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NR-507 | Midterm Practice Examination Page 1
, R-507 MIDTERM EXAM
Advanced Pathophysiology
Chamberlain University
100-Question Original Practice Examination
2026/2027 Edition
1. An adult develops wheezing, urticaria, and hypotension minutes after a bee sting. Which mechanism most
directly initiates the reaction?
A) Allergen cross-linking of mast-cell-bound IgE
B) IgG deposition in renal capillaries
C) Cytotoxic T-cell activation after 48 hours
D) IgM destruction of circulating erythrocytes
Correct Answer: Allergen cross-linking of mast-cell-bound IgE
Rationale: Prior sensitization leaves allergen-specific IgE on mast cells. Re-exposure cross-links these receptors and
triggers mediator release, including histamine and leukotrienes. Immune-complex deposition is type III rather than the
immediate type I mechanism responsible for this presentation.
2. Several hours after receiving incompatible blood, a recipient develops hemoglobinuria and a positive direct
antiglobulin test. What mechanism best explains the injury?
A) Delayed T-cell recruitment to skin
B) IgE-mediated mast-cell degranulation
C) Antibody-mediated complement activation against erythrocyte antigens
D) Immune-complex trapping within synovium
Correct Answer: Antibody-mediated complement activation against erythrocyte antigens
Rationale: Antibodies recognizing transfused red-cell antigens activate complement and produce hemolysis, a type II
hypersensitivity process. A direct antiglobulin test supports antibody or complement coating of erythrocytes. Type I
allergy causes immediate mediator release but not this specific immune hemolysis.
3. After a streptococcal infection, a child develops edema, cola-colored urine, and low serum C3. Which
immunologic process is most consistent with these findings?
A) IgE cross-linking on airway mast cells
B) Immune-complex deposition activating complement in glomeruli
C) CD8-mediated destruction of pancreatic beta cells
D) Isolated loss of neutrophil adhesion
Correct Answer: Immune-complex deposition activating complement in glomeruli
Rationale: Postinfectious glomerulonephritis commonly involves immune complexes and complement activation within
the glomerulus. Complement consumption can lower C3. The process differs from direct antibody binding to blood-cell
surfaces and from immediate IgE-mediated hypersensitivity.
4. A nickel-containing watch produces itchy, localized dermatitis two days after skin contact. Which response
drives the eruption?
A) Circulating IgE and immediate histamine release
NR-507 | Midterm Practice Examination Page 2
, B) Immune complexes lodged in glomerular capillaries
C) Autoantibodies against erythrocyte membranes
D) Sensitized T lymphocytes and macrophage recruitment
Correct Answer: Sensitized T lymphocytes and macrophage recruitment
Rationale: Allergic contact dermatitis is a delayed type IV hypersensitivity reaction mediated by antigen-specific T cells
and inflammatory cytokines. Its typical onset is delayed by one to several days. An IgE-mediated response would
usually develop within minutes of exposure.
5. A person with untreated HIV develops recurrent opportunistic infections. Which cellular change is most
responsible?
A) Selective proliferation of erythrocytes
B) Excessive production of functional neutrophils
C) Progressive depletion and dysfunction of CD4 helper T cells
D) Permanent activation of platelet aggregation
Correct Answer: Progressive depletion and dysfunction of CD4 helper T cells
Rationale: HIV targets cells expressing CD4, especially helper T lymphocytes, gradually compromising both cell-
mediated and coordinated humoral immunity. Platelet activation does not account for the broad susceptibility to
opportunistic infections. The degree of CD4 depletion strongly tracks immune vulnerability.
6. During evaluation of recurrent bacterial sinusitis, testing shows very low immunoglobulins despite a near-
normal T-cell count. Which defense is primarily impaired?
A) Renal bicarbonate reclamation
B) Antibody-mediated opsonization and neutralization
C) Platelet adhesion at damaged vessels
D) Alveolar surfactant synthesis
Correct Answer: Antibody-mediated opsonization and neutralization
Rationale: Antibodies neutralize pathogens and facilitate phagocytosis through opsonization and complement
engagement. Marked hypogammaglobulinemia especially predisposes to recurrent infections with encapsulated
bacteria. Normal T-cell numbers do not replace adequate functional antibody production.
7. A newborn has recurrent deep bacterial infections and delayed separation of the umbilical cord. A defect in
which process is most likely?
A) Antigen-specific memory B-cell formation
B) Erythrocyte hemoglobin assembly
C) Leukocyte adhesion and migration into infected tissue
D) Immunoglobulin class switching alone
Correct Answer: Leukocyte adhesion and migration into infected tissue
Rationale: Leukocyte adhesion deficiency limits neutrophil exit from blood into infected tissues, producing recurrent
infections with poor pus formation and delayed cord separation. A pure antibody class-switching defect would not
specifically explain the distinctive leukocyte migration finding.
8. An adult with systemic lupus erythematosus develops proteinuria and red-cell casts. What is the likely
underlying renal lesion?
