COMSAE PHASE 1 FORM 115 EXAM – QUESTIONS AND ANSWERS | VERIFIED AND WELL
DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
*Core Domains:*
*- Osteopathic Manipulative Medicine (OMM) and Neuromusculoskeletal Medicine*
*- Cardiovascular System & Hematology*
*- Respiratory & Renal Systems*
*- Gastrointestinal & Endocrine Systems*
*- Reproductive & Urinary Systems*
*- Psychiatry & Behavioral Science*
*- Neurology & Special Senses*
*- Microbiology, Immunology & Infectious Disease*
*- Public Health, Ethics & Legal Medicine*
*Introduction*
*The COMSAE Phase 1 Form 115 Exam is a comprehensive assessment designed to evaluate a candidate's
Section One: Questions 1–100
Question 1
A 45-year-old male presents with a 3-month history of burning epigastric pain that worsens 2 to 3 hours
after meals and is occasionally relieved by food or antacids. Physical examination reveals mild
epigastric tenderness. A urea breath test is positive. Which of the following is the most likely primary
mechanism of injury causing this patient's condition?
A. Direct autoimmune destruction of parietal cells
,B. Decreased somatostatin secretion leading to hypergastrinemia
C. Chemical irritation from chronic bile reflux
D. Ischemic mucosal injury due to microvascular disease
🟢 B. Decreased somatostatin secretion leading to hypergastrinemia
🔴 Explanation: Helicobacter pylori infection causing antral-predominant gastritis leads to a decrease
in somatostatin-producing D cells. This reduction in somatostatin disinhibits gastrin release, causing
hypergastrinemia and subsequent increased acid production from parietal cells, predisposing the
patient to duodenal ulcers.
Question 2
A 24-year-old female presents to the clinic complaining of a 2-week history of fatigue, weight gain, and
cold intolerance. Physical examination demonstrates a diffusely enlarged, non-tender thyroid gland.
Laboratory evaluation shows an elevated thyroid-stimulating hormone (TSH) level and a decreased
free T4 level. Which of the following histopathological findings is most characteristic of this patient’s
condition?
A. Granulomatous inflammation with multinucleated giant cells
B. Lymphocytic infiltrate with germinal centers and Hurthle cells
C. Extensive fibrosis extending beyond the thyroid capsule
D. Extracellular amyloid deposits staining with Congo red
🟢 B. Lymphocytic infiltrate with germinal centers and Hurthle cells
🔴 Explanation: Hashimoto thyroiditis is the most common cause of hypothyroidism in iodine-sufficient
areas. It is characterized histologically by a prominent lymphocytic infiltrate with germinal center
formation and Hurthle cells (epithelial cells with abundant eosinophilic, granular cytoplasm).
Question 3
A 62-year-old male with a history of chronic hypertension presents to the emergency department with
sudden-onset, tearing chest pain that radiates to his back. His blood pressure is 185/105 mmHg in the
right arm and 150/85 mmHg in the left arm. Chest radiograph reveals a widened mediastinum. Which
of the following is the primary predisposing histopathological change associated with this patient's
acute condition?
A. Intimal tear with atherosclerotic plaque rupture
,B. Cystic medial degeneration of the aortic wall
C. Segmental transmural inflammation with fibrinoid necrosis
D. Granulomatous inflammation of the aortic arch
🟢 B. Cystic medial degeneration of the aortic wall
🔴 Explanation: Aortic dissection is strongly associated with chronic hypertension, which accelerates
cystic medial degeneration (loss of smooth muscle cells and elastic tissue within the aortic media). This
structural weakening predisposes the vessel to an intimal tear and subsequent dissecting hematoma.
Question 4
A 68-year-old female is brought to the emergency department due to a 2-day history of progressive
confusion, lethargy, and general weakness. Her medical history is significant for small cell lung
carcinoma. Laboratory studies reveal a serum sodium level of 118 mEq/L, serum osmolality of 245
mOsm/kg, and urine osmolality of 450 mOsm/kg. Which of the following is the most appropriate initial
management step for this patient's electrolyte abnormality?
A. Aggressive intravenous administration of 3% hypertonic saline
B. Fluid restriction and administration of an oral loop diuretic
C. Intravenous bolus of 0.9% normal saline
D. Intravenous administration of desmopressin
🟢 A. Aggressive intravenous administration of 3% hypertonic saline
🔴 Explanation: This patient has severe, symptomatic hyponatremia secondary to the Syndrome of
Inappropriate Antidiuretic Hormone (SIADH) secretion from small cell lung cancer. For patients with
severe neurologic symptoms (confusion, lethargy, seizures), hypertonic (3%) saline is indicated to
acutely raise serum sodium and prevent cerebral edema, taking care not to exceed 8-12 mEq/L in 24
hours to avoid osmotic demyelination syndrome.
