COMSAE PHASE 1 FORM 104 QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES
2026 Q&A |LATEST EXAM UPDATE 2026/2027.
Core Domains
Osteopathic Principles and Practice
Cardiovascular System
Pulmonary System
Gastrointestinal System
Neurology
Psychiatry and Behavioral Medicine
Musculoskeletal System
Pharmacology
Medical Ethics and Jurisprudence
Introduction
This comprehensive assessment is designed to evaluate a candidate's readiness for the COMSAE Phase 1
examination. It rigorously tests foundational biomedical knowledge, clinical reasoning skills, and the application of
osteopathic principles in patient care. The exam consists of multiple-choice questions, many of which are presented
in a clinical scenario-based format to simulate real-world medical decision-making. Emphasis is placed on the
integration of basic sciences with clinical practice, ethical standards, and the ability to synthesize information to
solve complex medical problems. This document serves as a definitive study resource, providing verified answers
and detailed rationales for each question.
SECTION ONE: QUESTIONS 1–100
,1. A 72-year-old male with a history of hypertension presents with sudden onset of severe, tearing chest pain
that radiates to his back. His blood pressure is 150/90 mmHg in the right arm and 100/70 mmHg in the left
arm. Which of the following is the most likely diagnosis?
A. Myocardial infarction
B. Pulmonary embolism
C. Aortic dissection
D. Pericarditis
🟢 C. Aortic dissection
🔴 RATIONALE: Aortic dissection classically presents with acute, severe, tearing chest pain that radiates to the
back. A key physical examination finding is a differential in blood pressure between the arms. While a
myocardial infarction (A) can cause chest pain, it is not typically tearing in nature nor associated with a blood
pressure differential. Pulmonary embolism (B) usually presents with pleuritic chest pain and dyspnea. Pericarditis
(D) presents with sharp, positional chest pain and a pericardial friction rub.
2. A 45-year-old female with a history of asthma is brought to the emergency department with shortness of
breath. She is using accessory muscles to breathe and has a prolonged expiratory phase. Which of the
following is the most appropriate initial pharmacologic intervention?
A. Oral prednisone
B. Inhaled albuterol
C. Inhaled ipratropium bromide
D. Intravenous magnesium sulfate
🟢 B. Inhaled albuterol
,🔴 RATIONALE: Inhaled albuterol (B) is a short-acting beta-2 agonist (SABA) and is the first-line treatment for
acute bronchospasm in asthma. It provides rapid bronchodilation. Oral prednisone (A) is a systemic
corticosteroid used for acute exacerbations but takes several hours to take effect, making it secondary to SABA.
Inhaled ipratropium (C) is an anticholinergic that can be added to SABA for severe exacerbations, but it is not
the initial monotherapy. Intravenous magnesium (D) is a third-line agent for refractory severe asthma.
3. A 28-year-old medical student is preparing for a board exam and experiences persistent, excessive worry
about his performance, difficulty sleeping, and muscle tension. These symptoms have been present for the
last eight months and are interfering with his daily activities. Which of the following is the most likely
diagnosis?
A. Major Depressive Disorder
B. Panic Disorder
C. Generalized Anxiety Disorder
D. Obsessive-Compulsive Disorder
🟢 C. Generalized Anxiety Disorder
🔴 RATIONALE: Generalized Anxiety Disorder (GAD) is characterized by excessive, uncontrollable worry
occurring more days than not for at least six months, accompanied by symptoms like restlessness, fatigue,
difficulty concentrating, irritability, muscle tension, and sleep disturbance. Major Depressive Disorder (A) has a
core symptom of depressed mood or anhedonia. Panic Disorder (B) is marked by recurrent, unexpected panic
attacks. Obsessive-Compulsive Disorder (D) involves obsessions and compulsions.
4. A 34-year-old female presents with joint pain, a malar rash, and photosensitivity. Laboratory results reveal
a positive antinuclear antibody (ANA) and anti-dsDNA antibodies. Which of the following is the most likely
cause of her renal complications?
, A. IgA nephropathy
B. Focal segmental glomerulosclerosis
C. Diffuse proliferative glomerulonephritis
D. Membranous nephropathy
🟢 C. Diffuse proliferative glomerulonephritis
🔴 RATIONALE: The patient's presentation of malar rash, photosensitivity, positive ANA, and anti-dsDNA
antibodies is classic for Systemic Lupus Erythematosus (SLE). The most common and severe form of lupus
nephritis is diffuse proliferative glomerulonephritis (Class IV), which is characterized by subendothelial immune
complex deposition and is associated with a poor prognosis if not treated. IgA nephropathy (A) is not typically
associated with SLE. Focal segmental glomerulosclerosis (B) is more commonly primary or secondary to
conditions like HIV or obesity. Membranous nephropathy (D) is associated with SLE (Class V) but is less common
than diffuse proliferative GN.
5. A 60-year-old male with a history of chronic alcohol use presents with confusion, nystagmus, and ataxia.
He is noted to have a broad-based gait and difficulty with tandem walking. Which of the following vitamin
deficiencies is most likely responsible for his neurologic symptoms?
