1
Final Exam: NR 576/ NR576 (Latest 2026/ 2027 Update)
Differential Diagnosis in Adult-Gerontology Primary Care
Guide |Questions with Verified Answers| Grade A| 100%
Correct -Chamberlain.
Module 1: Foundations of Differential Diagnosis & Hematology
Question 1
A 72-year-old patient presents with fatigue, pallor, and dyspnea on exertion. Labs reveal macrocytic
anemia (MCV > 100 fL). Which additional lab finding would be most consistent with pernicious anemia?
• A) Low serum B12 with positive anti-intrinsic factor antibodies ✅
• B) Low serum folate with normal B12
• C) High ferritin with low TIBC
• D) Normal B12 with high methylmalonic acid
Rationale: Pernicious anemia is caused by B12 deficiency due to lack of intrinsic factor, leading to
macrocytic anemia. Anti-intrinsic factor antibodies are highly specific for pernicious anemia. While
elevated methylmalonic acid is also a marker for B12 deficiency, the question asks for the finding most
consistent with the diagnosis. Positive anti-intrinsic factor antibodies are the hallmark of pernicious
anemia.
Question 2
A 68-year-old woman with a history of chronic kidney disease presents with fatigue. Labs show
microcytic anemia (MCV 72 fL), low ferritin, and elevated TIBC. Which is the most likely diagnosis?
• A) Anemia of chronic disease
• B) Sideroblastic anemia
• C) Iron deficiency anemia ✅
• D) Thalassemia trait
Rationale: This pattern (low ferritin, high TIBC) is classic for iron deficiency anemia. Anemia of chronic
disease typically presents with normal or high ferritin and low TIBC.
,2
Question 3
A patient with a history of heavy alcohol use presents with macrocytic anemia. Which test is most useful
to differentiate B12 deficiency from folate deficiency?
• A) Methylmalonic acid (MMA) level ✅
• B) Homocysteine level
• C) Complete blood count (CBC)
• D) Peripheral smear
Rationale: Both B12 and folate deficiencies cause elevated homocysteine, but only B12 deficiency
causes elevated MMA. Measuring MMA is the best way to distinguish them.
Question 4
A 70-year-old man presents with unintentional weight loss, early satiety, and massive splenomegaly. His
CBC shows leukocytosis with a left shift and thrombocytosis. The most likely diagnosis is:
• A) Chronic lymphocytic leukemia (CLL)
• B) Chronic myeloid leukemia (CML) ✅
• C) Polycythemia vera (PV)
• D) Myelodysplastic syndrome (MDS)
Rationale: Massive splenomegaly, leukocytosis with a left shift, and thrombocytosis are classic for CML,
especially in older adults. The presence of the Philadelphia chromosome is diagnostic.
❖ Module 2: Dermatology
Question 5
A 45-year-old farmer presents with a rough, scaly, erythematous patch on his dorsal hand that has been
present for several months. It is not painful or pruritic. Which is the most likely diagnosis?
• A) Basal cell carcinoma
• B) Squamous cell carcinoma
• C) Actinic keratosis ✅
• D) Seborrheic keratosis
,3
Rationale: Actinic keratosis presents as a rough, scaly, erythematous patch on sun-exposed skin. It is
considered a precancerous lesion and may progress to squamous cell carcinoma. Seborrheic keratosis
has a “stuck-on” appearance.
Question 6
A 28-year-old woman presents with a single, large, scaly, pink patch on her trunk (herald patch). One
week later, she develops multiple smaller, similar patches on her back and chest in a “Christmas tree”
distribution. The most likely diagnosis is:
• A) Tinea corporis
• B) Pityriasis rosea ✅
• C) Psoriasis
• D) Secondary syphilis
Rationale: The classic presentation of pityriasis rosea begins with a herald patch, followed days to weeks
later by a generalized rash in a Christmas tree pattern along the lines of skin tension. It is self-limited
and often follows a viral illness.
Question 7
A 6-year-old child presents with honey-colored crusted lesions on the face around the nose and mouth.
