Type II Hypersensitivity

Question 1

Which 3 conditions result from Type II reactions?

Answer 1

1. Blood transfusion reactions
2. Hemolytic Disease of Newborns (HDN)
3. Autoimmune diseases

Question 2

What are 3 consequences of hemolysis (beside RBC lysis)?

Answer 2

1) Clotting (of RBC pieces)
2) Kidney damage
3) Anaphylatoxin release (C3a, C4a, C5a) / degranulation

Question 3

Major vs minor crossmatch

Answer 3

Major = donor's RBCs
Minor = donor's serum/plasma

Question 4

Which isohemagglutinin is worst in the cat?

Answer 4

Anti-A (b/c IgM)

Question 5

Which isohemagglutinins are present naturally in dogs, and do they cause clinically significant reactions?

Answer 5

3, 5, and 7

No, b/c cause delayed hemolysis

Question 6

Which blood groups are of clinical significance in dogs? In horses?

Answer 6

Dogs = DEA 1.1 and DEA 1.2
Horses = Aa and Qa

Question 7

Which 4 conditions must be met for HDN to occur?

Answer 7

1. Child has dissimilar blood-type
2. Mother sensitized against that blood-type by previous exposure
3. Mother further sensitized to antigen by transplacental hemorrhage
4. Newborn drinks mom’s colostrum

Question 8

Drug-induced reactions cause which types of hypersensitivity reactions?

Answer 8

All 4

Question 9

Drugs associated with hypersensitivity include

Answer 9

Penicillins, trimethoprim, and sulfonamides

Question 10

Which 4 autoimmune reactions are caused by Type II hypersensitivity?

Answer 10

1. Thrombocytopenia purpura
2. Autoimmune hemolytic anemia
3. Myasthenia gravis
4. Pemphigus

Question 11

In the bullae of bullous pemphigoid, how can type II antibody deposits be distinguished from type III?

Answer 11

Type II - ribbon-like

Type III - lumpy-bumpy