NR511 | NR511 Differential Diagnosis & Primary
Care Final Exam v1 | Questions with Correct
Answers and Expert Explanation for Each Question
| Chamberlain
1. A 24-year-old female presents with a ‘honey-colored’ crusted lesion around her nose. What
is the most likely diagnosis and appropriate initial treatment?
A. Cellulitis; Cephalexin
B. Eczema; Hydrocortisone cream
C. Herpes Simplex; Acyclovir
D. Impetigo; Mupirocin ointment
Correct Answer: D
Expert Explanation: The presence of honey-colored crusts is the classic clinical
presentation of impetigo. This condition is a highly contagious superficial skin infection
typically caused by Staphylococcus aureus or Streptococcus pyogenes. For localized lesions,
topical mupirocin is the recommended first-line treatment to eradicate the bacteria and
promote healing.
2. In the diagnostic process, which term describes the probability that a person who has the
disease will test positive?
A. Sensitivity
B. Positive Predictive Value
C. Specificity
D. Negative Predictive Value
Correct Answer: A
Expert Explanation: Sensitivity refers to the ability of a test to correctly identify those
with the disease. A highly sensitive test has a low false-negative rate, making it very useful
for screening purposes. This concept is vital in primary care to ensure that serious
conditions are not missed during initial evaluations.
3. A patient presents with a ‘curtain-like’ loss of vision in one eye and flashes of light. This
requires immediate referral for which suspected condition?
A. Cataracts
B. Glaucoma
C. Retinal Detachment
,D. Macular Degeneration
Correct Answer: C
Expert Explanation: The sudden onset of a ‘curtain’ closing over the visual field along with
photopsia (flashes) is highly suggestive of retinal detachment. This is a medical emergency
that can lead to permanent vision loss if not addressed promptly by an ophthalmologist.
Immediate referral is necessary to evaluate the need for surgical intervention.
4. Which of the following physical exam findings is most specific for Acute Otitis Media
(AOM)?
A. Tenderness of the tragus
B. Bulging of the tympanic membrane
C. Erythema of the ear canal
D. Presence of cerumen
Correct Answer: B
Expert Explanation: Bulging of the tympanic membrane is the most specific indicator of
middle ear inflammation and fluid, which characterizes Acute Otitis Media. While redness
can occur, it is less specific than the physical displacement of the membrane. Accurate
diagnosis helps prevent the unnecessary use of antibiotics for Otitis Media with Effusion.
5. According to the JNC 8 guidelines, what is the blood pressure goal for a 65-year-old patient
without diabetes or chronic kidney disease?
A. <120/80
B. <130/80
C. <140/90
D. <150/90
Correct Answer: D
Expert Explanation: The JNC 8 guidelines suggest a target blood pressure of less than
150/90 mmHg for individuals aged 60 and older who do not have diabetes or CKD. This
recommendation was made to balance the benefits of blood pressure reduction with the
risks of polypharmacy and hypotension in the elderly. However, clinicians often
individualize targets based on the latest ACC/AHA guidelines which may be more stringent.
6. Which heart murmur is typically described as a mid-systolic click followed by a late systolic
murmur?
A. Mitral Valve Prolapse
B. Mitral Regurgitation
, C. Aortic Stenosis
D. Aortic Regurgitation
Correct Answer: A
Expert Explanation: Mitral Valve Prolapse (MVP) is classically associated with a mid-
systolic click and a following murmur. This occurs when the valve leaflets bulge into the left
atrium during contraction. It is one of the most common valvular heart diseases found in
clinical practice.
7. A 45-year-old male presents with sudden onset of severe pain, redness, and swelling in his
first metatarsophalangeal joint. What is the gold standard for diagnosing this condition?
A. Serum Uric Acid level
B. X-ray of the foot
C. Trial of colchicine
D. Joint fluid aspiration for crystals
Correct Answer: D
Expert Explanation: Joint fluid aspiration showing negatively birefringent needle-shaped
crystals under polarized light is the gold standard for diagnosing gout. While elevated
serum uric acid is common, it is not definitive because levels can be normal during an acute
attack. Visualizing the crystals confirms the diagnosis and differentiates it from pseudogout
or septic arthritis.
8. What is the first-line antibiotic treatment for a healthy adult diagnosed with Community-
Acquired Pneumonia (CAP) in an area with low macrolide resistance?
A. Ciprofloxacin
B. Levofloxacin
C. Azithromycin
D. Vancomycin
Correct Answer: C
Expert Explanation: In healthy outpatients with no recent antibiotic use, a macrolide such
as Azithromycin is typically the first-line choice in areas where resistance is low.
Alternatively, doxycycline can be used as an initial treatment option. If the patient has
comorbidities or risk factors for resistance, a respiratory fluoroquinolone or beta-lactam
combination would be required.
9. A patient has a TSH level of 12.5 mIU/L and a low Free T4. What is the most appropriate
management?