A. Vitamin B12
B. Thiamine (Vitamin B1)
C. Niacin (Vitamin B3)
D. Vitamin E
🟢 B. Thiamine (Vitamin B1)
2026 Q&A |LATEST EXAM UPDATE 2026/2027.
Core Domains
Osteopathic Principles and Practice
Cardiovascular System
Pulmonary System
Gastrointestinal System
Neurology
Psychiatry and Behavioral Medicine
Musculoskeletal System
Pharmacology
Medical Ethics and Jurisprudence
Introduction
This comprehensive assessment is designed to evaluate a candidate's readiness for the COMSAE Phase 1
examination. It rigorously tests foundational biomedical knowledge, clinical reasoning skills, and the application of
osteopathic principles in patient care. The exam consists of multiple-choice questions, many of which are presented
in a clinical scenario-based format to simulate real-world medical decision-making. Emphasis is placed on the
integration of basic sciences with clinical practice, ethical standards, and the ability to synthesize information to
solve complex medical problems. This document serves as a definitive study resource, providing verified answers
and detailed rationales for each question.
SECTION ONE: QUESTIONS 1–100
,1. A 72-year-old male with a history of hypertension presents with sudden onset of severe, tearing chest pain
that radiates to his back. His blood pressure is 150/90 mmHg in the right arm and 100/70 mmHg in the left
arm. Which of the following is the most likely diagnosis?
A. Myocardial infarction
B. Pulmonary embolism
C. Aortic dissection
D. Pericarditis
🟢 C. Aortic dissection
🔴 RATIONALE: Aortic dissection classically presents with acute, severe, tearing chest pain that radiates to the
back. A key physical examination finding is a differential in blood pressure between the arms. While a
myocardial infarction (A) can cause chest pain, it is not typically tearing in nature nor associated with a blood
pressure differential. Pulmonary embolism (B) usually presents with pleuritic chest pain and dyspnea. Pericarditis
(D) presents with sharp, positional chest pain and a pericardial friction rub.
2. A 45-year-old female with a history of asthma is brought to the emergency department with shortness of
breath. She is using accessory muscles to breathe and has a prolonged expiratory phase. Which of the
following is the most appropriate initial pharmacologic intervention?
A. Oral prednisone
B. Inhaled albuterol
C. Inhaled ipratropium bromide
D. Intravenous magnesium sulfate
🟢 B. Inhaled albuterol
,🔴 RATIONALE: Inhaled albuterol (B) is a short-acting beta-2 agonist (SABA) and is the first-line treatment for
acute bronchospasm in asthma. It provides rapid bronchodilation. Oral prednisone (A) is a systemic
corticosteroid used for acute exacerbations but takes several hours to take effect, making it secondary to SABA.
Inhaled ipratropium (C) is an anticholinergic that can be added to SABA for severe exacerbations, but it is not
the initial monotherapy. Intravenous magnesium (D) is a third-line agent for refractory severe asthma.
3. A 28-year-old medical student is preparing for a board exam and experiences persistent, excessive worry
about his performance, difficulty sleeping, and muscle tension. These symptoms have been present for the
last eight months and are interfering with his daily activities. Which of the following is the most likely
diagnosis?
A. Major Depressive Disorder
B. Panic Disorder
C. Generalized Anxiety Disorder
D. Obsessive-Compulsive Disorder
🟢 C. Generalized Anxiety Disorder
🔴 RATIONALE: Generalized Anxiety Disorder (GAD) is characterized by excessive, uncontrollable worry
occurring more days than not for at least six months, accompanied by symptoms like restlessness, fatigue,
difficulty concentrating, irritability, muscle tension, and sleep disturbance. Major Depressive Disorder (A) has a
core symptom of depressed mood or anhedonia. Panic Disorder (B) is marked by recurrent, unexpected panic
attacks. Obsessive-Compulsive Disorder (D) involves obsessions and compulsions.
4. A 34-year-old female presents with joint pain, a malar rash, and photosensitivity. Laboratory results reveal
a positive antinuclear antibody (ANA) and anti-dsDNA antibodies. Which of the following is the most likely
cause of her renal complications?
, A. IgA nephropathy
B. Focal segmental glomerulosclerosis
C. Diffuse proliferative glomerulonephritis
D. Membranous nephropathy
🟢 C. Diffuse proliferative glomerulonephritis
🔴 RATIONALE: The patient's presentation of malar rash, photosensitivity, positive ANA, and anti-dsDNA
antibodies is classic for Systemic Lupus Erythematosus (SLE). The most common and severe form of lupus
nephritis is diffuse proliferative glomerulonephritis (Class IV), which is characterized by subendothelial immune
complex deposition and is associated with a poor prognosis if not treated. IgA nephropathy (A) is not typically
associated with SLE. Focal segmental glomerulosclerosis (B) is more commonly primary or secondary to
conditions like HIV or obesity. Membranous nephropathy (D) is associated with SLE (Class V) but is less common
than diffuse proliferative GN.
5. A 60-year-old male with a history of chronic alcohol use presents with confusion, nystagmus, and ataxia.
He is noted to have a broad-based gait and difficulty with tandem walking. Which of the following vitamin
deficiencies is most likely responsible for his neurologic symptoms?
A. Vitamin B12
B. Thiamine (Vitamin B1)
C. Niacin (Vitamin B3)
D. Vitamin E
🟢 B. Thiamine (Vitamin B1)