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CERTIFIED DIALYSIS NURSE (CDN) Newest Exam
Preparation With Complete Questions And Correct
Answers With Rationales Already Graded A+Brand
New Version!!
QUESTION 1
Which structure of the nephron is primarily responsible for the
reabsorption of the majority of filtered sodium?
A) Proximal convoluted tubule
B) Loop of Henle (descending limb)
C) Distal convoluted tubule
D) Collecting duct
Answer: A
Explanation: The proximal convoluted tubule reabsorbs about 65% of
filtered sodium, along with water, glucose, and amino acids. This makes
it the primary site for sodium reabsorption in the nephron.
QUESTION 2
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The primary hormonal function of the kidneys in calcium homeostasis is
the activation of which vitamin?
A) Vitamin A
B) Vitamin B12
C) Vitamin D (calcitriol)
D) Vitamin K
Answer: C
Explanation: The kidneys convert 25-hydroxyvitamin D to its active
form, 1,25-dihydroxyvitamin D (calcitriol), which increases intestinal
calcium absorption. This is a critical hormonal function of the kidneys.
QUESTION 3
In prerenal acute kidney injury, which of the following laboratory
findings is most typical?
A) BUN/Creatinine ratio >20:1
B) Fractional excretion of sodium (FeNa) >2%
C) Urine sodium >40 mEq/L
D) Presence of granular casts
Answer: A
Explanation: Prerenal AKI often shows a BUN/Cr ratio >20 due to
increased urea reabsorption secondary to low renal perfusion. This
distinguishes it from intrinsic renal causes.
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QUESTION 4
Which of the following is NOT a common cause of post-renal
obstruction?
A) Benign prostatic hyperplasia
B) Ureteral calculi
C) Acute tubular necrosis
D) Bladder tumor
Answer: C
Explanation: Acute tubular necrosis is an intrinsic renal cause of acute
kidney injury, not a post-renal obstructive condition. Post-renal causes
involve obstruction of urine outflow.
QUESTION 5
The glomerular filtration rate (GFR) is most accurately estimated using
which equation in adult patients?
A) Cockcroft-Gault formula
B) Modification of Diet in Renal Disease (MDRD) equation
C) CKD-EPI equation
D) Schwartz formula
Answer: C
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Explanation: The CKD-EPI equation is currently recommended for
estimating GFR in adults as it provides greater accuracy across a range
of GFR values compared to other equations.
QUESTION 6
A patient with chronic renal failure asks the nurse why he is anemic.
The nurse explains that anemia accompanies chronic renal failure
secondary to:
A) Blood loss via the urine
B) Renal insensitivity to vitamin A (retinol)
C) Inadequate production of erythropoietin
D) Inadequate retention of serum iron
Answer: C
Explanation: The kidney is sensitive to oxygen saturation and secretes
erythropoietin as needed to signal the bone marrow to produce more
red blood cells. When the kidneys fail, erythropoietin production
decreases and eventually stops, causing anemia.
QUESTION 7
Functions of the kidney include:
A) Formation of urine
B) Regulation of body water and electrolytes
C) Acid-base balance
CERTIFIED DIALYSIS NURSE (CDN) Newest Exam
Preparation With Complete Questions And Correct
Answers With Rationales Already Graded A+Brand
New Version!!
QUESTION 1
Which structure of the nephron is primarily responsible for the
reabsorption of the majority of filtered sodium?
A) Proximal convoluted tubule
B) Loop of Henle (descending limb)
C) Distal convoluted tubule
D) Collecting duct
Answer: A
Explanation: The proximal convoluted tubule reabsorbs about 65% of
filtered sodium, along with water, glucose, and amino acids. This makes
it the primary site for sodium reabsorption in the nephron.
QUESTION 2
,2|Page
The primary hormonal function of the kidneys in calcium homeostasis is
the activation of which vitamin?
A) Vitamin A
B) Vitamin B12
C) Vitamin D (calcitriol)
D) Vitamin K
Answer: C
Explanation: The kidneys convert 25-hydroxyvitamin D to its active
form, 1,25-dihydroxyvitamin D (calcitriol), which increases intestinal
calcium absorption. This is a critical hormonal function of the kidneys.
QUESTION 3
In prerenal acute kidney injury, which of the following laboratory
findings is most typical?
A) BUN/Creatinine ratio >20:1
B) Fractional excretion of sodium (FeNa) >2%
C) Urine sodium >40 mEq/L
D) Presence of granular casts
Answer: A
Explanation: Prerenal AKI often shows a BUN/Cr ratio >20 due to
increased urea reabsorption secondary to low renal perfusion. This
distinguishes it from intrinsic renal causes.
,3|Page
QUESTION 4
Which of the following is NOT a common cause of post-renal
obstruction?
A) Benign prostatic hyperplasia
B) Ureteral calculi
C) Acute tubular necrosis
D) Bladder tumor
Answer: C
Explanation: Acute tubular necrosis is an intrinsic renal cause of acute
kidney injury, not a post-renal obstructive condition. Post-renal causes
involve obstruction of urine outflow.
QUESTION 5
The glomerular filtration rate (GFR) is most accurately estimated using
which equation in adult patients?
A) Cockcroft-Gault formula
B) Modification of Diet in Renal Disease (MDRD) equation
C) CKD-EPI equation
D) Schwartz formula
Answer: C
, 4|Page
Explanation: The CKD-EPI equation is currently recommended for
estimating GFR in adults as it provides greater accuracy across a range
of GFR values compared to other equations.
QUESTION 6
A patient with chronic renal failure asks the nurse why he is anemic.
The nurse explains that anemia accompanies chronic renal failure
secondary to:
A) Blood loss via the urine
B) Renal insensitivity to vitamin A (retinol)
C) Inadequate production of erythropoietin
D) Inadequate retention of serum iron
Answer: C
Explanation: The kidney is sensitive to oxygen saturation and secretes
erythropoietin as needed to signal the bone marrow to produce more
red blood cells. When the kidneys fail, erythropoietin production
decreases and eventually stops, causing anemia.
QUESTION 7
Functions of the kidney include:
A) Formation of urine
B) Regulation of body water and electrolytes
C) Acid-base balance