A. Order a Thyroid Ultrasound
Care Final Exam v1 | Questions with Correct
Answers and Expert Explanation for Each Question
| Chamberlain
1. A 24-year-old female presents with a ‘honey-colored’ crusted lesion around her nose. What
is the most likely diagnosis and appropriate initial treatment?
A. Cellulitis; Cephalexin
B. Eczema; Hydrocortisone cream
C. Herpes Simplex; Acyclovir
D. Impetigo; Mupirocin ointment
Correct Answer: D
Expert Explanation: The presence of honey-colored crusts is the classic clinical
presentation of impetigo. This condition is a highly contagious superficial skin infection
typically caused by Staphylococcus aureus or Streptococcus pyogenes. For localized lesions,
topical mupirocin is the recommended first-line treatment to eradicate the bacteria and
promote healing.
2. In the diagnostic process, which term describes the probability that a person who has the
disease will test positive?
A. Sensitivity
B. Positive Predictive Value
C. Specificity
D. Negative Predictive Value
Correct Answer: A
Expert Explanation: Sensitivity refers to the ability of a test to correctly identify those
with the disease. A highly sensitive test has a low false-negative rate, making it very useful
for screening purposes. This concept is vital in primary care to ensure that serious
conditions are not missed during initial evaluations.
3. A patient presents with a ‘curtain-like’ loss of vision in one eye and flashes of light. This
requires immediate referral for which suspected condition?
A. Cataracts
B. Glaucoma
C. Retinal Detachment
,D. Macular Degeneration
Correct Answer: C
Expert Explanation: The sudden onset of a ‘curtain’ closing over the visual field along with
photopsia (flashes) is highly suggestive of retinal detachment. This is a medical emergency
that can lead to permanent vision loss if not addressed promptly by an ophthalmologist.
Immediate referral is necessary to evaluate the need for surgical intervention.
4. Which of the following physical exam findings is most specific for Acute Otitis Media
(AOM)?
A. Tenderness of the tragus
B. Bulging of the tympanic membrane
C. Erythema of the ear canal
D. Presence of cerumen
Correct Answer: B
Expert Explanation: Bulging of the tympanic membrane is the most specific indicator of
middle ear inflammation and fluid, which characterizes Acute Otitis Media. While redness
can occur, it is less specific than the physical displacement of the membrane. Accurate
diagnosis helps prevent the unnecessary use of antibiotics for Otitis Media with Effusion.
5. According to the JNC 8 guidelines, what is the blood pressure goal for a 65-year-old patient
without diabetes or chronic kidney disease?
A. <120/80
B. <130/80
C. <140/90
D. <150/90
Correct Answer: D
Expert Explanation: The JNC 8 guidelines suggest a target blood pressure of less than
150/90 mmHg for individuals aged 60 and older who do not have diabetes or CKD. This
recommendation was made to balance the benefits of blood pressure reduction with the
risks of polypharmacy and hypotension in the elderly. However, clinicians often
individualize targets based on the latest ACC/AHA guidelines which may be more stringent.
6. Which heart murmur is typically described as a mid-systolic click followed by a late systolic
murmur?
A. Mitral Valve Prolapse
B. Mitral Regurgitation
, C. Aortic Stenosis
D. Aortic Regurgitation
Correct Answer: A
Expert Explanation: Mitral Valve Prolapse (MVP) is classically associated with a mid-
systolic click and a following murmur. This occurs when the valve leaflets bulge into the left
atrium during contraction. It is one of the most common valvular heart diseases found in
clinical practice.
7. A 45-year-old male presents with sudden onset of severe pain, redness, and swelling in his
first metatarsophalangeal joint. What is the gold standard for diagnosing this condition?
A. Serum Uric Acid level
B. X-ray of the foot
C. Trial of colchicine
D. Joint fluid aspiration for crystals
Correct Answer: D
Expert Explanation: Joint fluid aspiration showing negatively birefringent needle-shaped
crystals under polarized light is the gold standard for diagnosing gout. While elevated
serum uric acid is common, it is not definitive because levels can be normal during an acute
attack. Visualizing the crystals confirms the diagnosis and differentiates it from pseudogout
or septic arthritis.
8. What is the first-line antibiotic treatment for a healthy adult diagnosed with Community-
Acquired Pneumonia (CAP) in an area with low macrolide resistance?
A. Ciprofloxacin
B. Levofloxacin
C. Azithromycin
D. Vancomycin
Correct Answer: C
Expert Explanation: In healthy outpatients with no recent antibiotic use, a macrolide such
as Azithromycin is typically the first-line choice in areas where resistance is low.
Alternatively, doxycycline can be used as an initial treatment option. If the patient has
comorbidities or risk factors for resistance, a respiratory fluoroquinolone or beta-lactam
combination would be required.
9. A patient has a TSH level of 12.5 mIU/L and a low Free T4. What is the most appropriate
management?
A. Order a Thyroid Ultrasound
