haematology: hemolytic anemia

Question 1

What is the two main categories to acquire hemolytic anemia

Answer 1

1. Inherited hemolytic anemia
2. Acquired hemolytic anemia

Question 2

What is the three categories under inherited hemolytic anemia with examples

Answer 2

1. Red cell membrane defects (hereditary spherocytosis)
2. Red cell enzyme defects (G6PD deficiency)
3. Hemoglobinopathy (sickle cell anemia & thalassemia)

Question 3

What is the two categories under acquired hemolytic anemia

Answer 3

1. Immune mediated
2. Non-immune mediated

Question 4

What is two examples of immune mediated acquired hemolytic anemia

Answer 4

1. Autoimmune hemolytic anemia
2. Alloimmune

Question 5

What is two examples of non-immune mediated acquired hemolytic anemia

Answer 5

1. Microangiopathic hemolytic anemia
2. Infections

Question 6

What is autoimmune hemolytic anemia

Answer 6

Reduced red cell mass & lifespan caused by immune-mediated destruction/lysis of RBC

Question 7

What is four causes of autoimmune hemolytic anemia

Answer 7

1. Mechanical
2. Infections
3. Venoms
4. Copper - & zinc toxicity

Question 8

What does autoimmune hemolytic anemia cause

Answer 8

Increased RBC breakdown leading to increased EPO releasing & 10x RBC production & release of reticulocytes

Question 9

What is the two main classifications of autoimmune hemolytic anemia

Answer 9

1. Intra- & extravascular hemolysis
2. Cold & warm AIHA

Question 10

Where does intravascular AIHA occur

Answer 10

RBC lyse within circulation mediated by complement & release hemoglobin that is toxic

Question 11

Where does extravascular AIHA occur

Answer 11

RBC phagocytes by macrophages in the spleen due to opsonisation by IgG & hemoglobin gets recycled

Question 12

What is three symptoms of intravascular AIHA

Answer 12

Hemoglobinaemia
Hemoglobinuria
Hemosiderinurea

Question 13

What is three symptoms of extravascular AIHA

Answer 13

Jaundice
Splenomegaly
Gallstones

Question 14

What antibodies are present in cold AIHA

Answer 14

IgM that reacts to I antigen causing cold agglutinin disease
IgG/Donath-Landsteiner Ab that reacts to P antigen causing paroxysmal cold hemoglobinuria

Question 15

What antibody is present in warm AIHA

Answer 15

IgG

Question 16

What is the outcomes of warm AIHA dependent on

Answer 16

Splenic macrophages action that is responsible to remove RBC from circulation but sometime only remove IgG antibody prolonging disease

Question 17

What is I antigen an example of

Answer 17

Molecular mimicry

Question 18

What diseases are associated with I antigen

Answer 18

Epstein Barr Virus
B cell complications
Autoimmune disease like SLE

Question 19

What is problematic with Donath-Landsteiner Ab

Answer 19

Ab-Ag complex does not dissociate at higher temperatures leading to intravascular hemolysis

Question 20

What is a typical sign of cold agglutinin disease

Answer 20

Cold changes on extremities like acrocyanosis, Raynaud’s phenomenon, livido reticularis & cutaneous necrosis/ulcer

Question 21

What is typical signs of paroxysmal cold hemoglobinuria

Answer 21

Dark urine, leg & abdominal pain, N & V

Question 22

What is the three FBC findings of autoimmune hemolytic anemia

Answer 22

Decreased Hb, increased RDW & increased nucleated RBC

Question 23

What is the two smear findings of autoimmune hemolytic anemia

Answer 23

Spherocytes & fragments

Question 24

What is the four hemolytic screen findings of autoimmune hemolytic anemia

Answer 24

LDH increased due to released during RBC hemolysis
Unconjugated bilirubin increased due to breakdown of hemoglobin
Haptoglobin decreased due to liver protein binding to hemoglobin & excreted by kidney
Reticulocyte count increase due to release of immature RBC

Question 25

What is the name of the antibody test is done to test for hemolytic disease

Answer 25

COOMBS test

Question 26

What is the direct COOMBS test

Answer 26

Testing the blood for antibodies

Question 27

What is the indirect COOMBS test

Answer 27

Testing the serum for antibodies in antenatal care

Question 28

What is the results of the COOMBS test in cold agglutinin disease

Answer 28

C3d +

Question 29

What is the results of the COOMBS test in warm AIHA

Answer 29

IgG+

Question 30

What is the results of the COOMBS test in paroxysmal cold hemoglobinuria

Answer 30

C3d & IgG +

Question 31

What is the COOMBS test limitations

Answer 31

Non specific + due to inflammation

Question 32

What is three secondary causes of AIHA

Answer 32

Infections, autoimmune & malignancies

Question 33

What is the treatment plan for cold AIHA

Answer 33

1. Self limiting & supportive treatment 2. Nutrients (folate & iron) 3. Transfusions for symptomatic anemia 4. Keep patient warm

Question 34

What is the treatment plan for warm AIHA

Answer 34

**Immunosupression** 1. Corticosteroid therapy 2. Rituximab for anti-B-cell monoclonal antibody 3. Complement inhibition 4. Severe cases a splenectomy

Question 35

What is allo-immune hemolysis

Answer 35

Antibodies to red cells received from another individual

Question 36

What is microangiopathic hemolytic anemia

Answer 36

Abnormal microcirculation due to mechanical red cell damage causing intravascular hemolysis

Question 37

What is four cause of microangiopathic hemolytic anemia

Answer 37

TTP, DIC, hemolytic uremic syndrome, malignant hypertension

Question 38

When does TTP occur

Answer 38

Newly diagnosed or poor compliance to medication HIV patients

Question 39

What is DIC

Answer 39

Abnormal activation of coagulation cascade

Question 40

How is microangiopathic hemolytic anemia diagnosed

Answer 40

Raised LDH & unconjugated bilirubin, low haptoglobin & negative DAT Low platelets, anemia, raised RDW (red cell fragments) Peripheral smear shows red cell fragments & microspherocyte Coagulation parameters to differentiate cause

Question 41

What is the management plan for microangiopathic hemolytic anemia

Answer 41

Depends on underlying cause Plasma exchange for TPP Steroids to decrease auto-antibodies Antibiotics for infections Dialysis for kidney damage