USMLE Step 2 CK EXAM |ACTUAL QUESTIONS
AND ANSWERS|GRADED A+
SECTION 1: INTERNAL MEDICINE
1. A 55-year-old man with a 40 pack-year smoking history presents with
substernal chest pain that occurs with exertion and is relieved by rest. What is
the most appropriate initial diagnostic test?
• A) Exercise stress test
• B) Coronary angiography
• C) Echocardiogram
• D) Cardiac CT
Correct Answer: A
Rationale: This patient's presentation is consistent with stable angina. The most
appropriate initial diagnostic test is an exercise stress test to evaluate for inducible
ischemia. Coronary angiography is reserved for patients with high-risk features or
positive stress tests. Echocardiogram is used to assess ventricular function but is
not the initial diagnostic test for stable angina.
2. A 65-year-old woman with a history of hypertension presents with
progressive dyspnea, orthopnea, and paroxysmal nocturnal dyspnea. Physical
exam reveals crackles at the lung bases, an S3 gallop, and jugular venous
distention. What is the most appropriate initial pharmacotherapy?
• A) Furosemide
• B) Metoprolol succinate
, • C) Lisinopril
• D) Spironolactone
Correct Answer: A
Rationale: This patient is presenting with acute decompensated heart failure.
Furosemide is the diuretic of choice for acute symptom relief by reducing preload
and alleviating pulmonary congestion. Metoprolol, lisinopril, and spironolactone
are chronic therapies that do not provide immediate symptom relief in acute heart
failure.
3. A 45-year-old woman presents with fatigue, joint pain, and a malar rash.
Laboratory studies show positive ANA, anti-dsDNA, and low complement levels.
What is the most likely diagnosis?
• A) Systemic lupus erythematosus (SLE)
• B) Rheumatoid arthritis
• C) Sjögren syndrome
• D) Scleroderma
Correct Answer: A
Rationale: SLE is characterized by malar rash, photosensitivity, oral ulcers,
arthritis, and positive ANA with anti-dsDNA. Low complement levels indicate
active disease. Anti-dsDNA is associated with lupus nephritis. The diagnosis meets
the EULAR/ACR classification criteria for SLE.
4. A 65-year-old man with COPD has an SpO₂ of 88% on room air. What is the
most appropriate oxygen target for this patient?
• A) SpO₂ 100%
• B) SpO₂ 88-92%
• C) SpO₂ 94-98%
, • D) SpO₂ 90-95%
Correct Answer: B
*Rationale: In COPD patients, the target SpO₂ is 88-92% to avoid suppressing the
hypoxic drive and causing hypercapnic respiratory failure. Over-oxygenation can
lead to CO₂ retention and respiratory acidosis. The hypoxic drive is a key concept
in COPD management.*
5. A 55-year-old man presents with acute epigastric pain radiating to the back,
nausea, and vomiting. He has a history of alcohol use disorder. Serum lipase is
850 U/L (normal < 60). What is the most appropriate initial management?
• A) NPO, IV fluids, pain management
• B) Early enteral nutrition
• C) Total parenteral nutrition (TPN)
• D) Antibiotics
Correct Answer: A
Rationale: Acute pancreatitis is diagnosed with epigastric pain radiating to the
back and lipase > 3 times the upper limit of normal. Initial management includes
NPO status, aggressive IV fluid resuscitation, and pain management. Early enteral
nutrition is recommended in severe pancreatitis but is not the initial step.
6. A 28-year-old woman with type 1 diabetes presents with nausea, vomiting,
abdominal pain, and Kussmaul respirations. Arterial blood gas shows pH 7.15,
bicarbonate 12 mEq/L, and anion gap 22. What is the most appropriate fluid of
choice for initial resuscitation?
• A) 0.9% normal saline
• B) 0.45% normal saline
• C) D5W
, • D) Lactated Ringer's
Correct Answer: A
*Rationale: DKA requires IV fluid resuscitation with 0.9% normal saline to restore
intravascular volume. 0.45% saline is used after volume resuscitation. D5W is
added when glucose falls to 250 mg/dL to prevent hypoglycemia.*
7. A 55-year-old woman presents with progressive dysphagia, weight loss, and
hoarseness. She has a history of GERD and a 40 pack-year smoking history.
Upper endoscopy reveals a distal esophageal mass. Biopsy shows
adenocarcinoma. What is the most likely precursor lesion?
• A) Barrett esophagus
• B) Squamous metaplasia
• C) Gastric metaplasia
• D) Achalasia
Correct Answer: A
Rationale: Barrett esophagus is a metaplastic change from squamous to columnar
epithelium in the distal esophagus caused by chronic GERD. It is a precursor to
esophageal adenocarcinoma. Risk factors include GERD, obesity, and smoking.
8. A 45-year-old woman presents with a breast mass. Mammogram shows a
spiculated mass with microcalcifications. Biopsy reveals invasive ductal
carcinoma. The tumor is ER/PR positive and HER2 negative. What is the most
appropriate first-line therapy for this premenopausal patient?
