NR 283 Pathophysiology Final Comprehensive
Exam | Questions and Answers + Expert Rationales
| 2026/27 Updated | 100% correct | Chamberlain
1. Nephrotoxins, ischemia, pyelonephritis, hypoperfusion, hypotension, severe circulatory
shock, heart failure, and mechanical obstructions all cause which type of acute kidney injury
(AKI)?
A) Intrarenal AKI
B) Post-renal AKI
C) Pre-renal AKI
D) chronic kidney disease
Correct Answer: C. Pre-renal AKI
Expert Rationale: Pre-renal AKI results from conditions that decrease renal blood flow, leading
to decreased glomerular perfusion. These include nephrotoxins (toxic to kidney tissue),
ischemia (reduced blood flow), pyelonephritis (kidney infection), hypoperfusion (inadequate
blood supply), hypotension, severe circulatory shock, heart failure, and mechanical
obstructions. These factors reduce the pressure gradient needed for glomerular filtration,
causing acute kidney injury.
2. Calculi (kidney stones), blood clots, and tumors are mechanical obstructions that block
urine flow beyond the kidneys and cause what condition?
A) Pre-renal AKI
B) Acute renal failure (post-renal AKI)
C) chronic kidney disease
D) Nephrotic syndrome
Correct Answer: B. Acute renal failure (post-renal AKI)
Expert Rationale: Post-renal AKI is caused by mechanical obstructions that block urine flow
after it leaves the kidneys. Calculi (kidney stones), blood clots, and tumors can obstruct the
ureters, bladder, or urethra. This obstruction increases pressure in the renal tubules, reducing
glomerular filtration and leading to acute renal failure. Unlike pre-renal causes, these
obstructions physically prevent urine from exiting the urinary tract.
,3. Drugs, chemicals, and toxins that cause tubule necrosis and obstruction of blood flow are
termed:
A) Pyrogens
B) Nephrotoxins
C) Teratogens
D) Carcinogens
Correct Answer: B. Nephrotoxins
Expert Rationale: Nephrotoxins are substances that are toxic to the kidneys. They cause
damage to the renal tubules (tubular necrosis) and can obstruct blood flow within the kidney.
Common nephrotoxins include certain antibiotics (aminoglycosides), contrast dyes, NSAIDs, and
heavy metals. This damage leads to acute tubular necrosis (ATN), a form of intrarenal AKI.
Unlike pre-renal causes, nephrotoxins directly damage kidney tissue .
4. Polyuria, lethargy, oliguria, uremia, retention of fluids/electrolytes/wastes, and anuria are
clinical manifestations of which condition?
A) Acute kidney injury (AKI)
B) Chronic kidney disease (CKD)
C) Urinary tract infection
D) Nephrotic syndrome
Correct Answer: B. Chronic kidney disease (CKD)
Expert Rationale: Chronic kidney disease is characterized by progressive, irreversible loss of
renal function. Clinical manifestations include:
• Polyuria (early in CKD when the kidneys cannot concentrate urine)
• Lethargy (from accumulation of uremic toxins)
• Oliguria (decreased urine output as disease progresses)
• Uremia (accumulation of nitrogenous wastes)
• Fluid, electrolyte, and waste retention
• Anuria (complete absence of urine in end-stage disease)
CKD develops gradually over months to years, unlike the rapid onset of AKI .
,5. What is the glomerular filtration rate (GFR) for CKD stage 5/end-stage renal disease (ESRD)?
A) 60-89 mL/min
B) 30-59 mL/min
C) 15-29 mL/min
D) 15 mL/min or less
Correct Answer: D. 15 mL/min or less
Expert Rationale: CKD stage 5 (end-stage renal disease) is defined as a GFR of 15 mL/min or
less. At this stage, kidney function is severely compromised, and the patient requires renal
replacement therapy (dialysis or transplantation) to survive. Normal GFR is 90-120 mL/min.
Stage 3 is 30-59 mL/min, and stage 4 is 15-29 mL/min. ESRD represents the final, irreversible
stage of chronic kidney disease .
6. What is a normal reading for specific gravity in urine for someone who is well hydrated?
A) 1.001-1.005
B) 1.010-1.025
C) 1.030
D) 1.035 or higher
Correct Answer: B. 1.010-1.025
Expert Rationale: Specific gravity measures urine concentration. Normal urine specific gravity
ranges from 1.010 to 1.025 in a well-hydrated person. The document states 1.030 as the
hydrated value, but standard reference ranges show 1.010-1.025 is typical. Dehydration
increases specific gravity to 1.035 or higher. Low specific gravity (<1.010) suggests dilute urine
(e.g., diabetes insipidus, excessive fluid intake) .
