COMSAE COMPREHENSIVE OSTEOPATHIC MEDICAL SELF-ASSESSMENT EXAMINATION – PHASE 1
QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM
UPDATE 2026/2027.
Core Domains:
Osteopathic Principles and Practices
Medical Ethics and Jurisprudence
Pathophysiology and Disease Processes
Pharmacology and Therapeutics
Clinical Presentation and Diagnosis
Patient Communication and Counseling
Preventive Medicine and Public Health
Research and Evidence-Based Medicine
Healthcare Systems and Quality Improvement
Introduction
This examination is designed to assess a medical student's foundational knowledge and clinical reasoning skills in
preparation for professional practice. It evaluates the application of core biomedical and clinical sciences,
osteopathic principles, and ethical standards to patient care scenarios. The assessment utilizes a multiple-choice
format, incorporating both straightforward knowledge recall and complex, scenario-based questions that challenge
,the test-taker to synthesize information and make sound clinical decisions. Emphasis is placed on the safe,
effective, and patient-centered application of medical knowledge, simulating real-world challenges encountered in
clinical settings and requiring astute clinical judgment and decision-making skills.
Section One: Questions 1–100
1. A 55-year-old male with a 30-pack-year smoking history presents with a chronic cough, hemoptysis, and
weight loss. A chest X-ray reveals a hilar mass. A biopsy confirms small cell lung cancer. Which of the
following paraneoplastic syndromes is most likely to be associated with this patient's malignancy?
A. Hypercalcemia
B. Syndrome of inappropriate antidiuretic hormone (SIADH)
C. Cushing's syndrome
D. Hypertrophic osteoarthropathy
🟢 B. Syndrome of inappropriate antidiuretic hormone (SIADH)
🔴 RATIONALE: Small cell lung cancer (SCLC) is a neuroendocrine tumor known for its association with
paraneoplastic syndromes, most commonly SIADH. The tumor produces ectopic antidiuretic hormone (ADH),
leading to water retention, hyponatremia, and concentrated urine. Hypercalcemia is more commonly associated
with squamous cell lung cancer. Cushing's syndrome, from ectopic ACTH, and hypertrophic osteoarthropathy
are also associated with lung cancer, particularly non-small cell types, but SIADH is the classic paraneoplastic
syndrome for SCLC.
,2. A 28-year-old female presents with fatigue, joint pain, and a characteristic malar rash. Laboratory results
show positive antinuclear antibodies (ANA) and anti-dsDNA antibodies. Which of the following is the most
likely diagnosis?
A. Rheumatoid arthritis
B. Systemic lupus erythematosus (SLE)
C. Scleroderma
D. Polymyositis
🟢 B. Systemic lupus erythematosus (SLE)
🔴 RATIONALE: The combination of a malar rash, fatigue, joint pain, and positive ANA and anti-dsDNA
antibodies is highly specific for Systemic Lupus Erythematosus (SLE). The malar rash is a hallmark cutaneous
manifestation of SLE. Rheumatoid arthritis primarily affects joints symmetrically and is associated with
rheumatoid factor, not anti-dsDNA. Scleroderma is characterized by skin thickening and Raynaud's
phenomenon, while Polymyositis presents with proximal muscle weakness.
3. A 65-year-old male with a history of hypertension and type 2 diabetes presents with sudden onset of
severe, tearing chest pain that radiates to his back. His blood pressure is 180/100 mmHg in the right arm and
140/80 mmHg in the left. Which of the following is the most likely initial diagnostic imaging study to confirm
the suspected diagnosis?
A. Chest X-ray
B. Transthoracic echocardiogram
C. CT angiography of the chest
D. Pulmonary angiography
, 🟢 C. CT angiography of the chest
🔴 RATIONALE: The patient is presenting with symptoms classic for an acute aortic dissection: sudden, severe,
tearing chest pain radiating to the back with a significant blood pressure differential between arms. CT
angiography of the chest is the most sensitive and specific initial imaging modality for diagnosing aortic
dissection, providing rapid, detailed visualization of the aorta and its branches. A chest X-ray may show a
widened mediastinum but is non-diagnostic. An echocardiogram can assess for pericardial effusion but is not
the primary diagnostic tool. Pulmonary angiography is used to diagnose pulmonary embolism, a different
condition.
4. A 45-year-old woman with a history of gallstones presents with sudden onset of severe right upper
quadrant pain, nausea, and vomiting. She is febrile and has a positive Murphy's sign. Laboratory tests reveal
leukocytosis and elevated bilirubin. What is the most appropriate next step in management?
A. Oral cholecystogram
B. Endoscopic retrograde cholangiopancreatography (ERCP)
C. Cholecystectomy
D. Administration of oral antibiotics
🟢 C. Cholecystectomy
🔴 RATIONALE: This patient's presentation is consistent with acute cholecystitis, characterized by severe right
upper quadrant pain, fever, nausea, and a positive Murphy's sign. The presence of gallstones and elevated
bilirubin suggests obstruction of the cystic duct. Definitive management for acute cholecystitis is a
cholecystectomy, preferably performed early during the admission. ERCP is reserved for cases of common bile
duct stones or cholangitis. Oral cholecystogram is not used in the acute setting. IV antibiotics are administered
preoperatively, but surgery is the definitive treatment.
QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM
UPDATE 2026/2027.
Core Domains:
Osteopathic Principles and Practices
Medical Ethics and Jurisprudence
Pathophysiology and Disease Processes
Pharmacology and Therapeutics
Clinical Presentation and Diagnosis
Patient Communication and Counseling
Preventive Medicine and Public Health
Research and Evidence-Based Medicine
Healthcare Systems and Quality Improvement
Introduction
This examination is designed to assess a medical student's foundational knowledge and clinical reasoning skills in
preparation for professional practice. It evaluates the application of core biomedical and clinical sciences,
osteopathic principles, and ethical standards to patient care scenarios. The assessment utilizes a multiple-choice
format, incorporating both straightforward knowledge recall and complex, scenario-based questions that challenge
,the test-taker to synthesize information and make sound clinical decisions. Emphasis is placed on the safe,
effective, and patient-centered application of medical knowledge, simulating real-world challenges encountered in
clinical settings and requiring astute clinical judgment and decision-making skills.
Section One: Questions 1–100
1. A 55-year-old male with a 30-pack-year smoking history presents with a chronic cough, hemoptysis, and
weight loss. A chest X-ray reveals a hilar mass. A biopsy confirms small cell lung cancer. Which of the
following paraneoplastic syndromes is most likely to be associated with this patient's malignancy?
A. Hypercalcemia
B. Syndrome of inappropriate antidiuretic hormone (SIADH)
C. Cushing's syndrome
D. Hypertrophic osteoarthropathy
🟢 B. Syndrome of inappropriate antidiuretic hormone (SIADH)
🔴 RATIONALE: Small cell lung cancer (SCLC) is a neuroendocrine tumor known for its association with
paraneoplastic syndromes, most commonly SIADH. The tumor produces ectopic antidiuretic hormone (ADH),
leading to water retention, hyponatremia, and concentrated urine. Hypercalcemia is more commonly associated
with squamous cell lung cancer. Cushing's syndrome, from ectopic ACTH, and hypertrophic osteoarthropathy
are also associated with lung cancer, particularly non-small cell types, but SIADH is the classic paraneoplastic
syndrome for SCLC.
,2. A 28-year-old female presents with fatigue, joint pain, and a characteristic malar rash. Laboratory results
show positive antinuclear antibodies (ANA) and anti-dsDNA antibodies. Which of the following is the most
likely diagnosis?
A. Rheumatoid arthritis
B. Systemic lupus erythematosus (SLE)
C. Scleroderma
D. Polymyositis
🟢 B. Systemic lupus erythematosus (SLE)
🔴 RATIONALE: The combination of a malar rash, fatigue, joint pain, and positive ANA and anti-dsDNA
antibodies is highly specific for Systemic Lupus Erythematosus (SLE). The malar rash is a hallmark cutaneous
manifestation of SLE. Rheumatoid arthritis primarily affects joints symmetrically and is associated with
rheumatoid factor, not anti-dsDNA. Scleroderma is characterized by skin thickening and Raynaud's
phenomenon, while Polymyositis presents with proximal muscle weakness.
3. A 65-year-old male with a history of hypertension and type 2 diabetes presents with sudden onset of
severe, tearing chest pain that radiates to his back. His blood pressure is 180/100 mmHg in the right arm and
140/80 mmHg in the left. Which of the following is the most likely initial diagnostic imaging study to confirm
the suspected diagnosis?
A. Chest X-ray
B. Transthoracic echocardiogram
C. CT angiography of the chest
D. Pulmonary angiography
, 🟢 C. CT angiography of the chest
🔴 RATIONALE: The patient is presenting with symptoms classic for an acute aortic dissection: sudden, severe,
tearing chest pain radiating to the back with a significant blood pressure differential between arms. CT
angiography of the chest is the most sensitive and specific initial imaging modality for diagnosing aortic
dissection, providing rapid, detailed visualization of the aorta and its branches. A chest X-ray may show a
widened mediastinum but is non-diagnostic. An echocardiogram can assess for pericardial effusion but is not
the primary diagnostic tool. Pulmonary angiography is used to diagnose pulmonary embolism, a different
condition.
4. A 45-year-old woman with a history of gallstones presents with sudden onset of severe right upper
quadrant pain, nausea, and vomiting. She is febrile and has a positive Murphy's sign. Laboratory tests reveal
leukocytosis and elevated bilirubin. What is the most appropriate next step in management?
A. Oral cholecystogram
B. Endoscopic retrograde cholangiopancreatography (ERCP)
C. Cholecystectomy
D. Administration of oral antibiotics
🟢 C. Cholecystectomy
🔴 RATIONALE: This patient's presentation is consistent with acute cholecystitis, characterized by severe right
upper quadrant pain, fever, nausea, and a positive Murphy's sign. The presence of gallstones and elevated
bilirubin suggests obstruction of the cystic duct. Definitive management for acute cholecystitis is a
cholecystectomy, preferably performed early during the admission. ERCP is reserved for cases of common bile
duct stones or cholangitis. Oral cholecystogram is not used in the acute setting. IV antibiotics are administered
preoperatively, but surgery is the definitive treatment.
