COMSAE Phase 2 BSA Form 113i – Comprehensive
Exam with Questions, Answers and Rationales
2026/2027 Update
Question 1: Surgery / Vascular
A 67-year-old man presents with sudden onset of severe abdominal pain that is disproportionate
to physical examination findings. He has a history of atrial fibrillation and has not been
compliant with anticoagulation therapy. Laboratory studies reveal elevated serum lactate.
Which artery is most likely occluded?
A. Inferior mesenteric artery
B. Celiac trunk
C. Superior mesenteric artery
D. Internal iliac artery
Correct Answer: C. Superior mesenteric artery
Rationale:
Acute mesenteric ischemia classically presents with severe pain out of proportion to physical
examination findings. The superior mesenteric artery (SMA) is the vessel most commonly
affected by emboli originating from cardiac sources such as atrial fibrillation due to its narrow
takeoff angle. Elevated serum lactate reflects advanced tissue hypoxia and bowel infarction.
Question 2: Hematology
A 24-year-old woman presents with fatigue, pallor, and jaundice. Laboratory studies show
elevated LDH, low haptoglobin, and a positive direct Coombs test.
What is the most likely diagnosis?
A. Hereditary spherocytosis
B. G6PD deficiency
C. Microangiopathic hemolytic anemia
, D. Autoimmune hemolytic anemia
Correct Answer: D. Autoimmune hemolytic anemia
Rationale:
A positive direct Coombs (antiglobulin) test is the hallmark of autoimmune hemolytic anemia,
confirming antibody or complement binding to red blood cell membranes. Elevated lactate
dehydrogenase (LDH), decreased haptoglobin, and indirect hyperbilirubinemia are classic
laboratory features of intravascular and extravascular hemolysis.
Question 3: Infectious Disease
A patient develops fever, hypotension, and diffuse erythroderma two days after undergoing nasal
surgery with packing.
Which organism is most likely responsible?
A. Streptococcus pneumoniae
B. Pseudomonas aeruginosa
C. Staphylococcus aureus
D. Haemophilus influenzae
Correct Answer: C. Staphylococcus aureus
Rationale:
Toxic shock syndrome is caused by staphylococcal toxic shock syndrome toxin-1 (TSST-1) or
related exotoxins acting as superantigens. This triggers massive, non-specific T-cell activation
and cytokine release, leading to high fever, diffuse macular erythroderma, multi-organ
dysfunction, and profound shock. Prolonged nasal packing is a classic historical risk factor.
Question 4: Neurology
A 68-year-old man develops sudden right-sided weakness and aphasia. A non-contrast computed
tomography (CT) scan of the head shows no intracranial hemorrhage. Symptoms began 90
minutes ago.
What is the most appropriate next step in management?
A. Aspirin therapy only
B. Immediate carotid endarterectomy
, C. Administer intravenous thrombolytic therapy if eligible
D. Observation for 24 hours
Correct Answer: C. Administer intravenous thrombolytic therapy if eligible
Rationale:
Acute ischemic stroke presenting within the standard therapeutic window (typically up to 4.5
hours from symptom onset) without absolute contraindications (such as active bleeding or recent
surgery) should be treated promptly with intravenous recombinant tissue plasminogen activator
(alteplase) or tenecteplase to restore cerebral perfusion and limit permanent neurological
disability.
Question 5: Cardiology
A patient presenting with acute chest pain undergoes a 12-lead electrocardiogram that
demonstrates significant ST-segment elevations in leads II, III, and aVF.
Which coronary artery is most likely involved?
A. Left anterior descending artery
B. Circumflex artery
C. Right coronary artery
D. Left main coronary artery
Correct Answer: C. Right coronary artery
Rationale:
Inferior wall myocardial infarctions characteristically manifest with ST-segment elevations in
inferior leads II, III, and aVF. In the majority of individuals, the right coronary artery supplies
the inferior wall of the left ventricle as well as the sinoatrial and atrioventricular nodes.
Question 6: Nephrology / Electrolytes
A patient with chronic kidney disease presents to the emergency department complaining of
generalized muscle weakness and palpitations. An electrocardiogram reveals tall, peaked T
waves, a prolonged PR interval, and widened QRS complexes.
What is the underlying electrolyte disturbance?
A. Hypocalcemia
, B. Hyponatremia
C. Hyperkalemia
D. Hypokalemia
Correct Answer: C. Hyperkalemia
Rationale:
Severe hyperkalemia alters resting membrane potentials, leading to classic electrocardiographic
changes progressing sequentially from tall peaked T waves and shortened QT intervals to PR
prolongation, widened QRS complexes, loss of P waves, and ultimately sine waves or ventricular
fibrillation if left untreated.
Question 7: Pulmonology
A 62-year-old man with a 40-pack-year smoking history presents with worsening dyspnea, a
chronic productive cough, and a barrel-shaped chest. Spirometry demonstrates a forced
expiratory volume in 1 second to forced vital capacity ratio ($FEV_1/FVC$) of 0.60 that shows
minimal reversibility after bronchodilator administration.
What is the primary physiological mechanism responsible for airflow limitation in this
condition?
A. Loss of elastic recoil and destruction of alveolar walls
B. Immediate IgE-mediated bronchoconstriction of smooth muscle
C. Fixed granulomatous obstruction of central airways
D. Pulmonary capillary bed obliteration without parenchymal damage
Correct Answer: A. Loss of elastic recoil and destruction of alveolar walls
Rationale:
Chronic obstructive pulmonary disease (COPD), specifically emphysema, involves permanent
destruction of alveolar walls and loss of radial traction on small airways. This loss of elastic
recoil causes premature expiratory airway collapse, air trapping, and irreversible airflow
limitation.