The lesions are mildly pruritic. The most likely diagnosis is:
• A) Atopic dermatitis
• B) Impetigo ✅
• C) Herpes simplex
• D) Contact dermatitis
Rationale: Honey-colored crusted lesions are the hallmark of impetigo, a superficial bacterial skin
infection commonly caused by Staphylococcus aureus or Streptococcus pyogenes. It is highly contagious.
Question 8
A 55-year-old man presents with a well-circumscribed, raised, erythematous plaque covered with
silvery-white scales on his elbows and knees. The most likely diagnosis is:
• A) Psoriasis ✅
• B) Eczema
• C) Pityriasis rosea
, 4
• D) Lichen planus
Rationale: The classic description of well-demarcated, erythematous plaques with silvery scales on
extensor surfaces (elbows, knees) is characteristic of psoriasis vulgaris.
❖ Module 3: Otolaryngology (ENT)
Question 9
A 32-year-old presents with acute onset of severe ear pain, hearing loss, and a sensation of fullness in
the ear. Otoscopy reveals a bulging, erythematous, non-mobile tympanic membrane with loss of
landmarks. Which is the most likely diagnosis?
• A) Otitis externa
• B) Acute otitis media (AOM) ✅
• C) Serous otitis media (OME)
• D) Mastoiditis
Rationale: AOM is an acute infection of the middle ear with signs of acute inflammation (bulging,
erythematous, immobile TM) and often fever and otalgia.
Question 10
A 65-year-old woman reports progressive, bilateral hearing loss over several years. She has difficulty
hearing conversations in noisy environments. Tuning fork tests reveal air conduction greater than bone
conduction bilaterally (Rinne positive), and the Weber test lateralizes to the ear with better hearing.
Which type of hearing loss is most consistent?
• A) Sensorineural hearing loss ✅
• B) Conductive hearing loss
• C) Mixed hearing loss
• D) Central hearing loss
Rationale: In sensorineural hearing loss, both air and bone conduction are reduced equally, so Rinne
remains positive (AC > BC). Weber lateralizes to the better ear. Conductive loss causes a negative Rinne
(BC > AC) and Weber lateralizes to the affected ear.
Question 11
Final Exam: NR 576/ NR576 (Latest 2026/ 2027 Update)
Differential Diagnosis in Adult-Gerontology Primary Care
Guide |Questions with Verified Answers| Grade A| 100%
Correct -Chamberlain.
Module 1: Foundations of Differential Diagnosis & Hematology
Question 1
A 72-year-old patient presents with fatigue, pallor, and dyspnea on exertion. Labs reveal macrocytic
anemia (MCV > 100 fL). Which additional lab finding would be most consistent with pernicious anemia?
• A) Low serum B12 with positive anti-intrinsic factor antibodies ✅
• B) Low serum folate with normal B12
• C) High ferritin with low TIBC
• D) Normal B12 with high methylmalonic acid
Rationale: Pernicious anemia is caused by B12 deficiency due to lack of intrinsic factor, leading to
macrocytic anemia. Anti-intrinsic factor antibodies are highly specific for pernicious anemia. While
elevated methylmalonic acid is also a marker for B12 deficiency, the question asks for the finding most
consistent with the diagnosis. Positive anti-intrinsic factor antibodies are the hallmark of pernicious
anemia.
Question 2
A 68-year-old woman with a history of chronic kidney disease presents with fatigue. Labs show
microcytic anemia (MCV 72 fL), low ferritin, and elevated TIBC. Which is the most likely diagnosis?
• A) Anemia of chronic disease
• B) Sideroblastic anemia
• C) Iron deficiency anemia ✅
• D) Thalassemia trait
Rationale: This pattern (low ferritin, high TIBC) is classic for iron deficiency anemia. Anemia of chronic
disease typically presents with normal or high ferritin and low TIBC.
,2
Question 3
A patient with a history of heavy alcohol use presents with macrocytic anemia. Which test is most useful
to differentiate B12 deficiency from folate deficiency?
• A) Methylmalonic acid (MMA) level ✅
• B) Homocysteine level
• C) Complete blood count (CBC)
• D) Peripheral smear
Rationale: Both B12 and folate deficiencies cause elevated homocysteine, but only B12 deficiency
causes elevated MMA. Measuring MMA is the best way to distinguish them.
