Anemia & Red Cell Disorders (Rosenthal)

Question 1

what are the two types of microcytic anemia, indicated by blood cells that are small (MCV

Answer 1

thalassemia and iron deficiency

Question 2

what are the two types of macrocytic anemia, indicated by blood cells that are small (MCV >100 fl)?

Answer 2

B12 or folate deficiency and reticulocytosis

Question 3

how long does it take for the reticulocyte count to go up following acute blood loss?

Answer 3

about 1 week

Question 4

Which of the following is NOT a lab finding in hemolytic anemia?
A. Indirect (unconjugated) bilirubin
B. increased LDH
C. increased haptoglobin
D. increased reticulocytes
E. increased polychromasia on the blood smear

Answer 4

C. Haptoglobin actually decreases, because it binds to free hemoglobin (of which there is plenty following hemolysis of red cells) and is cleared by the liver.

Question 5

Which of the following is NOT a characteristic of hereditary spherocytosis?
A. It is autosomal dominant and common in N. Europeans
B. It results from a deficiency in spectrin, ankyrin or band3
C. Decreased membrane permeabliity leads to fragmentation and formation of spherocytes, which are then removed by the spleen
D. The most common mutations are in spectrin.
E. Splenectomy is curative but only needed for those with severe hemolysis.

Answer 5

D. The most common mutation is ankyrin.

Question 6

This x-linked deficiency results from enzyme instability, which results in a lack of NADPH and therefore reduced glutathione, leaving the cell vulnerable to oxidative stress

Answer 6

G6PD deficiency; self-limited hemolysis with this deficiency occurs when oxidative stress introduced (i.e., some medications such as sulfa drugs, antimalarials, or infection or fava beans)

Question 7

these kinds of cells are the classic finding on a peripheral smear of someone with G6PD deficiency

Answer 7

blister cells (formed form the spleen plucking out the oxidized hemoglobin)

Question 8

sickle cell anemia results from this substitution at position 6 of the beta globin gene

Answer 8

valine substituted for glutamic acid (Hint: Rosenthal says this is VERY important to know!)

Question 9

apart from the distinct sickle shape of erythrocytes in sickle cell anemia, what other peripheral smear finding points to this disease?

Answer 9

the presence of howell jolly bodies. these are cells with remnants of nuclei that, with a normal functioning spleen, would be plucked out. people with sickle cell anemia have a very small infarcted spleen that often misses these and they show up in the periphery.

Question 10

patients with homozygous sickle cell disease lack what type of hemoglobin?

Answer 10

hemoglobin A. They have only HgbS.

Question 11

condition characterized by decreased alpha or beta chain production due to a hypochromic, microcytic anemia, and leading to ineffective erythropoiesis and hemolysis.

Answer 11

thalassemia

Question 12

heterozygosity in thalassemia, sickle cell anemia, and G6PD deficiency all provide protection against what disease?

Answer 12

malaria

Question 13

Which of the following statements regarding thalassemia is FALSE?
A. Beta thalassemia is most often due to splicing mutations.
B. A 4-gene Alpha chain deletion is incompatible with life
C. A 1 or 2 Alpha chain gene deletion is typically asymptomatic for anemia.
D. Beta thalassemia trait is a heterozygous condition in which decreased beta chain formation leads to excess alpha chains which precipitate and cause membrane damage
E. The major finding of beta thalassemia major on a peripheral blood smear are microcytic cells with high MCHC

Answer 13

E. The major finding on a blood smear for beta thalassemia major are microcytic cells with a low MCHC (mean corpuscular hemoglobin concentration). They are small cells (MCV

Question 14

this disease results from antibodies (usually IgG) that attack a component of the red cell membrane. when the spleen tries to remove them, the membrane is damaged, leading to a characteristic spherocytic shape

Answer 14

acquired hemolytic anemia

Question 15

what is the test for acquired hemolytic anemia and what does it measure?

Answer 15

coombs test. it determines the presence of antibody attached to the red cells.

Question 16

All of the following are morphologic findings of megaloblastic anemia EXCEPT:
A. Decreased red cell precursors
B. Large, oval-shaped macrocytic RBCs
C. Hypersegmented neutrophils
D. Hypercellular bone marrow 
E. Nuclear/cytoplasmic asynchrony

Answer 16

A. There are increased red cell precursors in the bone marrow, to ineffective erythropoeisis.

Question 17

_____ anemia arises from an autoimmune disorder in which antibodies are made against intrinsic factor in the stomach.

Answer 17

pernicious

Question 18

these types of deficit are what help distinguish folate deficiency from vitamin B12 deficiency

Answer 18

neruologic deficits (seen in B12 deficiency and NOT in folate deficiency)

Question 19

a patient who presents with normal levels of methylmalonyl CoA and succinyl CoA, but elevated levels of homocysteine is likely suffering from what kind of deficiency?

Answer 19

Folate. In addition to B12, folate is needed to convert homocysteine to methionine. If the deficiency is B12, there would be elevated levels of both homocysteine and methylmalonyl CoA, since both pathways rely on vitamin B12 and would be blocked.

Question 20

why is transferrin level (and the total binding capacity) elevated in iron deficient anemia?

Answer 20

because trasferrin is the transport protein for iron, and your body is trying to absorb as much as it can from the blood under anemic conditions.

Question 21

anemia of chronic inflammation is due to the stimulation of ____, the regulator protein of iron absorption, by inflammatory cytokines.

Answer 21

Hepcidin.

Hepcidin is a key regulator of the entry of iron into the circulation. In states in which the hepcidin level is abnormally high such as inflammation, serum iron falls due to iron trapping within macrophages and liver cells and decreased gut iron absorption.

Question 22

condition characterized by marrow failure with pancytopenia, and is mostly due to idiopathic causes but is hypothesized to be caused by an altered T cell response

Answer 22

aplastic anemia

Question 23

what is the main morphologic finding of aplastic anemia on a peripheral bone marrow smear?

Answer 23

fatty, hypocellular marrow

Question 24

anemia caused by marrow replacement (e.g., by metastatic cancer, leukemia, fibrosis, etc)

Answer 24

myelophthisic anemia

Question 25

this disease of late middle age is a myleoproliferative neoplasm that results in increased erythroid precursors and elevated hematocrit.

Answer 25

polycythemia vera. patients with this disease may present with bleeding, thrombosis, symptoms related to large spleen and pruritis (itching) after bathing. thought to arise from a mutation in the Jak2 gene.

Question 26

is EPO high or low in a patient with polycythemia vera? what is the treatment?

Answer 26

EPO would be low. This is a malignancy caused by Jak2 activation independent of EPO signaling. Treatment = phlebotomy.

Question 27

anemia of renal failure/uremia, decreased epo and erythroid precursors

Answer 27

multifactorial anemia