Sickle Cell Anemia

Question 1

Contents of HbA, HbA2, and HbF

Answer 1

Question 2

sickle cell anemia is a qualitative or quantitative disease?

Answer 2

qualitative (there is a functional decrese)

(thalassemia in a quantitative issue where there is an overall decrease in globin

Question 3

a single nucleotide shift causes an AA Switch from __to ____, causing hemoglobin S, which is A2B___

Answer 3

switch from glu to val, causing A2B^6, (HbS)

Deoxygenation induces
conformational in Hb S.

• Hydrophobic patch at the
site of b6 valine
replacement (projection)
binds to a similar site on
another tetramer
(indentation).
• Formation of polymers.

• Assembly of deoxy-HbS into
helical 14 strand fibers.
• RBC distorted, sickle shape

Question 4

describe the HPLC findings of someone with. no SS, with heterozygous SS and homozygous SS

Answer 4

Question 5

characteristic findings on a PBS with someone with SS

Answer 5

• normochromic and normocytic (this is a qualitative disease, not quantitative, thus contents inside wouldn’t produce decrease in size)
• sickled cells
• polychromasia
• few target cells
• howell jolly bodies (denatured Hb that usually removed from the spleen)
• wbc and platelts normal or elevated

Question 7

broad clinical pathologies of SS

Answer 7

1. vaso-occlusion
2. chronic inflammatory state
3. hemolysis
4. chronci organ damage.

Question 8

vaso-occlusive complications

Answer 8

acute chest syndrome

stroke

painful episodes

splenic sequestration

priaprism

leg ulcers

Question 9

comp;lications of hemoylsis

Answer 9

1. anemia (rbcs don’t work properly. then they make their way to the spleen where they get jammed up and sequestered because the spleen gets rid of bad blood cells. The spleen expands – splenomeagly seen early on. Causes hypovolemia and anemia
2. cholelithiasis (gall stones)– bilirubin elevation because of hemolysis and trying to get rid of defunct RBCs. can cause gall stones. most gallstones are produced from excess bilirubin, which is caused by the constant breakdown of red blood cells. Biliary sludge (formed when excess bile settles in the duct) can also lead to gallstones forming in people with sickle cell disease.
3. pulmonary hypertension.

Question 10

key treatment for SS disease modifying therapy

Answer 10

1. hydroxyurea.

increases HgbF levels. national guidelines suggest consideration of HU for all scd patients.

2. chronic transfusion program with iron chelation

Question 11

key treatment for SS disease CURATIVE therapy

Answer 11

bone marrow transplant.

Question 12

end manifestations of sickle cell anemia

Answer 12

SICKLE acronym