PATHOPHYSIOLOGY | QUESTIONS AND VERIFIED ANSWERS| 100%
CORRECT |GRADE A + CHAMBERLAIN
1) A 55-year-old patient presents with fatigue, pallor, and dyspnea. Labs reveal
hemoglobin 8 g/dL, MCV 70 fL, and low ferritin. Which type of anemia is most
likely?
A. Vitamin B12 deficiency anemia
B. Iron-deficiency anemia
C. Aplastic anemia
D. Hemolytic anemia
Rationale:
Microcytic anemia (MCV <80 fL) with low ferritin and clinical fatigue strongly
suggests iron-deficiency anemia, often due to chronic blood loss or dietary
deficiency. B12 deficiency is macrocytic (high MCV), aplastic anemia shows
pancytopenia, and hemolytic anemia often presents with elevated reticulocytes.
2) Which cytokine is primarily responsible for inducing fever during an acute
inflammatory response?
A. Interleukin-10 (IL-10)
B. Interleukin-1 (IL-1)
C. Tumor necrosis factor-beta (TNF-β)
D. Transforming growth factor-beta (TGF-β)
Rationale:
IL-1, along with TNF-α, acts on the hypothalamus to induce fever during
inflammation. IL-10 and TGF-β are anti-inflammatory cytokines. TNF-β has a
minor role in immune regulation, not fever induction.
,3) A patient with type 2 diabetes presents with polyuria, polydipsia, and serum
glucose 480 mg/dL. Which pathophysiologic mechanism is responsible for the
hyperglycemia?
A. Excess insulin secretion
B. Autoimmune beta-cell destruction
C. Insulin resistance and relative insulin deficiency
D. Decreased gluconeogenesis
Rationale:
Type 2 diabetes is characterized by insulin resistance in peripheral tissues and
relative insulin deficiency over time. Autoimmune beta-cell destruction is typical
of type 1 diabetes. Polyuria and hyperglycemia result from osmotic diuresis due to
elevated plasma glucose.
4) Which electrolyte imbalance is most likely in a patient with chronic kidney
disease?
A. Hypokalemia
B. Hypocalcemia
C. Hypernatremia
D. Hyperkalemia
Rationale:
Hyperkalemia is common in CKD due to impaired renal potassium excretion.
Hypocalcemia may occur but is secondary to hyperphosphatemia and vitamin D
deficiency. Sodium levels are often normal, and hypokalemia is more common
with diuretics.
5) Which mechanism best explains the development of atherosclerosis?
A. Decreased LDL oxidation
B. Increased HDL cholesterol deposition
C. Endothelial injury leading to lipid accumulation and inflammation
D. Vasodilation of arterial smooth muscle
,Rationale:
Atherosclerosis begins with endothelial injury, which increases permeability to
LDL, followed by oxidation, macrophage uptake, foam cell formation, and
inflammatory cytokine release. HDL helps remove cholesterol (protective).
Vasodilation does not cause plaque formation.
6) A patient presents with jaundice, dark urine, and elevated unconjugated
bilirubin. Which type of jaundice is most likely?
A. Obstructive (posthepatic)
B. Hemolytic (prehepatic)
C. Hepatocellular (intrahepatic)
D. Gilbert’s syndrome
Rationale:
Hemolytic jaundice is characterized by elevated unconjugated bilirubin due to
excessive RBC breakdown. Obstructive jaundice elevates conjugated bilirubin,
hepatocellular jaundice elevates both conjugated and unconjugated bilirubin, and
Gilbert’s is a mild genetic form with intermittent unconjugated bilirubin elevation.
7) Which pathophysiologic change occurs in left-sided heart failure?
A. Peripheral edema only
B. Pulmonary congestion and dyspnea
C. Hypervolemia without pulmonary involvement
D. Systemic hypotension without pulmonary symptoms
Rationale:
Left-sided heart failure leads to elevated left atrial pressure, causing pulmonary
venous congestion and symptoms like dyspnea and orthopnea. Peripheral edema is
more typical of right-sided failure. Systemic hypotension may occur in advanced
stages but is not primary.
8) A patient with chronic obstructive pulmonary disease (COPD) develops
hypercapnia. Which acid-base disorder is expected?
, A. Metabolic acidosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Respiratory alkalosis
Rationale:
COPD causes hypoventilation, leading to CO2 retention and respiratory
acidosis. The kidneys may compensate over time by retaining bicarbonate.
Respiratory alkalosis occurs with hyperventilation.
9) Which of the following best describes the pathophysiology of type 1 diabetes
mellitus?
A. Insulin resistance in peripheral tissues
B. Autoimmune destruction of pancreatic beta cells
C. Excess glucagon secretion
D. Decreased hepatic gluconeogenesis
Rationale:
Type 1 diabetes is caused by autoimmune destruction of beta cells, leading to
absolute insulin deficiency. Type 2 diabetes involves insulin resistance. Excess
glucagon can exacerbate hyperglycemia but is not the primary cause.
10) Which is the most common cause of hyperthyroidism in the United States?
A. Toxic multinodular goiter
B. Thyroid carcinoma
C. Graves’ disease
D. Iodine deficiency
Rationale:
Graves’ disease is the most common cause of hyperthyroidism, caused by
autoimmune stimulation of TSH receptors. Toxic multinodular goiter is more
common in older adults, and thyroid carcinoma rarely causes hyperthyroidism.