COMSAE Phase 1 Form 116 High-Yield Study
Guide:2026-2028 Newest Practice Questions,
Answers, and Explanations for COMLEX
Level 1 Prep | instant pdf download
Cardiovascular, Renal & Pulmonology
1. A 64-year-old male presents with tearing chest pain radiating to his back. His blood
pressure is 180/100 mmHg in the right arm and 140/80 mmHg in the left arm. What
is the most likely underlying pathology?
o A) Atherosclerotic plaque rupture
o B) Intimal tear of the aorta
o C) Myocardial infarction
o D) Pericardial effusion
o Explanation: An asymmetric blood pressure in the upper extremities paired
with tearing chest pain radiating to the back is a classic presentation of an
aortic dissection, which begins with an intimal tear.
2. A patient with chronic hypertension presents with progressive shortness of breath
and an echocardiogram showing an ejection fraction of 35%. Which medication is
indicated to reduce long-term mortality?
o A) Isosorbide dinitrate
o B) Furosemide
o C) Lisinopril
o D) Digoxin
o Explanation: ACE inhibitors like lisinopril have been conclusively proven to
decrease remodeling and reduce long-term mortality in patients with heart
failure with reduced ejection fraction (HFrEF).
,3. A 45-year-old female presents with fatigue and a serum potassium of 2.8 mEq/L. Her
aldosterone-to-renin ratio is significantly elevated. What is the most appropriate next
diagnostic step?
o A) Renal artery ultrasound
o B) CT scan of the adrenal glands
o C) 24-hour urine cortisol
o D) Plasma metanephrines
o Explanation: An elevated aldosterone-to-renin ratio indicates primary
hyperaldosteronism (Conn syndrome). An adrenal CT scan is the standard
initial imaging modality to localize an adenoma or look for bilateral
hyperplasia.
4. A 55-year-old male smoker presents with hemoptysis and weight loss. A biopsy
shows central cavitation and keratin pearls. What type of lung cancer does this
represent?
o A) Small cell carcinoma
o B) Large cell carcinoma
o C) Adenocarcinoma
o D) Squamous cell carcinoma
o Explanation: Squamous cell lung carcinoma is centrally located, strongly
linked to smoking, and classically characterized histologically by keratin
pearls and intercellular bridges.
5. A 24-year-old female with a history of asthma presents with progressive dyspnea.
Her arterial blood gas shows a pH of 7.50, pCO₂ of 30 mmHg, and pO₂ of 85 mmHg.
What is her acid-base status?
o A) Metabolic alkalosis
o B) Respiratory alkalosis
o C) Respiratory acidosis
o D) Metabolic acidosis
, o Explanation: A pH above 7.45 with a low pCO₂ (below 35 mmHg) defines a
primary respiratory alkalosis, which occurs due to hyperventilation during an
acute asthma exacerbation.
6. A 60-year-old male with chronic kidney disease presents with general malaise.
Laboratory analysis reveals a serum calcium of 7.2 mg/dL and phosphorus of 6.5
mg/dL. What bone pathology is he at risk for?
o A) Osteogenesis imperfecta
o B) Osteopetrosis
o C) Osteitis fibrosa cystica
o D) Paget disease of bone
o Explanation: Chronic kidney disease causes secondary hyperparathyroidism
due to hypocalcemia and hyperphosphatemia. Prolonged elevation of PTH
stimulates high bone turnover, leading to osteitis fibrosa cystica.
7. A patient presents with acute flank pain and hematuria. Urinalysis shows envelope-
shaped crystals. What is the most likely composition of these calculi?
o A) Magnesium ammonium phosphate
o B) Uric acid
o C) Calcium oxalate
o D) Cystine
o Explanation: Calcium oxalate crystals appear under light microscopy as
distinct, colorless, octahedral "envelopes" or dumbbells.
8. A 3-week-old infant is brought to the clinic due to cyanosis when crying. A harsh
holosystolic murmur is heard at the left lower sternal border. Echocardiography
demonstrates an overriding aorta. What is the diagnosis?
o A) Transposition of the great arteries
o B) Patent ductus arteriosus
o C) Tetralogy of Fallot
o D) Coarctation of the aorta
, o Explanation: Tetralogy of Fallot is characterized by a ventricular septal defect
(murmur), pulmonary stenosis, right ventricular hypertrophy, and an
overriding aorta.
9. A 72-year-old female experiences sudden severe dyspnea and right-sided chest pain
after a hip replacement. Her D-dimer is elevated. What is the first-line treatment if
she is hemodynamically stable?
o A) Tissue plasminogen activator (tPA)
o B) Low-molecular-weight heparin
o C) Embolectomy
o D) Aspirin
o Explanation: For a stable pulmonary embolism, systemic anticoagulation with
heparin or low-molecular-weight heparin is the standard first-line treatment to
prevent further clot propagation.
10. A biopsy of a kidney shows uniform thickening of the glomerular basement
membrane with "spike and dome" subepithelial deposits on electron microscopy.
What nephrotic syndrome is this?
o A) Minimal change disease
o B) Focal segmental glomerulosclerosis
o C) Membranous nephropathy
o D) IgA nephropathy
o Explanation: Membranous nephropathy is a common cause of nephrotic
syndrome in adults, identified by diffuse capillary wall thickening and granular
"spike and dome" subepithelial IgG/C3 deposits.
