COMSAE 107: Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026/2027 Q&A | Instant Download Pdf
1. A 65-year-old man with a 40-pack-year smoking history presents with
progressive hoarseness and difficulty swallowing. Imaging reveals a tumor at
the lung apex eroding through the costal pleura. Which nerve is most likely
compressed?
A) Vagus nerve (CN X)
B) Recurrent laryngeal nerve
C) Phrenic nerve
D) Spinal accessory nerve
Answer B: Recurrent laryngeal nerve
Rationale: A Pancoast tumor at the lung apex can invade the sympathetic chain
(causing Horner syndrome) and the recurrent laryngeal nerve (causing hoarseness
due to vocal cord paralysis) .
2. A patient is diagnosed with pheochromocytoma. Which embryologic
derivative gives rise to this tumor?
A) Mesoderm
B) Neural crest
C) Endoderm
,D) Surface ectoderm
Answer B: Neural crest
Rationale: Chromaffin cells of the adrenal medulla, which give rise to
pheochromocytoma, are derived from neural crest cells .
3. A 70-year-old woman with progressive memory loss has diffuse cortical
atrophy, particularly in the hippocampus. Microscopy reveals neurofibrillary
tangles. Which protein is implicated?
A) α-synuclein
B) Tau protein
C) Huntingtin
D) Prion protein
Answer B: Tau protein
Rationale: Alzheimer disease is characterized by neurofibrillary tangles composed
of hyperphosphorylated tau protein .
4. A patient with rheumatoid arthritis is undergoing surgery. Which cervical
spine complication must be evaluated before intubation?
A) Spinal stenosis
B) Atlantoaxial subluxation
C) Herniated disc
D) Osteophyte formation
Answer B: Atlantoaxial subluxation
,Rationale: Rheumatoid arthritis can cause atlantoaxial instability, which poses a
risk of cord compression during intubation .
5. A patient has hemolytic anemia with a positive Coombs test. What is the
mechanism?
A) Type I hypersensitivity
B) Type II hypersensitivity
C) Type III hypersensitivity
D) Type IV hypersensitivity
Answer B: Type II hypersensitivity
Rationale: Autoimmune hemolytic anemia is a Type II hypersensitivity reaction
mediated by antibodies against red blood cell antigens .
6. A 32-year-old man has polyuria, polydipsia, hypernatremia, and dilute
urine after a head injury. Which is the most likely diagnosis?
A) SIADH
B) Central diabetes insipidus
C) Nephrogenic diabetes insipidus
D) Primary polydipsia
Answer B: Central diabetes insipidus
Rationale: Head trauma can cause central diabetes insipidus due to decreased
ADH secretion, leading to polyuria and dilute urine .
, 7. A 3-year-old boy has recurrent infections and an absent thymic shadow on
chest X-ray. What syndrome is this?
A) Wiskott-Aldrich syndrome
B) Chronic granulomatous disease
C) DiGeorge syndrome
D) Ataxia-telangiectasia
Answer C: DiGeorge syndrome
Rationale: DiGeorge syndrome (22q11 deletion) causes thymic aplasia, leading to
recurrent infections due to T-cell deficiency .
8. Which hepatitis viruses currently have vaccines available?
A) Hepatitis A and B
B) Hepatitis C and D
C) Hepatitis A and C
D) Hepatitis B and E
Answer A: Hepatitis A and B
Rationale: Vaccines are available for hepatitis A and B, and by virtue of the
hepatitis B vaccine, hepatitis D is also prevented .
9. A patient has a myocardial infarction involving the anterior wall. Which
artery is most likely occluded?
A) Right coronary artery
Answers (Verified Answers) Plus Rationales
2026/2027 Q&A | Instant Download Pdf
1. A 65-year-old man with a 40-pack-year smoking history presents with
progressive hoarseness and difficulty swallowing. Imaging reveals a tumor at
the lung apex eroding through the costal pleura. Which nerve is most likely
compressed?
A) Vagus nerve (CN X)
B) Recurrent laryngeal nerve
C) Phrenic nerve
D) Spinal accessory nerve
Answer B: Recurrent laryngeal nerve
Rationale: A Pancoast tumor at the lung apex can invade the sympathetic chain
(causing Horner syndrome) and the recurrent laryngeal nerve (causing hoarseness
due to vocal cord paralysis) .
2. A patient is diagnosed with pheochromocytoma. Which embryologic
derivative gives rise to this tumor?
A) Mesoderm
B) Neural crest
C) Endoderm
,D) Surface ectoderm
Answer B: Neural crest
Rationale: Chromaffin cells of the adrenal medulla, which give rise to
pheochromocytoma, are derived from neural crest cells .
3. A 70-year-old woman with progressive memory loss has diffuse cortical
atrophy, particularly in the hippocampus. Microscopy reveals neurofibrillary
tangles. Which protein is implicated?
A) α-synuclein
B) Tau protein
C) Huntingtin
D) Prion protein
Answer B: Tau protein
Rationale: Alzheimer disease is characterized by neurofibrillary tangles composed
of hyperphosphorylated tau protein .
4. A patient with rheumatoid arthritis is undergoing surgery. Which cervical
spine complication must be evaluated before intubation?
A) Spinal stenosis
B) Atlantoaxial subluxation
C) Herniated disc
D) Osteophyte formation
Answer B: Atlantoaxial subluxation
,Rationale: Rheumatoid arthritis can cause atlantoaxial instability, which poses a
risk of cord compression during intubation .
5. A patient has hemolytic anemia with a positive Coombs test. What is the
mechanism?
A) Type I hypersensitivity
B) Type II hypersensitivity
C) Type III hypersensitivity
D) Type IV hypersensitivity
Answer B: Type II hypersensitivity
Rationale: Autoimmune hemolytic anemia is a Type II hypersensitivity reaction
mediated by antibodies against red blood cell antigens .
6. A 32-year-old man has polyuria, polydipsia, hypernatremia, and dilute
urine after a head injury. Which is the most likely diagnosis?
A) SIADH
B) Central diabetes insipidus
C) Nephrogenic diabetes insipidus
D) Primary polydipsia
Answer B: Central diabetes insipidus
Rationale: Head trauma can cause central diabetes insipidus due to decreased
ADH secretion, leading to polyuria and dilute urine .
, 7. A 3-year-old boy has recurrent infections and an absent thymic shadow on
chest X-ray. What syndrome is this?
A) Wiskott-Aldrich syndrome
B) Chronic granulomatous disease
C) DiGeorge syndrome
D) Ataxia-telangiectasia
Answer C: DiGeorge syndrome
Rationale: DiGeorge syndrome (22q11 deletion) causes thymic aplasia, leading to
recurrent infections due to T-cell deficiency .
8. Which hepatitis viruses currently have vaccines available?
A) Hepatitis A and B
B) Hepatitis C and D
C) Hepatitis A and C
D) Hepatitis B and E
Answer A: Hepatitis A and B
Rationale: Vaccines are available for hepatitis A and B, and by virtue of the
hepatitis B vaccine, hepatitis D is also prevented .
9. A patient has a myocardial infarction involving the anterior wall. Which
artery is most likely occluded?
A) Right coronary artery