Question 5
A 31-year-old pregnant female at 34 weeks gestation presents for a routine prenatal visit. Her blood
pressure is 152/96 mmHg on two separate readings 4 hours apart. Urinalysis reveals 2+ protein. She
denies headaches, visual changes, or right upper quadrant pain. Which of the following pathological
mechanisms best explains the development of this patient's condition?
A. Increased maternal production of aldosterone
, B. Abnormal spiral artery remodeling leading to placental ischemia
C. Diffuse immune-complex deposition in the renal glomeruli
D. Excessive sympathetic nervous system activation
🟢 B. Abnormal spiral artery remodeling leading to placental ischemia
🔴 Explanation: Preeclampsia is driven by abnormal cytotrophoblast invasion of the uterine spiral
arteries, preventing their remodeling into low-resistance, high-caliber vessels. The resulting placental
ischemia releases anti-angiogenic factors into maternal circulation, causing widespread endothelial
dysfunction, hypertension, and proteinuria.
Question 6
A 9-month-old infant is brought to the pediatrician due to persistent coughing spells followed by a loud
inspiratory sound. The mother notes that the child's face turns red during these episodes, which have
been occurring for the past week. The infant has not received routine immunizations. Which of the
following virulence factors of the causative organism directly damages ciliated respiratory epithelial
cells?
A. Tracheal cytotoxin
B. Pertussis toxin
C. Adenylate cyclase toxin
D. Filamentous hemagglutinin
🟢 A. Tracheal cytotoxin
🔴 Explanation: Bordetella pertussis causes whooping cough. Tracheal cytotoxin is a peptidoglycan
fragment produced by the bacteria that specifically paralyzes and destroys ciliated respiratory epithelial
cells, preventing normal mucociliary clearance and leading to the characteristic paroxysmal cough.
Question 7
A 55-year-old female presents to her osteopathic physician complaining of persistent pain and stiffness
in both hands for the past 6 months. She notes that the stiffness lasts for over an hour every morning.
Physical examination reveals soft tissue swelling and tenderness of the bilateral metacarpophalangeal
(MCP) and proximal interphalangeal (PIP) joints. Laboratory testing is positive for anti-cyclic
citrullinated peptide (anti-CCP) antibodies. Which of the following HLA alleles is most strongly
associated with this condition?
DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
*Core Domains:*
*- Osteopathic Manipulative Medicine (OMM) and Neuromusculoskeletal Medicine*
*- Cardiovascular System & Hematology*
*- Respiratory & Renal Systems*
*- Gastrointestinal & Endocrine Systems*
*- Reproductive & Urinary Systems*
*- Psychiatry & Behavioral Science*
*- Neurology & Special Senses*
*- Microbiology, Immunology & Infectious Disease*
*- Public Health, Ethics & Legal Medicine*
*Introduction*
*The COMSAE Phase 1 Form 115 Exam is a comprehensive assessment designed to evaluate a candidate's
Section One: Questions 1–100
Question 1
A 45-year-old male presents with a 3-month history of burning epigastric pain that worsens 2 to 3 hours
after meals and is occasionally relieved by food or antacids. Physical examination reveals mild
epigastric tenderness. A urea breath test is positive. Which of the following is the most likely primary
mechanism of injury causing this patient's condition?
A. Direct autoimmune destruction of parietal cells
,B. Decreased somatostatin secretion leading to hypergastrinemia
C. Chemical irritation from chronic bile reflux
D. Ischemic mucosal injury due to microvascular disease
🟢 B. Decreased somatostatin secretion leading to hypergastrinemia
🔴 Explanation: Helicobacter pylori infection causing antral-predominant gastritis leads to a decrease
in somatostatin-producing D cells. This reduction in somatostatin disinhibits gastrin release, causing
hypergastrinemia and subsequent increased acid production from parietal cells, predisposing the
patient to duodenal ulcers.
Question 2
A 24-year-old female presents to the clinic complaining of a 2-week history of fatigue, weight gain, and
cold intolerance. Physical examination demonstrates a diffusely enlarged, non-tender thyroid gland.
Laboratory evaluation shows an elevated thyroid-stimulating hormone (TSH) level and a decreased
free T4 level. Which of the following histopathological findings is most characteristic of this patient’s
condition?
A. Granulomatous inflammation with multinucleated giant cells
B. Lymphocytic infiltrate with germinal centers and Hurthle cells
C. Extensive fibrosis extending beyond the thyroid capsule
D. Extracellular amyloid deposits staining with Congo red
🟢 B. Lymphocytic infiltrate with germinal centers and Hurthle cells
🔴 Explanation: Hashimoto thyroiditis is the most common cause of hypothyroidism in iodine-sufficient
areas. It is characterized histologically by a prominent lymphocytic infiltrate with germinal center
formation and Hurthle cells (epithelial cells with abundant eosinophilic, granular cytoplasm).