Question 4
A 70-year-old man presents with unintentional weight loss, early satiety, and massive splenomegaly. His
CBC shows leukocytosis with a left shift and thrombocytosis. The most likely diagnosis is:
• A) Chronic lymphocytic leukemia (CLL)
• B) Chronic myeloid leukemia (CML) ✅
• C) Polycythemia vera (PV)
• D) Myelodysplastic syndrome (MDS)
Rationale: Massive splenomegaly, leukocytosis with a left shift, and thrombocytosis are classic for CML,
especially in older adults. The presence of the Philadelphia chromosome is diagnostic.
❖ Module 2: Dermatology
Question 5
A 45-year-old farmer presents with a rough, scaly, erythematous patch on his dorsal hand that has been
present for several months. It is not painful or pruritic. Which is the most likely diagnosis?
• A) Basal cell carcinoma
• B) Squamous cell carcinoma
• C) Actinic keratosis ✅
• D) Seborrheic keratosis
,3
Rationale: Actinic keratosis presents as a rough, scaly, erythematous patch on sun-exposed skin. It is
considered a precancerous lesion and may progress to squamous cell carcinoma. Seborrheic keratosis
has a “stuck-on” appearance.
Question 6
A 28-year-old woman presents with a single, large, scaly, pink patch on her trunk (herald patch). One
week later, she develops multiple smaller, similar patches on her back and chest in a “Christmas tree”
distribution. The most likely diagnosis is:
• A) Tinea corporis
• B) Pityriasis rosea ✅
• C) Psoriasis
• D) Secondary syphilis
Rationale: The classic presentation of pityriasis rosea begins with a herald patch, followed days to weeks
later by a generalized rash in a Christmas tree pattern along the lines of skin tension. It is self-limited
and often follows a viral illness.
Question 7
A 6-year-old child presents with honey-colored crusted lesions on the face around the nose and mouth.
The lesions are mildly pruritic. The most likely diagnosis is:
• A) Atopic dermatitis
• B) Impetigo ✅
• C) Herpes simplex
• D) Contact dermatitis
Rationale: Honey-colored crusted lesions are the hallmark of impetigo, a superficial bacterial skin
infection commonly caused by Staphylococcus aureus or Streptococcus pyogenes. It is highly contagious.
Question 8
A 55-year-old man presents with a well-circumscribed, raised, erythematous plaque covered with
silvery-white scales on his elbows and knees. The most likely diagnosis is:
• A) Psoriasis ✅
• B) Eczema
• C) Pityriasis rosea
, 4
• D) Lichen planus
Rationale: The classic description of well-demarcated, erythematous plaques with silvery scales on
extensor surfaces (elbows, knees) is characteristic of psoriasis vulgaris.
❖ Module 3: Otolaryngology (ENT)
Question 9
A 32-year-old presents with acute onset of severe ear pain, hearing loss, and a sensation of fullness in
the ear. Otoscopy reveals a bulging, erythematous, non-mobile tympanic membrane with loss of
landmarks. Which is the most likely diagnosis?
• A) Otitis externa
• B) Acute otitis media (AOM) ✅
• C) Serous otitis media (OME)
• D) Mastoiditis
Rationale: AOM is an acute infection of the middle ear with signs of acute inflammation (bulging,
erythematous, immobile TM) and often fever and otalgia.
Question 10
A 65-year-old woman reports progressive, bilateral hearing loss over several years. She has difficulty
hearing conversations in noisy environments. Tuning fork tests reveal air conduction greater than bone
conduction bilaterally (Rinne positive), and the Weber test lateralizes to the ear with better hearing.
Which type of hearing loss is most consistent?
• A) Sensorineural hearing loss ✅
• B) Conductive hearing loss
• C) Mixed hearing loss
• D) Central hearing loss
Rationale: In sensorineural hearing loss, both air and bone conduction are reduced equally, so Rinne
remains positive (AC > BC). Weber lateralizes to the better ear. Conductive loss causes a negative Rinne
(BC > AC) and Weber lateralizes to the affected ear.
Question 11