• A) Tamoxifen
• B) Trastuzumab
• C) Aromatase inhibitor
• D) Chemotherapy
AND ANSWERS|GRADED A+
SECTION 1: INTERNAL MEDICINE
1. A 55-year-old man with a 40 pack-year smoking history presents with
substernal chest pain that occurs with exertion and is relieved by rest. What is
the most appropriate initial diagnostic test?
• A) Exercise stress test
• B) Coronary angiography
• C) Echocardiogram
• D) Cardiac CT
Correct Answer: A
Rationale: This patient's presentation is consistent with stable angina. The most
appropriate initial diagnostic test is an exercise stress test to evaluate for inducible
ischemia. Coronary angiography is reserved for patients with high-risk features or
positive stress tests. Echocardiogram is used to assess ventricular function but is
not the initial diagnostic test for stable angina.
2. A 65-year-old woman with a history of hypertension presents with
progressive dyspnea, orthopnea, and paroxysmal nocturnal dyspnea. Physical
exam reveals crackles at the lung bases, an S3 gallop, and jugular venous
distention. What is the most appropriate initial pharmacotherapy?
• A) Furosemide
• B) Metoprolol succinate
, • C) Lisinopril
• D) Spironolactone
Correct Answer: A
Rationale: This patient is presenting with acute decompensated heart failure.
Furosemide is the diuretic of choice for acute symptom relief by reducing preload
and alleviating pulmonary congestion. Metoprolol, lisinopril, and spironolactone
are chronic therapies that do not provide immediate symptom relief in acute heart
failure.
3. A 45-year-old woman presents with fatigue, joint pain, and a malar rash.
Laboratory studies show positive ANA, anti-dsDNA, and low complement levels.
What is the most likely diagnosis?
• A) Systemic lupus erythematosus (SLE)
• B) Rheumatoid arthritis
• C) Sjögren syndrome
• D) Scleroderma
Correct Answer: A
Rationale: SLE is characterized by malar rash, photosensitivity, oral ulcers,
arthritis, and positive ANA with anti-dsDNA. Low complement levels indicate
active disease. Anti-dsDNA is associated with lupus nephritis. The diagnosis meets
the EULAR/ACR classification criteria for SLE.
4. A 65-year-old man with COPD has an SpO₂ of 88% on room air. What is the
most appropriate oxygen target for this patient?
• A) SpO₂ 100%
• B) SpO₂ 88-92%
• C) SpO₂ 94-98%
, • D) SpO₂ 90-95%
Correct Answer: B
*Rationale: In COPD patients, the target SpO₂ is 88-92% to avoid suppressing the
hypoxic drive and causing hypercapnic respiratory failure. Over-oxygenation can
lead to CO₂ retention and respiratory acidosis. The hypoxic drive is a key concept
in COPD management.*
5. A 55-year-old man presents with acute epigastric pain radiating to the back,
nausea, and vomiting. He has a history of alcohol use disorder. Serum lipase is
850 U/L (normal < 60). What is the most appropriate initial management?
• A) NPO, IV fluids, pain management
• B) Early enteral nutrition
• C) Total parenteral nutrition (TPN)
• D) Antibiotics
Correct Answer: A
Rationale: Acute pancreatitis is diagnosed with epigastric pain radiating to the
back and lipase > 3 times the upper limit of normal. Initial management includes
NPO status, aggressive IV fluid resuscitation, and pain management. Early enteral
nutrition is recommended in severe pancreatitis but is not the initial step.
6. A 28-year-old woman with type 1 diabetes presents with nausea, vomiting,
abdominal pain, and Kussmaul respirations. Arterial blood gas shows pH 7.15,
bicarbonate 12 mEq/L, and anion gap 22. What is the most appropriate fluid of
choice for initial resuscitation?
• A) 0.9% normal saline
• B) 0.45% normal saline
• C) D5W
, • D) Lactated Ringer's
Correct Answer: A
*Rationale: DKA requires IV fluid resuscitation with 0.9% normal saline to restore
intravascular volume. 0.45% saline is used after volume resuscitation. D5W is
added when glucose falls to 250 mg/dL to prevent hypoglycemia.*
7. A 55-year-old woman presents with progressive dysphagia, weight loss, and
hoarseness. She has a history of GERD and a 40 pack-year smoking history.
Upper endoscopy reveals a distal esophageal mass. Biopsy shows
adenocarcinoma. What is the most likely precursor lesion?
• A) Barrett esophagus
• B) Squamous metaplasia
• C) Gastric metaplasia
• D) Achalasia
Correct Answer: A
Rationale: Barrett esophagus is a metaplastic change from squamous to columnar
epithelium in the distal esophagus caused by chronic GERD. It is a precursor to
esophageal adenocarcinoma. Risk factors include GERD, obesity, and smoking.
8. A 45-year-old woman presents with a breast mass. Mammogram shows a
spiculated mass with microcalcifications. Biopsy reveals invasive ductal
carcinoma. The tumor is ER/PR positive and HER2 negative. What is the most
appropriate first-line therapy for this premenopausal patient?
• A) Tamoxifen
• B) Trastuzumab
• C) Aromatase inhibitor
• D) Chemotherapy