A) IgE-driven constriction of renal arteries
NR-507 | Midterm Practice Examination Page 3
NR-507 | Midterm Practice Examination Page 1
, R-507 MIDTERM EXAM
Advanced Pathophysiology
Chamberlain University
100-Question Original Practice Examination
2026/2027 Edition
1. An adult develops wheezing, urticaria, and hypotension minutes after a bee sting. Which mechanism most
directly initiates the reaction?
A) Allergen cross-linking of mast-cell-bound IgE
B) IgG deposition in renal capillaries
C) Cytotoxic T-cell activation after 48 hours
D) IgM destruction of circulating erythrocytes
Correct Answer: Allergen cross-linking of mast-cell-bound IgE
Rationale: Prior sensitization leaves allergen-specific IgE on mast cells. Re-exposure cross-links these receptors and
triggers mediator release, including histamine and leukotrienes. Immune-complex deposition is type III rather than the
immediate type I mechanism responsible for this presentation.
2. Several hours after receiving incompatible blood, a recipient develops hemoglobinuria and a positive direct
antiglobulin test. What mechanism best explains the injury?
A) Delayed T-cell recruitment to skin
B) IgE-mediated mast-cell degranulation
C) Antibody-mediated complement activation against erythrocyte antigens
D) Immune-complex trapping within synovium
Correct Answer: Antibody-mediated complement activation against erythrocyte antigens
Rationale: Antibodies recognizing transfused red-cell antigens activate complement and produce hemolysis, a type II
hypersensitivity process. A direct antiglobulin test supports antibody or complement coating of erythrocytes. Type I
allergy causes immediate mediator release but not this specific immune hemolysis.
3. After a streptococcal infection, a child develops edema, cola-colored urine, and low serum C3. Which
immunologic process is most consistent with these findings?
A) IgE cross-linking on airway mast cells
B) Immune-complex deposition activating complement in glomeruli
C) CD8-mediated destruction of pancreatic beta cells
D) Isolated loss of neutrophil adhesion
Correct Answer: Immune-complex deposition activating complement in glomeruli
Rationale: Postinfectious glomerulonephritis commonly involves immune complexes and complement activation within
the glomerulus. Complement consumption can lower C3. The process differs from direct antibody binding to blood-cell
surfaces and from immediate IgE-mediated hypersensitivity.
4. A nickel-containing watch produces itchy, localized dermatitis two days after skin contact. Which response
drives the eruption?
A) Circulating IgE and immediate histamine release
NR-507 | Midterm Practice Examination Page 2
, B) Immune complexes lodged in glomerular capillaries
C) Autoantibodies against erythrocyte membranes
D) Sensitized T lymphocytes and macrophage recruitment
Correct Answer: Sensitized T lymphocytes and macrophage recruitment
Rationale: Allergic contact dermatitis is a delayed type IV hypersensitivity reaction mediated by antigen-specific T cells
and inflammatory cytokines. Its typical onset is delayed by one to several days. An IgE-mediated response would
usually develop within minutes of exposure.
5. A person with untreated HIV develops recurrent opportunistic infections. Which cellular change is most
responsible?
A) Selective proliferation of erythrocytes
B) Excessive production of functional neutrophils
C) Progressive depletion and dysfunction of CD4 helper T cells
D) Permanent activation of platelet aggregation
Correct Answer: Progressive depletion and dysfunction of CD4 helper T cells
Rationale: HIV targets cells expressing CD4, especially helper T lymphocytes, gradually compromising both cell-
mediated and coordinated humoral immunity. Platelet activation does not account for the broad susceptibility to
opportunistic infections. The degree of CD4 depletion strongly tracks immune vulnerability.
6. During evaluation of recurrent bacterial sinusitis, testing shows very low immunoglobulins despite a near-
normal T-cell count. Which defense is primarily impaired?
A) Renal bicarbonate reclamation
B) Antibody-mediated opsonization and neutralization
C) Platelet adhesion at damaged vessels
D) Alveolar surfactant synthesis
Correct Answer: Antibody-mediated opsonization and neutralization
Rationale: Antibodies neutralize pathogens and facilitate phagocytosis through opsonization and complement
engagement. Marked hypogammaglobulinemia especially predisposes to recurrent infections with encapsulated
bacteria. Normal T-cell numbers do not replace adequate functional antibody production.
7. A newborn has recurrent deep bacterial infections and delayed separation of the umbilical cord. A defect in
which process is most likely?
A) Antigen-specific memory B-cell formation
B) Erythrocyte hemoglobin assembly
C) Leukocyte adhesion and migration into infected tissue
D) Immunoglobulin class switching alone
Correct Answer: Leukocyte adhesion and migration into infected tissue
Rationale: Leukocyte adhesion deficiency limits neutrophil exit from blood into infected tissues, producing recurrent
infections with poor pus formation and delayed cord separation. A pure antibody class-switching defect would not
specifically explain the distinctive leukocyte migration finding.
8. An adult with systemic lupus erythematosus develops proteinuria and red-cell casts. What is the likely
underlying renal lesion?
A) IgE-driven constriction of renal arteries
NR-507 | Midterm Practice Examination Page 3