Question 3
A 62-year-old male with a history of chronic hypertension presents to the emergency department with
sudden-onset, tearing chest pain that radiates to his back. His blood pressure is 185/105 mmHg in the
right arm and 150/85 mmHg in the left arm. Chest radiograph reveals a widened mediastinum. Which
of the following is the primary predisposing histopathological change associated with this patient's
acute condition?
A. Intimal tear with atherosclerotic plaque rupture
,B. Cystic medial degeneration of the aortic wall
C. Segmental transmural inflammation with fibrinoid necrosis
D. Granulomatous inflammation of the aortic arch
🟢 B. Cystic medial degeneration of the aortic wall
🔴 Explanation: Aortic dissection is strongly associated with chronic hypertension, which accelerates
cystic medial degeneration (loss of smooth muscle cells and elastic tissue within the aortic media). This
structural weakening predisposes the vessel to an intimal tear and subsequent dissecting hematoma.
Question 4
A 68-year-old female is brought to the emergency department due to a 2-day history of progressive
confusion, lethargy, and general weakness. Her medical history is significant for small cell lung
carcinoma. Laboratory studies reveal a serum sodium level of 118 mEq/L, serum osmolality of 245
mOsm/kg, and urine osmolality of 450 mOsm/kg. Which of the following is the most appropriate initial
management step for this patient's electrolyte abnormality?
A. Aggressive intravenous administration of 3% hypertonic saline
B. Fluid restriction and administration of an oral loop diuretic
C. Intravenous bolus of 0.9% normal saline
D. Intravenous administration of desmopressin
🟢 A. Aggressive intravenous administration of 3% hypertonic saline
🔴 Explanation: This patient has severe, symptomatic hyponatremia secondary to the Syndrome of
Inappropriate Antidiuretic Hormone (SIADH) secretion from small cell lung cancer. For patients with
severe neurologic symptoms (confusion, lethargy, seizures), hypertonic (3%) saline is indicated to
acutely raise serum sodium and prevent cerebral edema, taking care not to exceed 8-12 mEq/L in 24
hours to avoid osmotic demyelination syndrome.
Question 5
A 31-year-old pregnant female at 34 weeks gestation presents for a routine prenatal visit. Her blood
pressure is 152/96 mmHg on two separate readings 4 hours apart. Urinalysis reveals 2+ protein. She
denies headaches, visual changes, or right upper quadrant pain. Which of the following pathological
mechanisms best explains the development of this patient's condition?
A. Increased maternal production of aldosterone
, B. Abnormal spiral artery remodeling leading to placental ischemia
C. Diffuse immune-complex deposition in the renal glomeruli
D. Excessive sympathetic nervous system activation
🟢 B. Abnormal spiral artery remodeling leading to placental ischemia
🔴 Explanation: Preeclampsia is driven by abnormal cytotrophoblast invasion of the uterine spiral
arteries, preventing their remodeling into low-resistance, high-caliber vessels. The resulting placental
ischemia releases anti-angiogenic factors into maternal circulation, causing widespread endothelial
dysfunction, hypertension, and proteinuria.
Question 6
A 9-month-old infant is brought to the pediatrician due to persistent coughing spells followed by a loud
inspiratory sound. The mother notes that the child's face turns red during these episodes, which have
been occurring for the past week. The infant has not received routine immunizations. Which of the
following virulence factors of the causative organism directly damages ciliated respiratory epithelial
cells?
A. Tracheal cytotoxin
B. Pertussis toxin
C. Adenylate cyclase toxin
D. Filamentous hemagglutinin
🟢 A. Tracheal cytotoxin
🔴 Explanation: Bordetella pertussis causes whooping cough. Tracheal cytotoxin is a peptidoglycan
fragment produced by the bacteria that specifically paralyzes and destroys ciliated respiratory epithelial
cells, preventing normal mucociliary clearance and leading to the characteristic paroxysmal cough.
Question 7
A 55-year-old female presents to her osteopathic physician complaining of persistent pain and stiffness
in both hands for the past 6 months. She notes that the stiffness lasts for over an hour every morning.
Physical examination reveals soft tissue swelling and tenderness of the bilateral metacarpophalangeal
(MCP) and proximal interphalangeal (PIP) joints. Laboratory testing is positive for anti-cyclic
citrullinated peptide (anti-CCP) antibodies. Which of the following HLA alleles is most strongly
associated with this condition?
