COMSAE PHASE 1 FORM 115 QUESTIONS AND
CORRECT ANSWERS (VERIFIED ANSWERS) PLUS
RATIONALES 2026/2027 Q&A | INSTANT
DOWNLOAD PDF.
Core Domains
• Behavioral Science
• Biochemistry
• Microbiology
• Immunology
• Pathology
• Pharmacology
• Physiology
• Public Health
Introduction
The COMSAE Phase 1 Form 115 examination evaluates foundational biomedical knowledge and clinical
reasoning skills essential for osteopathic medical students. It assesses comprehension of basic sciences,
systems-based pathophysiology, and principles of patient care. The assessment utilizes multiple-choice
and scenario-based questions to simulate real-world clinical decision-making. Emphasis is placed on
application of knowledge, integration of concepts, and adherence to ethical and professional standards.
This practice tool provides comprehensive preparation to identify strengths and areas requiring further
study, ensuring readiness for licensure examinations and clinical rotations. It promotes critical thinking
and evidence-based practice across all core domains.
Section One: Questions 1–100
Question 1
A 24-year-old male presents with fever, sore throat, and fatigue. Physical examination reveals
splenomegaly and posterior cervical lymphadenopathy. A heterophile antibody test is positive. Which of
the following complications is most likely associated with this condition?
A. Aplastic anemia
B. Hemolytic uremic syndrome
C. Splenic rupture
D. Rheumatic fever
, Correct answer
C. Splenic rupture
RATIONALE: Infectious mononucleosis caused by Epstein-Barr virus can lead to splenomegaly, which
predisposes to splenic rupture, especially with contact sports or trauma.
Question 2
A 60-year-old male with a history of chronic alcohol abuse presents with confusion, ataxia, and
ophthalmoplegia. Which vitamin deficiency is most likely responsible for these symptoms?
A. Vitamin B12
B. Vitamin C
C. Vitamin B6
D. Vitamin B1
Correct answer
D. Vitamin B1
RATIONALE: Thiamine deficiency in chronic alcohol abuse leads to Wernicke encephalopathy,
characterized by confusion, ataxia, and ophthalmoplegia.
Question 3
A 36-year-old female presents with a malar rash, photosensitivity, and oral ulcers. Which autoantibody
is most specific for her likely diagnosis?
A. Anti-histone
B. Anti-Scl-70
C. Anti-dsDNA
D. Rheumatoid factor
Correct answer
C. Anti-dsDNA
RATIONALE: Anti-double-stranded DNA antibodies are highly specific for systemic lupus
erythematosus, which presents with malar rash, photosensitivity, and oral ulcers.
Question 4
A 64-year-old male presents with progressive dysphagia for solids and weight loss. Which of the
following is the most likely diagnosis?
A. Achalasia
B. Gastroesophageal reflux disease
C. Esophageal stricture
D. Esophageal carcinoma
Correct answer
D. Esophageal carcinoma
RATIONALE: Progressive dysphagia for solids and weight loss in an older male is concerning for
esophageal carcinoma, often associated with smoking and alcohol use.
, Question 5
A 30-year-old female presents with recurrent pregnancy loss. Which of the following is the most likely
underlying cause?
A. Factor V Leiden mutation
B. Protein C deficiency
C. Antiphospholipid syndrome
D. Systemic lupus erythematosus
Correct answer
C. Antiphospholipid syndrome
RATIONALE: Antiphospholipid syndrome is associated with recurrent arterial and venous
thrombosis, including recurrent pregnancy loss.
Question 6
A 47-year-old male presents with severe chest pain and is diagnosed with an acute myocardial
infarction. Which laboratory finding is most specific for myocardial injury?
A. Elevated lactate dehydrogenase
B. Elevated creatine kinase-MB
C. Elevated troponin I
D. Elevated aspartate aminotransferase
Correct answer
C. Elevated troponin I
RATIONALE: Troponin I is highly specific to cardiac muscle and is the preferred biomarker for
diagnosing myocardial infarction.
Question 7
A 32-year-old female is prescribed a drug that inhibits cyclooxygenase. Which therapeutic effect is most
directly attributed to this mechanism?
A. Enhanced gastric mucosal protection
B. Reduced fever and inflammation
C. Increased blood clotting
D. Bronchodilation
Correct answer
B. Reduced fever and inflammation
RATIONALE: Cyclooxygenase inhibition decreases prostaglandin synthesis, which reduces fever, pain,
and inflammation.
Question 8
A 69-year-old female presents with bone pain and hypercalcemia. Which underlying malignancy is most
likely?