7. If a patient came in dehydrated, what would you expect their urine specific gravity to be?
A) 1.001-1.005
B) 1.010-1.025
C) 1.030
D) 1.035 or higher
Correct Answer: D. 1.035 or higher
Expert Rationale: Dehydration leads to concentrated urine, with specific gravity typically 1.035
or higher. The kidneys conserve water by increasing urine concentration. This is a compensatory
, mechanism in response to fluid deficit. A specific gravity greater than 1.035 indicates significant
dehydration or conditions with increased ADH secretion (SIADH). A lower specific gravity in a
dehydrated patient suggests impaired concentrating ability (e.g., diabetes insipidus, renal
disease) .
8. What hormone is produced by the renal system in response to high hypertension?
A) Erythropoietin
B) Renin
C) Aldosterone
D) ADH
Correct Answer: B. Renin
Expert Rationale: Renin is an enzyme produced by the juxtaglomerular cells of the kidneys in
response to decreased renal perfusion pressure (e.g., hypotension, hypovolemia, or renal artery
stenosis). It is NOT produced in response to high hypertension. Renin activates the renin-
angiotensin-aldosterone system (RAAS), leading to vasoconstriction and sodium/water retention
to increase blood pressure. Renin-blocking drugs (beta-blockers) are used to treat hypertension
by inhibiting this pathway .
9. A patient with a bladder tumor is most likely to have what kind of acute renal injury?
A) Pre-renal AKI
B) Intrarenal AKI
C) Post-renal AKI
D) Chronic kidney disease
Correct Answer: C. Post-renal AKI
Expert Rationale: A bladder tumor can obstruct urine flow out of the bladder, causing post-
renal AKI. This is a mechanical obstruction that blocks urine flow beyond the kidneys. The
obstruction increases pressure in the renal tubules, reducing glomerular filtration rate (GFR) and
leading to acute kidney injury. Post-renal AKI is reversible if the obstruction is relieved promptly.
Pre-renal causes involve decreased blood flow; intrarenal causes involve direct kidney damage .
10. A patient with obstruction of the renal artery causing renal ischemia exhibits
hypertension. What is one factor that may contribute to this hypertension?
Exam | Questions and Answers + Expert Rationales
| 2026/27 Updated | 100% correct | Chamberlain
1. Nephrotoxins, ischemia, pyelonephritis, hypoperfusion, hypotension, severe circulatory
shock, heart failure, and mechanical obstructions all cause which type of acute kidney injury
(AKI)?
A) Intrarenal AKI
B) Post-renal AKI
C) Pre-renal AKI
D) chronic kidney disease
Correct Answer: C. Pre-renal AKI
Expert Rationale: Pre-renal AKI results from conditions that decrease renal blood flow, leading
to decreased glomerular perfusion. These include nephrotoxins (toxic to kidney tissue),
ischemia (reduced blood flow), pyelonephritis (kidney infection), hypoperfusion (inadequate
blood supply), hypotension, severe circulatory shock, heart failure, and mechanical
obstructions. These factors reduce the pressure gradient needed for glomerular filtration,
causing acute kidney injury.
2. Calculi (kidney stones), blood clots, and tumors are mechanical obstructions that block
urine flow beyond the kidneys and cause what condition?
A) Pre-renal AKI
B) Acute renal failure (post-renal AKI)
C) chronic kidney disease
D) Nephrotic syndrome
Correct Answer: B. Acute renal failure (post-renal AKI)
Expert Rationale: Post-renal AKI is caused by mechanical obstructions that block urine flow
after it leaves the kidneys. Calculi (kidney stones), blood clots, and tumors can obstruct the
ureters, bladder, or urethra. This obstruction increases pressure in the renal tubules, reducing
glomerular filtration and leading to acute renal failure. Unlike pre-renal causes, these
obstructions physically prevent urine from exiting the urinary tract.
,3. Drugs, chemicals, and toxins that cause tubule necrosis and obstruction of blood flow are
termed:
A) Pyrogens
B) Nephrotoxins
C) Teratogens
D) Carcinogens
Correct Answer: B. Nephrotoxins
Expert Rationale: Nephrotoxins are substances that are toxic to the kidneys. They cause
damage to the renal tubules (tubular necrosis) and can obstruct blood flow within the kidney.
Common nephrotoxins include certain antibiotics (aminoglycosides), contrast dyes, NSAIDs, and
heavy metals. This damage leads to acute tubular necrosis (ATN), a form of intrarenal AKI.
