Macrocytic Anemias Flashcards
What are the 4 causes of microcytosis?
- Iron deficiency anemia
- Lead poisoning
- SS disease
- Thalassemia
What is an adverse effect of hydroxyurea (used for SS disease)?
- megaloblastic anemia (macrocytosis)
What are the 3 causes of megaloblastic anemia?
- vitamin B12 deficiency
- folic acid deficiency
- drug toxicity
What are the 6 causes of macrocytosis?
- megaloblastic anemia
- myelodysplastic syndromes
- alcoholism
- severe hypothyroidism
- acute massive blood loss
- normal variant
What are the 5 causes of normocytic anemias?
- hemolytic anemia
- inflammatory anemia
- myelophthisic anemia
- acute blood loss
- bone marrow failure syndromes
(Myelophthisic anemia is anemia characterized by the presence of immature erythrocytes in the peripheral blood due to infiltration of the bone marrow by abnormal tissue)
What peripheral blood changes are seen with megaloblastic anemias?
- hyper-segmented PMNs and macro-ovalocyte RBCs
How long does it take to develop folic acid deficiency compared to B12?
- folic acid = weeks
- B12 = years
What is the major risk of vitamin b12 deficiency?
- neurological dysfunction
How can you distinguish B12 vs Folate deficiency using methymalonic acid measures?
- will be high in B12 deficiency
- will be normal in Folate deficiency
What is the treatment for Vitamin B12 deficiency?
1 mg B12 IM daily for several days, then weekly, then monthly until repleted
What is the most common cause of drug induced macrocytic anemia?
- alcohol
What is the main etiology of myelodysplastic syndrome?
- Age
What is the major concern with myelodysplastic syndromes?
- progression to acute myeloid leukemia
Reticulocytosis occurs in what setting?
- hemolysis and acute blood loss (usually from trauma)
what are the 3 main etiologies of folate deficiency?
- inadequate dietary intake
- increased requirements (e.g. pregnancy)
- drugs that inhibit folate metabolism
