MSN Advanced Pathophysiology 1 — Questions and Answers
Question 1: Which mechanism primarily causes the symptoms of heart failure?
- Compensatory neurohormonal activation leading to fluid retention (Correct answer)
- Excessive red blood cell production
- Decreased platelet aggregation
- Hyperactivation of the parasympathetic nervous system
Correct answer: Compensatory neurohormonal activation leading to fluid retention
In heart failure, the renin-angiotensin-aldosterone system and sympathetic nervous system activate compensatorily, leading to sodium and water retention that worsens congestion.
Question 2: In type 2 diabetes mellitus, which pathophysiological process is most central?
- Absolute insulin deficiency due to beta cell destruction
- Peripheral insulin resistance combined with progressive beta cell dysfunction (Correct answer)
- Excess glucagon secretion only
- Autoimmune destruction of alpha cells
Correct answer: Peripheral insulin resistance combined with progressive beta cell dysfunction
Type 2 DM is characterized by peripheral insulin resistance and gradual beta cell failure, unlike Type 1 which involves autoimmune destruction.
Question 3: Which inflammatory mediator is primarily responsible for fever during an acute infection?
- Interleukin-1 (IL-1) and prostaglandin E2 (Correct answer)
- Thromboxane A2
- Bradykinin alone
- Complement C3a
Correct answer: Interleukin-1 (IL-1) and prostaglandin E2
IL-1 stimulates the hypothalamus to increase prostaglandin E2 synthesis, which resets the thermoregulatory set point upward causing fever.
Question 4: A patient develops acute respiratory distress syndrome (ARDS). Which pathophysiological change occurs first?
- Pulmonary fibrosis
- Diffuse alveolar damage with increased capillary permeability (Correct answer)
- Right ventricular hypertrophy
- Pleural effusion
Correct answer: Diffuse alveolar damage with increased capillary permeability
ARDS begins with diffuse alveolar damage that increases pulmonary capillary permeability, allowing protein-rich fluid to flood the alveoli.
Question 5: In chronic kidney disease, which compensatory mechanism initially maintains glomerular filtration rate?
- Hyperfiltration in remaining nephrons (Correct answer)
- Increased erythropoietin secretion
- Decreased renin release
- Hyperparathyroidism
Correct answer: Hyperfiltration in remaining nephrons
Remaining functional nephrons undergo hyperfiltration to compensate for nephron loss, which temporarily maintains GFR but accelerates further injury.
Question 6: Which mechanism explains the hypercoagulability seen in malignancy-associated thrombosis?
- Tumor cells expressing tissue factor that activates the extrinsic coagulation pathway (Correct answer)
- Excessive platelet destruction
- Deficiency of von Willebrand factor
- Overproduction of protein C
Correct answer: Tumor cells expressing tissue factor that activates the extrinsic coagulation pathway
Many tumor cells express tissue factor on their surface, directly activating the extrinsic coagulation cascade and creating a prothrombotic state.
MSN Advanced Pathophysiology 1
Which mechanism primarily causes the symptoms of heart failure?