10.09.18 Hemolysis

Question 1

A group of disorders characterized by decreased red cell lifespan

Answer 1

Hemolytic anemia

Question 2

What are the clinical features of hemolytic anemia?

Answer 2

1. Jaundice
2. Dark urine (tea/red)
3. Pigmented gallstones
4. Ankle ulcers
5. Sphenomegaly
6. Aplastic crises (assoc. with Parovirus B19)
7. Increased req. for folate

Question 3

Yellowing sclera

More generalized yellow discoloration of tissues

Answer 3

scleral icterus

Jaundice

Question 4

When are splenectomies generally done?

Answer 4

To treat disorders where there is uncontrolled splenic destruction of RBC/platelets

Question 5

small round blue DNA remnants in periphery of RBCs

Answer 5

Howell-Jolly bodies

Question 6

What kid of RBC abnormalities would you find after a splenectomy?

Answer 6

1. Target cells
2. Acanthocytes
3. Schistocytes
4. Nucleated Red Cells
5. Howell Jolly bodies

Question 7

Non-encapsulate DNA virus; destroys RBC precursors

Normal individuals have no significant effet but in those with hemolytic anemia loss of RBC production can reduce reticulocyte count

Answer 7

Parovirus B19

Question 8

Parovirus B19 can cause a loss of RBC production, reducing reticulocyte count and Hb values causing what?

Answer 8

Aplastic crisis

Question 9

How are hemolytic anemias classified?

Answer 9

1. Sites of RBC destruction
2. Acquired vs. Congenital
3. Mechanism of RBC damage

Question 10

Macrophages in spleen, liver, and marrow remove damaged or antibody-coated RBC

Answer 10

Extravascular Hemolysis

Question 11

RBC rupture within the vasculature, releasing free hemoglobin into the circulation

Answer 11

Intravascular Hemolysis

Question 12

What is the laboratory evidence for hemolysis?

Answer 12

1. Increased RBC production
   - elevated reticulocyte count in the blood
   - erythroid hyperplasia in the bone marrow
   - Deforming changes in skull/long bones
2. Increased RBC destruction
   - Elevated LDH
   - Elevated unconjugated bilirubin
   - Reduced serum haptoglobin (binds free Hb)

Question 13

Expansion of the eythroid lineage that should be myeloid: erythroid 3:1 but is now 1:10

Answer 13

Erythroid hyperplasia

Question 14

Results from increased erythropoietic activity and marrow space expansion

Answer 14

Frontal Bossing

Question 15

This type of hemolytic anemia is classified by defects in membrane skeleton proteins, defects in enzymes involved in energy production, and hemoglobin defects

Answer 15

Congenital

Question 16

The type of hemolytic anemia is classified by immune-mediated and non-immune mediated pathways

Answer 16

Acquired

Question 17

Most common defect leading to anemia

Defect in protein of membrane skeleton (ankyrin)

Causes decreased MCV

Answer 17

Heridtary Spherocytosis

Question 18

What is the genetic pattern for hereditary spherocytosis?

What will MCHC levels look like?

How do you diagnose?

How do you treat?

Answer 18

Autosomal Dominant

Elevated

Increased osmotic fragility

Folate supplementation; splenectomy

Question 19

In this disease oxidizing agents convert Hb to methemoglobin and causes it to precipitate as Heinz bodies which the spleen pinches off leaving a bite/blister cell

Answer 19

G6PD Deficiency

Question 20

How is G6PD deficiency genetically passed on?

What population is this found in?

Why does it matter if someone has G6PD deficiency?

Answer 20

X linked

Mediterreanean (more extreme) and Africans (unstable; loses activity with age)

Need to avoid oxidative drugs (quinine in malaria)

Question 21

What triggers hemolysis in G6PD deficiency?

How does G6PD levels differ after a hemolytic episode in African and Mediterranean populations?

Answer 21

Drugs/infections

Africans can have normal level since mature cells are lysed and young cells are normal; not happening in Med pop.

Question 22

What are the different types of immune hemolysis?

Answer 22

1. Warm antibody-mediated (AIHA)
2. Cold antibody-mediated
3. Drug-related hemolysis
4. Paroxysmal Nocturnal Hemoglobinuria

Question 23

Hallmark of this disease is a positive Coomb’s test

Answer 23

Autoimmune Hemolytic Anemia

Question 24

This type of anemia reacts with RBCs best at 37 degrees and don’t agglutinate RBC

IgG aginst RBC surface molecules form and coat with or without C3 complement causing engulfment by spleen and forming spherocytes

Answer 24

Warm antibody-mediated

Question 25

This type of anemia reacts best below 32 degrees and causes RBC agglutination

Pathogenic antibody is IgM

Digital ischemia

Answer 25

Cold antibody-mediated

Question 26

Tests for IgG or C3 which are bound DIRECTLY on the RBC

Answer 26

Direct Antiglobulin Test (DAT) = Direct Coomb’s test

Question 27

What are important clinical features with warm-antibody hemolytic anemia?

Answer 27

1. Positive Coomb’s test

2. Spherocytes on peripheral smear

Question 28

How do you treat AIHA?

Answer 28

Immunosuppression

• Corticosteroids
• Splenectomy or Rituximab (works against CD20 on B cells)

May require transfusion if symptomatic with anemia

Question 29

What kind of infection is associated with Cold Agglutinin Disease?

What other kind of disease is associated with it?

Can you use steroids/splenectomy?

Answer 29

Mycoplasma or Monoculeosis

Lymphoproliferative disease

No, its ineffective; use immunosuppression

Question 30

Hallmark of this disease is the presence of schistocytes on the peripheral smear and can be cause by TTP/HUS and DIC

Answer 30

Microangiopathic Hemolytic Anemia