Question 8: Endocrinology
Exam with Questions, Answers and Rationales
2026/2027 Update
Question 1: Surgery / Vascular
A 67-year-old man presents with sudden onset of severe abdominal pain that is disproportionate
to physical examination findings. He has a history of atrial fibrillation and has not been
compliant with anticoagulation therapy. Laboratory studies reveal elevated serum lactate.
Which artery is most likely occluded?
A. Inferior mesenteric artery
B. Celiac trunk
C. Superior mesenteric artery
D. Internal iliac artery
Correct Answer: C. Superior mesenteric artery
Rationale:
Acute mesenteric ischemia classically presents with severe pain out of proportion to physical
examination findings. The superior mesenteric artery (SMA) is the vessel most commonly
affected by emboli originating from cardiac sources such as atrial fibrillation due to its narrow
takeoff angle. Elevated serum lactate reflects advanced tissue hypoxia and bowel infarction.
Question 2: Hematology
A 24-year-old woman presents with fatigue, pallor, and jaundice. Laboratory studies show
elevated LDH, low haptoglobin, and a positive direct Coombs test.
What is the most likely diagnosis?
A. Hereditary spherocytosis
B. G6PD deficiency
C. Microangiopathic hemolytic anemia
, D. Autoimmune hemolytic anemia
Correct Answer: D. Autoimmune hemolytic anemia
Rationale:
A positive direct Coombs (antiglobulin) test is the hallmark of autoimmune hemolytic anemia,
confirming antibody or complement binding to red blood cell membranes. Elevated lactate
dehydrogenase (LDH), decreased haptoglobin, and indirect hyperbilirubinemia are classic
laboratory features of intravascular and extravascular hemolysis.
Question 3: Infectious Disease
A patient develops fever, hypotension, and diffuse erythroderma two days after undergoing nasal
surgery with packing.
Which organism is most likely responsible?
A. Streptococcus pneumoniae
B. Pseudomonas aeruginosa
C. Staphylococcus aureus
D. Haemophilus influenzae
Correct Answer: C. Staphylococcus aureus
Rationale:
Toxic shock syndrome is caused by staphylococcal toxic shock syndrome toxin-1 (TSST-1) or
related exotoxins acting as superantigens. This triggers massive, non-specific T-cell activation
and cytokine release, leading to high fever, diffuse macular erythroderma, multi-organ
dysfunction, and profound shock. Prolonged nasal packing is a classic historical risk factor.
Question 4: Neurology
A 68-year-old man develops sudden right-sided weakness and aphasia. A non-contrast computed
tomography (CT) scan of the head shows no intracranial hemorrhage. Symptoms began 90
minutes ago.
What is the most appropriate next step in management?
A. Aspirin therapy only
B. Immediate carotid endarterectomy
, C. Administer intravenous thrombolytic therapy if eligible
D. Observation for 24 hours
Correct Answer: C. Administer intravenous thrombolytic therapy if eligible
Rationale:
Acute ischemic stroke presenting within the standard therapeutic window (typically up to 4.5
hours from symptom onset) without absolute contraindications (such as active bleeding or recent
surgery) should be treated promptly with intravenous recombinant tissue plasminogen activator
(alteplase) or tenecteplase to restore cerebral perfusion and limit permanent neurological
disability.
Question 5: Cardiology
A patient presenting with acute chest pain undergoes a 12-lead electrocardiogram that
demonstrates significant ST-segment elevations in leads II, III, and aVF.
Which coronary artery is most likely involved?
A. Left anterior descending artery
B. Circumflex artery
C. Right coronary artery
D. Left main coronary artery
Correct Answer: C. Right coronary artery
Rationale:
Inferior wall myocardial infarctions characteristically manifest with ST-segment elevations in
inferior leads II, III, and aVF. In the majority of individuals, the right coronary artery supplies
the inferior wall of the left ventricle as well as the sinoatrial and atrioventricular nodes.
Question 6: Nephrology / Electrolytes
A patient with chronic kidney disease presents to the emergency department complaining of
generalized muscle weakness and palpitations. An electrocardiogram reveals tall, peaked T
waves, a prolonged PR interval, and widened QRS complexes.
What is the underlying electrolyte disturbance?
A. Hypocalcemia
, B. Hyponatremia
C. Hyperkalemia
D. Hypokalemia
Correct Answer: C. Hyperkalemia
Rationale:
Severe hyperkalemia alters resting membrane potentials, leading to classic electrocardiographic
changes progressing sequentially from tall peaked T waves and shortened QT intervals to PR
prolongation, widened QRS complexes, loss of P waves, and ultimately sine waves or ventricular
fibrillation if left untreated.
Question 7: Pulmonology
A 62-year-old man with a 40-pack-year smoking history presents with worsening dyspnea, a
chronic productive cough, and a barrel-shaped chest. Spirometry demonstrates a forced
expiratory volume in 1 second to forced vital capacity ratio ($FEV_1/FVC$) of 0.60 that shows
minimal reversibility after bronchodilator administration.
What is the primary physiological mechanism responsible for airflow limitation in this
condition?
A. Loss of elastic recoil and destruction of alveolar walls
B. Immediate IgE-mediated bronchoconstriction of smooth muscle
C. Fixed granulomatous obstruction of central airways
D. Pulmonary capillary bed obliteration without parenchymal damage
Correct Answer: A. Loss of elastic recoil and destruction of alveolar walls
Rationale:
Chronic obstructive pulmonary disease (COPD), specifically emphysema, involves permanent
destruction of alveolar walls and loss of radial traction on small airways. This loss of elastic
recoil causes premature expiratory airway collapse, air trapping, and irreversible airflow
limitation.
Question 8: Endocrinology
