplastic we have to rule out autoimmune hemolytic anemia, mylodysplastic syndromes, hypothyroidism.
She has gradual onset of anemic symptoms Her CBC shows macrocytic [MCV.95fl],increased RDW .Platelets counts m/b reduced(<100,000/mm3).No h/o recent bleeding exclude IDA.Jaundice exclude haemolytic .Medication with methotrexate, exclude folic acid B12 deficiency.Alcoholism exclude folic acid def.Hospitalization exclude b12 def in gastric operation.Normal BUN exclude anemia of chronic disease. Dx is probably megaloblastic anemia due to combined f/a and B12 deficiency with underlying hypovitaminosis,antimetabolytes, copper deficiency with zinc excess.Bone marrow will show megaloblasts and hypersegmented neutrophils.
Diagnosis is must before blood transfusion in this case
megaloblastic anemia
mostly pernious anaemia