Anemia II Flashcards
Normochromic, Normocytic anemia with increased reticulocyte count
- prior or recent hemorrhage
- recent hemolysis
Normochromic, Normocytic anemia with normal reticulocyte count and normal bone marrow
- anemia of chronic disease
- hypothyroidism
- liver disease
What are the two causes of megaloblastic anemia
- B12 deficiency
- folate deficiency
falsely elevated MCV due to
- large number of reticulocytes (larger RBC)
- RBC clumping mimicking larger RBC
Cause of megaloblastic anemias
defective DNA synthesis results in disordered RBC maturation resulting in larger RBCs
Where does B12 come from
diet
- daily requirement is 1-2ug
How is B12 absorbed
- B12 (cobalamin) is bound to intrinsic factor in the somach
- colbalamin is released from the Cobalamin-IF complex in the ileum where it is absorbed
what cells produce intrinsic factor
gastric parietal cells
What is pernicious anemia
- autoimmune
- autoantibodies against the gastric parietal cells impair IF secretion
- deficiency of intrinsic factor which causes B12 malabsorption and megaloblastic anemia
What are some other conditions that cause B12 deficiency
- ileal disease or resection
- bacterial overgrowth
- intestinal parasites
Clinical presentation
- typical symptoms of anemia
- glossitis, jaundice, splenomegaly
- neuro findings: decreased vibratory and position sense, ataxia, paresthesias, confusion
B12 deficiency anemia
Peripheral smear
- hypersegmented neutrophils (> 5 lobes)
- anisocytosis (size)
- poikilocytosis (shape)
- macro-ovaocytes (large, oval RBC)
- could be B12 deficiency anemia or folate deficiency anemia
positive schilling test
- detects antibodies to IF
- test for pernicious anemia
elevated serum methylmalonic acid and homocysteine levels are common with which anemia
pernicious anemia
treatment of pernicious anemia
- Parenteral vitamin B12
- daily injections of 1000 ug for 1 week
- then weekly injections x 1 month
- then monthly injections for life
- ***Do not treat with folic acid alone
where does folic acid come from
- diet
- fresh, leafy vegetables
dailey requirement of folic acid normally? pregnancy?
- daily requirement 200 ug/day
- 400-800 ug/day in pregnancy
- **half life of 3 weeks
folate deficiency occurs in what conditions
- alcoholism
- end of pregnancy
- anticonvulsant therapy
Homocysteine levels and serum methylmalonic acid levels in folid acid deficiency
- Homocysteine levels elevated
- serum methylmalonic acid normal
treatment of folate deficiency
- 1 mg folic acid orally daily
- 5 mg folic acid in patients with malabsorption