Unlike pre-renal causes, nephrotoxins directly damage kidney tissue .
4. Polyuria, lethargy, oliguria, uremia, retention of fluids/electrolytes/wastes, and anuria are
clinical manifestations of which condition?
A) Acute kidney injury (AKI)
B) Chronic kidney disease (CKD)
C) Urinary tract infection
D) Nephrotic syndrome
Correct Answer: B. Chronic kidney disease (CKD)
Expert Rationale: Chronic kidney disease is characterized by progressive, irreversible loss of
renal function. Clinical manifestations include:
• Polyuria (early in CKD when the kidneys cannot concentrate urine)
• Lethargy (from accumulation of uremic toxins)
• Oliguria (decreased urine output as disease progresses)
• Uremia (accumulation of nitrogenous wastes)
• Fluid, electrolyte, and waste retention
• Anuria (complete absence of urine in end-stage disease)
CKD develops gradually over months to years, unlike the rapid onset of AKI .
,5. What is the glomerular filtration rate (GFR) for CKD stage 5/end-stage renal disease (ESRD)?
A) 60-89 mL/min
B) 30-59 mL/min
C) 15-29 mL/min
D) 15 mL/min or less
Correct Answer: D. 15 mL/min or less
Expert Rationale: CKD stage 5 (end-stage renal disease) is defined as a GFR of 15 mL/min or
less. At this stage, kidney function is severely compromised, and the patient requires renal
replacement therapy (dialysis or transplantation) to survive. Normal GFR is 90-120 mL/min.
Stage 3 is 30-59 mL/min, and stage 4 is 15-29 mL/min. ESRD represents the final, irreversible
stage of chronic kidney disease .
6. What is a normal reading for specific gravity in urine for someone who is well hydrated?
A) 1.001-1.005
B) 1.010-1.025
C) 1.030
D) 1.035 or higher
Correct Answer: B. 1.010-1.025
Expert Rationale: Specific gravity measures urine concentration. Normal urine specific gravity
ranges from 1.010 to 1.025 in a well-hydrated person. The document states 1.030 as the
hydrated value, but standard reference ranges show 1.010-1.025 is typical. Dehydration
increases specific gravity to 1.035 or higher. Low specific gravity (<1.010) suggests dilute urine
(e.g., diabetes insipidus, excessive fluid intake) .
7. If a patient came in dehydrated, what would you expect their urine specific gravity to be?
A) 1.001-1.005
B) 1.010-1.025
C) 1.030
D) 1.035 or higher
Correct Answer: D. 1.035 or higher
Expert Rationale: Dehydration leads to concentrated urine, with specific gravity typically 1.035
or higher. The kidneys conserve water by increasing urine concentration. This is a compensatory
, mechanism in response to fluid deficit. A specific gravity greater than 1.035 indicates significant
dehydration or conditions with increased ADH secretion (SIADH). A lower specific gravity in a
dehydrated patient suggests impaired concentrating ability (e.g., diabetes insipidus, renal
disease) .
8. What hormone is produced by the renal system in response to high hypertension?
A) Erythropoietin
B) Renin
C) Aldosterone
D) ADH
Correct Answer: B. Renin
Expert Rationale: Renin is an enzyme produced by the juxtaglomerular cells of the kidneys in
response to decreased renal perfusion pressure (e.g., hypotension, hypovolemia, or renal artery
stenosis). It is NOT produced in response to high hypertension. Renin activates the renin-
angiotensin-aldosterone system (RAAS), leading to vasoconstriction and sodium/water retention
to increase blood pressure. Renin-blocking drugs (beta-blockers) are used to treat hypertension
by inhibiting this pathway .
9. A patient with a bladder tumor is most likely to have what kind of acute renal injury?
A) Pre-renal AKI
B) Intrarenal AKI
C) Post-renal AKI
D) Chronic kidney disease
Correct Answer: C. Post-renal AKI
Expert Rationale: A bladder tumor can obstruct urine flow out of the bladder, causing post-
renal AKI. This is a mechanical obstruction that blocks urine flow beyond the kidneys. The
obstruction increases pressure in the renal tubules, reducing glomerular filtration rate (GFR) and
leading to acute kidney injury. Post-renal AKI is reversible if the obstruction is relieved promptly.
Pre-renal causes involve decreased blood flow; intrarenal causes involve direct kidney damage .
10. A patient with obstruction of the renal artery causing renal ischemia exhibits
hypertension. What is one factor that may contribute to this hypertension?
