ADVANCED PATHOPHYSIOLOGY (WEEKS
1–4) WITH 100 QUESTIONS AND CORRECT
ANSWERS WITH DETAILED RATIONALES
GRADED A+
1.
A patient with rheumatoid arthritis develops tissue damage
caused by antibodies directed against host cells. This immune
response is classified as:
A. Type I hypersensitivity
B. Type II hypersensitivity ✅
C. Type III hypersensitivity
D. Type IV hypersensitivity
Rationale:
Type II hypersensitivity reactions involve IgG or IgM antibodies
directed against antigens on cell surfaces, leading to complement
activation and cell destruction. Rheumatoid arthritis involves
antibody-mediated injury. Type I reactions are IgE-mediated
allergic responses, Type III involves immune complex deposition,
and Type IV is T-cell mediated and delayed.
2.
,Which immunoglobulin is most abundant in mucosal secretions
and breast milk?
A. IgG
B. IgM
C. IgA ✅
D. IgE
Rationale:
IgA provides protection at mucosal surfaces such as the
respiratory and gastrointestinal tracts. IgG predominates in
serum, IgM is the first antibody produced during acute infection,
and IgE mediates allergic reactions.
3.
An elevated eosinophil count is most commonly associated with:
A. Viral infections
B. Bacterial infections
C. Parasitic infections and allergic disorders ✅
D. Autoimmune disease
Rationale:
Eosinophils play a key role in allergic responses and parasitic
defense. Viral infections typically elevate lymphocytes, bacterial
infections elevate neutrophils, and autoimmune diseases may
elevate various immune cells but not specifically eosinophils.
4.
,Which laboratory finding is most specific for iron deficiency
anemia?
A. Elevated MCV
B. Normal RDW
C. Low serum ferritin ✅
D. Increased serum iron
Rationale:
Ferritin reflects iron storage. In iron deficiency anemia, iron stores
are depleted, leading to low ferritin. MCV is decreased (not
elevated), RDW is often increased, and serum iron is low, not
high.
5.
The primary mechanism causing tissue ischemia in sickle cell
disease is:
A. Reduced erythropoietin production
B. Vaso-occlusion from sickled erythrocytes ✅
C. Increased plasma volume
D. Impaired hemoglobin synthesis
Rationale:
Sickle cell disease results from abnormal hemoglobin that
polymerizes under stress, causing red blood cells to sickle and
obstruct blood flow. Erythropoietin and hemoglobin synthesis are
not the primary problems.
6.
, Which condition results in pancytopenia due to bone marrow
failure?
A. Leukemia
B. Aplastic anemia ✅
C. Iron deficiency anemia
D. Hemolytic anemia
Rationale:
Aplastic anemia involves failure of hematopoietic stem cells,
resulting in decreased production of red cells, white cells, and
platelets. Leukemia causes abnormal proliferation, not
suppression, and iron deficiency affects only red cells.
7.
Chronic hypertension leads to left ventricular hypertrophy
primarily because of:
A. Volume overload
B. Pressure overload ✅
C. Increased preload
D. Reduced afterload
Rationale:
Sustained hypertension increases systemic vascular resistance,
creating pressure overload. The myocardium thickens to
compensate. Volume overload causes dilation rather than
hypertrophy.
8.