A. Breast cancer
B. Lung cancer
CORRECT ANSWERS (VERIFIED ANSWERS) PLUS
RATIONALES 2026/2027 Q&A | INSTANT
DOWNLOAD PDF.
Core Domains
• Behavioral Science
• Biochemistry
• Microbiology
• Immunology
• Pathology
• Pharmacology
• Physiology
• Public Health
Introduction
The COMSAE Phase 1 Form 115 examination evaluates foundational biomedical knowledge and clinical
reasoning skills essential for osteopathic medical students. It assesses comprehension of basic sciences,
systems-based pathophysiology, and principles of patient care. The assessment utilizes multiple-choice
and scenario-based questions to simulate real-world clinical decision-making. Emphasis is placed on
application of knowledge, integration of concepts, and adherence to ethical and professional standards.
This practice tool provides comprehensive preparation to identify strengths and areas requiring further
study, ensuring readiness for licensure examinations and clinical rotations. It promotes critical thinking
and evidence-based practice across all core domains.
Section One: Questions 1–100
Question 1
A 24-year-old male presents with fever, sore throat, and fatigue. Physical examination reveals
splenomegaly and posterior cervical lymphadenopathy. A heterophile antibody test is positive. Which of
the following complications is most likely associated with this condition?
A. Aplastic anemia
B. Hemolytic uremic syndrome
C. Splenic rupture
D. Rheumatic fever
, Correct answer
C. Splenic rupture
RATIONALE: Infectious mononucleosis caused by Epstein-Barr virus can lead to splenomegaly, which
predisposes to splenic rupture, especially with contact sports or trauma.
Question 2
A 60-year-old male with a history of chronic alcohol abuse presents with confusion, ataxia, and
ophthalmoplegia. Which vitamin deficiency is most likely responsible for these symptoms?
A. Vitamin B12
B. Vitamin C
C. Vitamin B6
D. Vitamin B1
Correct answer
D. Vitamin B1
RATIONALE: Thiamine deficiency in chronic alcohol abuse leads to Wernicke encephalopathy,
characterized by confusion, ataxia, and ophthalmoplegia.
Question 3
A 36-year-old female presents with a malar rash, photosensitivity, and oral ulcers. Which autoantibody
is most specific for her likely diagnosis?
A. Anti-histone
B. Anti-Scl-70
C. Anti-dsDNA
D. Rheumatoid factor
Correct answer
C. Anti-dsDNA
RATIONALE: Anti-double-stranded DNA antibodies are highly specific for systemic lupus
erythematosus, which presents with malar rash, photosensitivity, and oral ulcers.
Question 4
A 64-year-old male presents with progressive dysphagia for solids and weight loss. Which of the
following is the most likely diagnosis?
A. Achalasia
B. Gastroesophageal reflux disease
C. Esophageal stricture
D. Esophageal carcinoma
Correct answer
D. Esophageal carcinoma
RATIONALE: Progressive dysphagia for solids and weight loss in an older male is concerning for
esophageal carcinoma, often associated with smoking and alcohol use.
, Question 5
A 30-year-old female presents with recurrent pregnancy loss. Which of the following is the most likely
underlying cause?
A. Factor V Leiden mutation
B. Protein C deficiency
C. Antiphospholipid syndrome
D. Systemic lupus erythematosus
Correct answer
C. Antiphospholipid syndrome
RATIONALE: Antiphospholipid syndrome is associated with recurrent arterial and venous
thrombosis, including recurrent pregnancy loss.
Question 6
A 47-year-old male presents with severe chest pain and is diagnosed with an acute myocardial
infarction. Which laboratory finding is most specific for myocardial injury?
A. Elevated lactate dehydrogenase
B. Elevated creatine kinase-MB
C. Elevated troponin I
D. Elevated aspartate aminotransferase
Correct answer
C. Elevated troponin I
RATIONALE: Troponin I is highly specific to cardiac muscle and is the preferred biomarker for
diagnosing myocardial infarction.
Question 7
A 32-year-old female is prescribed a drug that inhibits cyclooxygenase. Which therapeutic effect is most
directly attributed to this mechanism?
A. Enhanced gastric mucosal protection
B. Reduced fever and inflammation
C. Increased blood clotting
D. Bronchodilation
Correct answer
B. Reduced fever and inflammation
RATIONALE: Cyclooxygenase inhibition decreases prostaglandin synthesis, which reduces fever, pain,
and inflammation.
Question 8
A 69-year-old female presents with bone pain and hypercalcemia. Which underlying malignancy is most
likely?
A. Breast cancer
B. Lung cancer
