Macrocytic Anemia Flashcards
1
Q
Diagnosis of b12/folate deficiency if b12 level is borderline low, 200-300
A
- measure MMA levels and homocysteine
- elevated MMA and homocysteine confirm b12 def
- elevated homocysteine and normal MMA confirms folate def
2
Q
Macrocytic anemia caused by nonmegaloblastic disorders
A
- liver disease: large target cells(MCV 105-110) and echinocytes(spur cells with multiple undulating spiny erythrocyte membrane projections)
- diminished splenic function: yields large target cells, acanthocytes(erythrocytes with only a few rather than many spiny membrane projections), Howell jolly bodies, variable numbers of nucleated erythrocytes
- reticulocytosis: increases MCV
3
Q
Treatment of b12 def
A
- oral vit b12, 1-2g/d
- injectable is necessary in malabsorption syndrome
4
Q
3 major causes
A
- folate and/or cobalamin def
- drugs affecting folate metabolism and/or DNA synthesis(etoh, zidovudine, MTX)
- acquired causes such as myelodysplastic syndrome
