Anemia Due to Hemolysis

Question 1

Hemolysis is defined as __________.

Answer 1

decreased RBC survival or an increase in RBC turnover beyond the normal range

Question 2

RBCs can survive in blood for _________.

Answer 2

120 days (+/- 20 days)

Question 3

Marrow production can increase by ______.

Answer 3

6-8 fold

Question 4

List five cellular processes associated with normal turnover.

Answer 4

• decreased enzyme activity
• changes in calcium balance
• oxidative injury
• changes in membrane surface constituents
• antibodies attaching to membrane surface

Question 5

What lab values are typically elevated in hemolytic anemia?

Answer 5

• reticulocyte count
• serum/urine hemoglobin
• bilirubin (unconjugated)
• methemalbumin
• LDH, SGOT (“housekeeping enzymes”)

Question 6

What is the most common molecular abnormality in hereditary spherocytosis?

Answer 6

Spectrin deficiency

Question 7

Hereditary spherocytosis presents with _______.

Answer 7

anemia, intermittent jaundice, splenomegaly, and responsiveness to splenectomy

Question 8

Other than spectrin deficiency, spherocytosis can also be caused by _________.

Answer 8

ankyrin and band 3 defects

Question 9

Familial spherocytosis is transmitted in a _________.

Answer 9

dominant (75%) and recessive (25%) manner

Question 10

Conjugated hyperbilirubinemia results from ________.

Answer 10

liver damage

Question 11

Aplastic crisis is _________.

Answer 11

the temporary cessation of RBC production (which is markedly worse in patients with sickle cell)

Question 12

Genetically, glucose-6-phosphate dehydrogenase deficiency is _______.

Answer 12

an X-linked recessive disorder

Question 13

G6PD is involved in the ______ pathway, which produces NADPH that then leads to ________.

Answer 13

pentose; glutathione production–important for production against oxidative damage

Question 14

In autoimmune hemolytic anemia, ______ causes intravascular hemolysis and _____ causes extravascular hemolysis.

Answer 14

IgM; IgG

Question 15

Splenic hemolysis is referred to as _______.

Answer 15

extravascular

Question 16

In extravascular hemolysis, macrophages ________.

Answer 16

swallow RBCs in the spleen, storing iron in ferritin and releasing protophorphyrin as bilirubin

Question 17

In the liver, bilirubin released by macrophages is _________.

Answer 17

metabolized in the phase II pathway (by addition of a glucuronic acid

Question 18

Describe what happens in the absence of glutathione (as found in G6PD deficiency).

Answer 18

Inability to protect against oxidation results in denatured hemoglobin that binds to the membrane, damaging the cell.

Question 19

Coombs tests examine for _______.

Answer 19

hemolytic anemia