Anemia

Question 1

What is the definition of anemia?

Answer 1

low Hgb
low Hct
low RBC

(any one of them)

Question 2

What are the general causes of anemia?

Answer 2

1. diminished production of RBC precursors
2. impaired production of mature RBCs by bone marrow
3. decreased prodution of Hgb
4. increased destruction of RBCs
5. Acute or chronic blood loss
6. Combo of the above

Question 3

What are the two most common genetic non-hemolytic anemias from decreased red cell production?

Answer 3

Diamind-Blackfan anemia

Fanconi Anemia

Question 4

What are the congenital megaloblastic anemias (impaired DNA synthesis without impairment of protein synthesis = big cells without division)?

Answer 4

Lesch-Nyhan
Homocysteinuria
Orotic aciduria
Congenital dyserythropoietic anemia

Question 5

What are the common congenital causes of decreased globin producion?

Answer 5

thalassemias and hemoglobinopathies

Question 6

What are the common congenital causes of decreased production of heme?

Answer 6

porphyrias

congenital sideroblastic anemia (lack enzyme to incorporate iron into porphyrin to make heme)

Question 7

What are the acquired bone marrow erythroid hypoplasia causes?

Answer 7

DRUGS and BUGS!

Toxins, radiation, infections (Parvo, CMV, EBV), Autoimmune (acquired, neoplasm), acquire dmutations, relative erythroid hypoplasia caused by displacement (non-myeloid neoplasms), idiosyncratic

Question 8

What are the causes of acquired ineffective bone marrow production of mature red cells?

Answer 8

megaloblastic anemia (drugs, toxins, B12 def, folate def)

myeloid neoplasms

Question 9

What is the most common cause of decreased heme production (acquired)?

Answer 9

IDA by far

bu also can have anemia of chronic disease, sideroblastic anemias - lead, ethanol,, myeloid neoplasms

Question 10

What enzyme is inhibited by lead and ethanol and heavy metals to cause sideroblastic anemia?

Answer 10

ferrochelatase (it’s an enzyme that also needs vitamin B6 and copper)

Question 11

What are the 5 GENERAL causes of hemolytic anemia?

Answer 11

damaged/defective membrane
abnormal hemoglobin
metabolic effect
immune reaction
mechanical destruction

Question 12

What is a reticulocyte?

Answer 12

an erythrocyte at the stage of developmen twhere it has not yet lost its ribosomal RNA and become a mature red cell

Question 13

What hormone will increase the number of reticulocytes?

Answer 13

erythropoietin

Question 14

How do we count the reticulocytes?

Answer 14

we use a ribosomal stain to color the RNA and count them with a machine

Question 15

Why do we need to correct a manual (percent) reticulocyte count?

Answer 15

It’s a relative reticulocyte count compared to the # of RBCs. So if someone is super anemic, they may have an elevated reticulocyte count just because it’s relative but the body might not actually be making enoguh reticulocytes for the number of RBCs.

Question 16

How do you correct a manual retic count?

Answer 16

you use the patient’s hematocrit and depending on the # you use a different correction factor

RPI = [%retic x (Patient HCT/normal HCT)]/Correction Factor

Question 17

RPI less than what suggests a failure of erythropoeisis?

Answer 17

less than 2

Question 18

RPI over what suggests marrow hyperproliferation or appropriate response?

Answer 18

over 3

Question 19

What’s going on if you have an anemia with an elevated absolute retic count?

Answer 19

bleeeding
hemolysis
patient treated with an responding to EPO

Question 20

What could be going on with an anemia with normal or low absolute retic count?

Answer 20

bone marrow erythroid hypoplasia

ineffective production of mature RBCs
decreased heoglobin production

bleeding or heolysis combined with one of the above

acute bleeding or hemolysis (too acute for erythropoietin response)

Question 21

What serum chemistries should you get for anemia workup?

Answer 21

congenital enzymatic panels
iron studies
B12
folate
hemolysis workup

(beyond that consider bone marrow biopsy)