Fluid/electrolyte dysfunction
Comprehensive Final Test (Qns & Ans)
2025
Question 1 (Multiple Choice)
Question:
A 65-year-old patient presents with oliguria and elevated blood
urea nitrogen (BUN) and creatinine levels following severe
dehydration. Which of the following laboratory findings would
most likely support a diagnosis of pre-renal acute kidney injury?
A) Urine sodium concentration > 40 mEq/L
B) Fractional excretion of sodium (FeNa) < 1%
C) Presence of granular ("muddy") brown casts
D) Elevated urine osmolality < 300 mOsm/kg
Correct ANS:
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,B) Fractional excretion of sodium (FeNa) < 1%
Rationale:
Pre-renal AKI is typically characterized by a low FeNa (<1%),
reflecting robust sodium reabsorption by the kidneys in response
to decreased perfusion. In contrast, intrinsic renal injury (e.g.,
ATN) usually shows higher urine sodium, granular casts, and low
urine osmolality due to tubular damage.
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Question 2 (Fill in the Blank)
Question:
The average normal glomerular filtration rate (GFR) in a healthy
adult is approximately ________ mL/min.
Correct ANS:
120
Rationale:
A normal GFR in healthy adults is about 120 mL/min, which
reflects the overall capacity of the kidneys to filter blood. This
value is used as a baseline for assessing kidney function.
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Question 3 (True/False)
Question:
True/False: In acute tubular necrosis (ATN), the presence of
muddy brown granular casts in the urine is a hallmark finding on
urinalysis.
Correct ANS:
True
Rationale:
Muddy brown granular casts result from necrotic tubular
epithelial cells in ATN and are a classic finding on urinalysis,
helping to distinguish intrinsic renal injury from pre‑renal
azotemia.
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Question 4 (Multiple Response)
Question:
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, Select all features that are typically observed in nephrotic
syndrome:
A) Proteinuria > 3.5 g/day
B) Hypoalbuminemia
C) Hyperlipidemia
D) Hematuria with dysmorphic red blood cells
E) Edema
Correct ANS:
A, B, C, E
Rationale:
Nephrotic syndrome is characterized by heavy proteinuria (A),
low serum albumin (B), compensatory hyperlipidemia (C), and
edema (E). Hematuria with dysmorphic red blood cells (D) is
more suggestive of glomerulonephritis rather than pure nephrotic
syndrome.
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Question 5 (Multiple Choice)
Question:
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