Gastrointestinal & Endocrine
11. A 42-year-old obese female presents with right upper quadrant pain that worsens
after fatty meals. Ultrasound reveals multiple gallstones. What hormone triggers this
pain?
o A) Secretin
o B) Gastrin
Guide:2026-2028 Newest Practice Questions,
Answers, and Explanations for COMLEX
Level 1 Prep | instant pdf download
Cardiovascular, Renal & Pulmonology
1. A 64-year-old male presents with tearing chest pain radiating to his back. His blood
pressure is 180/100 mmHg in the right arm and 140/80 mmHg in the left arm. What
is the most likely underlying pathology?
o A) Atherosclerotic plaque rupture
o B) Intimal tear of the aorta
o C) Myocardial infarction
o D) Pericardial effusion
o Explanation: An asymmetric blood pressure in the upper extremities paired
with tearing chest pain radiating to the back is a classic presentation of an
aortic dissection, which begins with an intimal tear.
2. A patient with chronic hypertension presents with progressive shortness of breath
and an echocardiogram showing an ejection fraction of 35%. Which medication is
indicated to reduce long-term mortality?
o A) Isosorbide dinitrate
o B) Furosemide
o C) Lisinopril
o D) Digoxin
o Explanation: ACE inhibitors like lisinopril have been conclusively proven to
decrease remodeling and reduce long-term mortality in patients with heart
failure with reduced ejection fraction (HFrEF).
,3. A 45-year-old female presents with fatigue and a serum potassium of 2.8 mEq/L. Her
aldosterone-to-renin ratio is significantly elevated. What is the most appropriate next
diagnostic step?
o A) Renal artery ultrasound
o B) CT scan of the adrenal glands
o C) 24-hour urine cortisol
o D) Plasma metanephrines
o Explanation: An elevated aldosterone-to-renin ratio indicates primary
hyperaldosteronism (Conn syndrome). An adrenal CT scan is the standard
initial imaging modality to localize an adenoma or look for bilateral
hyperplasia.
4. A 55-year-old male smoker presents with hemoptysis and weight loss. A biopsy
shows central cavitation and keratin pearls. What type of lung cancer does this
represent?
o A) Small cell carcinoma
o B) Large cell carcinoma
o C) Adenocarcinoma
o D) Squamous cell carcinoma
o Explanation: Squamous cell lung carcinoma is centrally located, strongly
linked to smoking, and classically characterized histologically by keratin
pearls and intercellular bridges.
5. A 24-year-old female with a history of asthma presents with progressive dyspnea.
Her arterial blood gas shows a pH of 7.50, pCO₂ of 30 mmHg, and pO₂ of 85 mmHg.
What is her acid-base status?
o A) Metabolic alkalosis
o B) Respiratory alkalosis
o C) Respiratory acidosis
o D) Metabolic acidosis
, o Explanation: A pH above 7.45 with a low pCO₂ (below 35 mmHg) defines a
primary respiratory alkalosis, which occurs due to hyperventilation during an
acute asthma exacerbation.
6. A 60-year-old male with chronic kidney disease presents with general malaise.
Laboratory analysis reveals a serum calcium of 7.2 mg/dL and phosphorus of 6.5
mg/dL. What bone pathology is he at risk for?
o A) Osteogenesis imperfecta
o B) Osteopetrosis
o C) Osteitis fibrosa cystica
o D) Paget disease of bone
o Explanation: Chronic kidney disease causes secondary hyperparathyroidism
due to hypocalcemia and hyperphosphatemia. Prolonged elevation of PTH
stimulates high bone turnover, leading to osteitis fibrosa cystica.
7. A patient presents with acute flank pain and hematuria. Urinalysis shows envelope-
shaped crystals. What is the most likely composition of these calculi?
o A) Magnesium ammonium phosphate
o B) Uric acid
o C) Calcium oxalate
o D) Cystine
o Explanation: Calcium oxalate crystals appear under light microscopy as
distinct, colorless, octahedral "envelopes" or dumbbells.
8. A 3-week-old infant is brought to the clinic due to cyanosis when crying. A harsh
holosystolic murmur is heard at the left lower sternal border. Echocardiography
demonstrates an overriding aorta. What is the diagnosis?
o A) Transposition of the great arteries
o B) Patent ductus arteriosus
o C) Tetralogy of Fallot
o D) Coarctation of the aorta
, o Explanation: Tetralogy of Fallot is characterized by a ventricular septal defect
(murmur), pulmonary stenosis, right ventricular hypertrophy, and an
overriding aorta.
9. A 72-year-old female experiences sudden severe dyspnea and right-sided chest pain
after a hip replacement. Her D-dimer is elevated. What is the first-line treatment if
she is hemodynamically stable?
o A) Tissue plasminogen activator (tPA)
o B) Low-molecular-weight heparin
o C) Embolectomy
o D) Aspirin
o Explanation: For a stable pulmonary embolism, systemic anticoagulation with
heparin or low-molecular-weight heparin is the standard first-line treatment to
prevent further clot propagation.
10. A biopsy of a kidney shows uniform thickening of the glomerular basement
membrane with "spike and dome" subepithelial deposits on electron microscopy.
What nephrotic syndrome is this?
o A) Minimal change disease
o B) Focal segmental glomerulosclerosis
o C) Membranous nephropathy
o D) IgA nephropathy
o Explanation: Membranous nephropathy is a common cause of nephrotic
syndrome in adults, identified by diffuse capillary wall thickening and granular
"spike and dome" subepithelial IgG/C3 deposits.
Gastrointestinal & Endocrine
11. A 42-year-old obese female presents with right upper quadrant pain that worsens
after fatty meals. Ultrasound reveals multiple gallstones. What hormone triggers this
pain?
o A) Secretin
o B) Gastrin
