NR507 ADVANCED PATHOPHYSIOLOGY MIDTERM
EXAM QUESTIONS WITH ANSWERS
Hypersensitivity: Type 1
Type 1: Allergic reaction, Mediated by IgE, Inflammation due to mast cell degranulation
Local symptoms:
-itching
-rash
Systemic symptoms:
-wheezing
Most dangerous = anaphylactic reaction
systemic response of hypotension, severe bronchoconstriction
Main treatment: epinephrine reverses the effects
Hypersensitivity: Type 2
Type 2: Cytotoxic reaction; tissue specific (ex: thyroid tissue)
Macrophages are the primary effectors cells involved
Can cause tissue damage or alter function
Grave's disease (hyperthyroidism) - example of altering thyroid function, but does not
destroy thyroid tissue
,Incompatible blood type- example of cell/tissue damage that occurs; severe transfusion
reaction occurs and the transfused erythrocytes are destroyed by agglutination or
complement-mediated lysis.
Type 1 Hypersensitivity VS. Type 2 Hypersensitivity
Type 1 Hypersensitivity
Organ Specific
Antibody binds to the antigen on the cell surface
Type 2 Hypersensitivity
Not Organ Specific
Antibody binds to the soluble antigen outside the cell surface that was released into the
blood or body fluids, and the complex is then deposited in the tissues
Hypersensitivity: Type 3 - Examples
Rheumatoid arthritis: Antigen/antibodies are deposited in the joints
Systemic Lupus Erythematosus (SLE)- very closely related to autoimmunity-
antigen/antibodies deposit in organs that cause tissue damage
Hypersensitivity: Type 4
Delayed response
Does not involve antigen/antibody complexes like Types 1, 2 and 3
, Is T-cell mediated
Differentiating Between the Rash of a Type 1 vs. Type 4 Reaction:
Type 1: Immediate hypersensitivity reactions, termed atopic dermatitis, are usually
characterized by widely distributed lesions
Type 4: Contact dermatitis (delayed hypersensitivity) consists of lesions only at the site
of contact with the allergen
The key determinant is the timing of the rash:
-Type 1 = Immediate
-Type 4 = Delayed: Several days following contact, ex would be poison ivy
Treatment of Type 4 Rash
A non-severe case of contact dermatitis would be treated with topical corticosteroid.
Why not epinephrine or antihistamines?
-Epinephrine is for emergent Type 1 anaphylactic reactions. Antihistamines act on the
H1 receptors. Type 4 does not involve mast cells and H1 receptors.
Antibiotics not appropriate since not an infection
Autoimmunity
EXAM QUESTIONS WITH ANSWERS
Hypersensitivity: Type 1
Type 1: Allergic reaction, Mediated by IgE, Inflammation due to mast cell degranulation
Local symptoms:
-itching
-rash
Systemic symptoms:
-wheezing
Most dangerous = anaphylactic reaction
systemic response of hypotension, severe bronchoconstriction
Main treatment: epinephrine reverses the effects
Hypersensitivity: Type 2
Type 2: Cytotoxic reaction; tissue specific (ex: thyroid tissue)
Macrophages are the primary effectors cells involved
Can cause tissue damage or alter function
Grave's disease (hyperthyroidism) - example of altering thyroid function, but does not
destroy thyroid tissue
,Incompatible blood type- example of cell/tissue damage that occurs; severe transfusion
reaction occurs and the transfused erythrocytes are destroyed by agglutination or
complement-mediated lysis.
Type 1 Hypersensitivity VS. Type 2 Hypersensitivity
Type 1 Hypersensitivity
Organ Specific
Antibody binds to the antigen on the cell surface
Type 2 Hypersensitivity
Not Organ Specific
Antibody binds to the soluble antigen outside the cell surface that was released into the
blood or body fluids, and the complex is then deposited in the tissues
Hypersensitivity: Type 3 - Examples
Rheumatoid arthritis: Antigen/antibodies are deposited in the joints
Systemic Lupus Erythematosus (SLE)- very closely related to autoimmunity-
antigen/antibodies deposit in organs that cause tissue damage
Hypersensitivity: Type 4
Delayed response
Does not involve antigen/antibody complexes like Types 1, 2 and 3
, Is T-cell mediated
Differentiating Between the Rash of a Type 1 vs. Type 4 Reaction:
Type 1: Immediate hypersensitivity reactions, termed atopic dermatitis, are usually
characterized by widely distributed lesions
Type 4: Contact dermatitis (delayed hypersensitivity) consists of lesions only at the site
of contact with the allergen
The key determinant is the timing of the rash:
-Type 1 = Immediate
-Type 4 = Delayed: Several days following contact, ex would be poison ivy
Treatment of Type 4 Rash
A non-severe case of contact dermatitis would be treated with topical corticosteroid.
Why not epinephrine or antihistamines?
-Epinephrine is for emergent Type 1 anaphylactic reactions. Antihistamines act on the
H1 receptors. Type 4 does not involve mast cells and H1 receptors.
Antibiotics not appropriate since not an infection
Autoimmunity
