COMSAE Phase 1 Exam
2026 Edition Questions
with Verified Answers
and Detailed
Rationales
Question 1
A 64-year-old man with hypertension and hyperlipidemia
develops sudden right-sided weakness and expressive aphasia.
Symptoms began 90 minutes ago. CT of the head shows no
hemorrhage. Which treatment is most appropriate?
A. Aspirin only
B. Intravenous alteplase
,C. Intravenous heparin
D. Carotid endarterectomy
Answer: B. Intravenous alteplase
The patient has an acute ischemic stroke within the therapeutic
window for intravenous thrombolysis, with no evidence of
intracranial hemorrhage on CT. Alteplase is appropriate when
eligibility criteria are satisfied.
Question 2
A 23-year-old woman presents with fatigue, weight loss, heat
intolerance, tremor, and palpitations. Examination reveals a
diffuse goiter and bilateral exophthalmos. Which antibody is
most likely responsible?
A. Anti-thyroid peroxidase antibody
B. Anti-thyroglobulin antibody
C. Thyroid-stimulating immunoglobulin
D. Anti-centromere antibody
Answer: C. Thyroid-stimulating immunoglobulin
Graves disease is caused by thyroid-stimulating
immunoglobulins that activate the TSH receptor, producing
excess thyroid hormone and diffuse thyroid enlargement.
Orbital fibroblast activation contributes to ophthalmopathy.
,Question 3
A 58-year-old man develops crushing substernal chest pain
radiating to his left arm. ECG demonstrates ST-segment
elevation in leads II, III, and aVF. Which coronary artery is most
likely occluded?
A. Left anterior descending artery
B. Left circumflex artery
C. Right coronary artery
D. Left main coronary artery
Answer: C. Right coronary artery
Inferior-wall myocardial infarction is classically associated with
occlusion of the right coronary artery, although the left
circumflex artery can occasionally produce the same pattern.
Question 4
A 7-year-old child presents with periorbital edema and cola-
colored urine two weeks after recovering from impetigo.
Urinalysis reveals red blood cell casts. Which finding is most
likely?
A. Increased serum complement C3
B. Decreased serum complement C3
, C. Increased serum IgA
D. Positive anti-GBM antibodies
Answer: B. Decreased serum complement C3
Poststreptococcal glomerulonephritis is an immune complex–
mediated disease that commonly produces transient
hypocomplementemia, particularly decreased C3.
Question 5
A 42-year-old woman has recurrent episodes of severe
unilateral headaches associated with lacrimation and nasal
congestion. Each episode lasts approximately 90 minutes and
occurs several times per week. What is the most likely
diagnosis?
A. Migraine with aura
B. Cluster headache
C. Tension headache
D. Trigeminal neuralgia
Answer: B. Cluster headache
Cluster headaches cause severe unilateral orbital or temporal
pain accompanied by autonomic symptoms such as lacrimation
and rhinorrhea. Attacks typically occur in clusters over weeks to
months.
2026 Edition Questions
with Verified Answers
and Detailed
Rationales
Question 1
A 64-year-old man with hypertension and hyperlipidemia
develops sudden right-sided weakness and expressive aphasia.
Symptoms began 90 minutes ago. CT of the head shows no
hemorrhage. Which treatment is most appropriate?
A. Aspirin only
B. Intravenous alteplase
,C. Intravenous heparin
D. Carotid endarterectomy
Answer: B. Intravenous alteplase
The patient has an acute ischemic stroke within the therapeutic
window for intravenous thrombolysis, with no evidence of
intracranial hemorrhage on CT. Alteplase is appropriate when
eligibility criteria are satisfied.
Question 2
A 23-year-old woman presents with fatigue, weight loss, heat
intolerance, tremor, and palpitations. Examination reveals a
diffuse goiter and bilateral exophthalmos. Which antibody is
most likely responsible?
A. Anti-thyroid peroxidase antibody
B. Anti-thyroglobulin antibody
C. Thyroid-stimulating immunoglobulin
D. Anti-centromere antibody
Answer: C. Thyroid-stimulating immunoglobulin
Graves disease is caused by thyroid-stimulating
immunoglobulins that activate the TSH receptor, producing
excess thyroid hormone and diffuse thyroid enlargement.
Orbital fibroblast activation contributes to ophthalmopathy.
,Question 3
A 58-year-old man develops crushing substernal chest pain
radiating to his left arm. ECG demonstrates ST-segment
elevation in leads II, III, and aVF. Which coronary artery is most
likely occluded?
A. Left anterior descending artery
B. Left circumflex artery
C. Right coronary artery
D. Left main coronary artery
Answer: C. Right coronary artery
Inferior-wall myocardial infarction is classically associated with
occlusion of the right coronary artery, although the left
circumflex artery can occasionally produce the same pattern.
Question 4
A 7-year-old child presents with periorbital edema and cola-
colored urine two weeks after recovering from impetigo.
Urinalysis reveals red blood cell casts. Which finding is most
likely?
A. Increased serum complement C3
B. Decreased serum complement C3
, C. Increased serum IgA
D. Positive anti-GBM antibodies
Answer: B. Decreased serum complement C3
Poststreptococcal glomerulonephritis is an immune complex–
mediated disease that commonly produces transient
hypocomplementemia, particularly decreased C3.
Question 5
A 42-year-old woman has recurrent episodes of severe
unilateral headaches associated with lacrimation and nasal
congestion. Each episode lasts approximately 90 minutes and
occurs several times per week. What is the most likely
diagnosis?
A. Migraine with aura
B. Cluster headache
C. Tension headache
D. Trigeminal neuralgia
Answer: B. Cluster headache
Cluster headaches cause severe unilateral orbital or temporal
pain accompanied by autonomic symptoms such as lacrimation
and rhinorrhea. Attacks typically occur in clusters over weeks to
months.
