NR 511 EXAM: ADVANCED
DIFFERENTIAL DIAGNOSIS
QUESTIONS & VERIFIED ANSWERS
2026/2027 UPDATE
1. A 45-year-old male presents with sudden onset of severe eye pain, a hazy cornea, and a
fixed, mid-dilated pupil. Which of the following is the most likely differential diagnosis?
A. Corneal Abrasion
B. Uveitis
C. Acute Angle-Closure Glaucoma
D. Bacterial Conjunctivitis
Answer: C
Conceptual Explanation: Acute angle-closure glaucoma is a medical emergency
characterized by sudden increased intraocular pressure, causing severe pain, a mid-dilated
fixed pupil, and a cloudy cornea.
2. When evaluating a diagnostic test, the probability that a person with the disease will test
positive is known as:
A. Specificity
B. Sensitivity
,C. Positive Predictive Value
D. Likelihood Ratio
Answer: B
Conceptual Explanation: Sensitivity refers to the ability of a test to correctly identify
those with the disease (true positive rate).
3. A patient presents with a ‘herald patch’ followed by a ‘Christmas tree’ distribution of
smaller maculopapular lesions. This is pathognomonic for:
A. Tinea Corporis
B. Pityriasis Rosea
C. Secondary Syphilis
D. Guttate Psoriasis
Answer: B
Conceptual Explanation: Pityriasis rosea typically begins with a herald patch, followed by
smaller lesions along skin cleavage lines, resembling a Christmas tree pattern.
4. Which physical exam finding is most specific for Acute Cholecystitis?
A. Rovsing’s Sign
B. McBurney’s Point tenderness
C. Murphy’s Sign
, D. Psoas Sign
Answer: C
Conceptual Explanation: Murphy’s sign (pain and inspiratory arrest upon palpation of the
gallbladder during deep inspiration) is highly specific for acute cholecystitis.
5. In the differential diagnosis of microcytic anemia, a Mentzer Index (MCV/RBC count) of less
than 13 strongly suggests:
A. Thalassemia
B. Anemia of Chronic Disease
C. Iron Deficiency Anemia
D. Sideroblastic Anemia
Answer: A
Conceptual Explanation: A Mentzer index less than 13 is characteristic of Thalassemia,
whereas a value greater than 13 usually indicates iron deficiency anemia.
6. A 60-year-old smoker presents with painless hematuria. What must be ruled out as a
primary differential?
A. Nephrolithiasis
B. Bladder Cancer
C. Prostatitis
D. Glomerulonephritis
DIFFERENTIAL DIAGNOSIS
QUESTIONS & VERIFIED ANSWERS
2026/2027 UPDATE
1. A 45-year-old male presents with sudden onset of severe eye pain, a hazy cornea, and a
fixed, mid-dilated pupil. Which of the following is the most likely differential diagnosis?
A. Corneal Abrasion
B. Uveitis
C. Acute Angle-Closure Glaucoma
D. Bacterial Conjunctivitis
Answer: C
Conceptual Explanation: Acute angle-closure glaucoma is a medical emergency
characterized by sudden increased intraocular pressure, causing severe pain, a mid-dilated
fixed pupil, and a cloudy cornea.
2. When evaluating a diagnostic test, the probability that a person with the disease will test
positive is known as:
A. Specificity
B. Sensitivity
,C. Positive Predictive Value
D. Likelihood Ratio
Answer: B
Conceptual Explanation: Sensitivity refers to the ability of a test to correctly identify
those with the disease (true positive rate).
3. A patient presents with a ‘herald patch’ followed by a ‘Christmas tree’ distribution of
smaller maculopapular lesions. This is pathognomonic for:
A. Tinea Corporis
B. Pityriasis Rosea
C. Secondary Syphilis
D. Guttate Psoriasis
Answer: B
Conceptual Explanation: Pityriasis rosea typically begins with a herald patch, followed by
smaller lesions along skin cleavage lines, resembling a Christmas tree pattern.
4. Which physical exam finding is most specific for Acute Cholecystitis?
A. Rovsing’s Sign
B. McBurney’s Point tenderness
C. Murphy’s Sign
, D. Psoas Sign
Answer: C
Conceptual Explanation: Murphy’s sign (pain and inspiratory arrest upon palpation of the
gallbladder during deep inspiration) is highly specific for acute cholecystitis.
5. In the differential diagnosis of microcytic anemia, a Mentzer Index (MCV/RBC count) of less
than 13 strongly suggests:
A. Thalassemia
B. Anemia of Chronic Disease
C. Iron Deficiency Anemia
D. Sideroblastic Anemia
Answer: A
Conceptual Explanation: A Mentzer index less than 13 is characteristic of Thalassemia,
whereas a value greater than 13 usually indicates iron deficiency anemia.
6. A 60-year-old smoker presents with painless hematuria. What must be ruled out as a
primary differential?
A. Nephrolithiasis
B. Bladder Cancer
C. Prostatitis
D. Glomerulonephritis
