type 2 hypersensitivity, signs, clinical features and management

Question 1

what are the 3 mechansims of type 3 hypersensitiviy

Answer 1

1. Activation of complement by IgG- osmotic cell lysis
2. Antibody acts as an oponin and enhances phagocytosis
3. Antibody binds cell-surface antigens -> ADCC

Question 2

Give an example of type 2 hypersesiticty

Answer 2

1. Immune haemolytic anaemia

• ​Acute haemolytic anaemia
• Drug induced haemolytic anemia

Question 3

explain acute haemolytic anemia

Answer 3

Acute haemolytic transfusion reaction

• ABO incompatibility - lysis of donor cells by preformed IgG
• Managment: ABC, fluids and pharmachological BP support

Question 4

Explain drug induce anemia

Answer 4

• Penicillin allergy
• 20 year old women with UTI given penillin even though previously no reaction

Question 5

What will be the clinical features of haemolytic anemia

Answer 5

• Hypotension
• Increases RR

Question 6

What would the managment of type hameolytic anaemic be

Answer 6

1. Plasmaparesis

• ​Blood removed and separated to remove pathogenic antibody
• 50% plasma removed each time
• Plasma can be replaced with someones
• Cell contents can be replaced or pooled immunoglobulin - limmitation = rebound antibody

​​ 2. Immune supression - potent agent stop B-cell production