USMLE Step 2 CK Practice Questions &
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Answers | 2025 High-Yield Clinical
| | | | |
Review
This |document |includes |50 |high-yield, |clinically |oriented |multiple-choice |questions |(MCQs) |
for |USMLE |Step |2 |CK. |Each |question |is |case-based |and |accompanied |by |a |detailed |rationale |
to |enhance |your |understanding. |Topics |include |internal |medicine, |pediatrics, |OB/GYN, |
surgery, |psychiatry, |and |emergency |medicine.
1. Q1: |A |67-year-old |man |presents |with |chest |pain |radiating |to |his |left |arm |and |shortness |
of |breath. |ECG |shows |ST |elevations |in |leads |II, |III, |and |aVF. |What |is |the |most |likely |
diagnosis?
Answer: |Inferior |wall |myocardial |infarction.
Rationale: |ST |elevation |in |these |leads |suggests |RCA |occlusion.
2. Q2: |A |24-year-old |woman |with |sudden-onset |lower |abdominal |pain, |positive |pregnancy
|test, |and |no |intrauterine |pregnancy |on |ultrasound. |What |is |the |diagnosis?
Answer: |Ectopic |pregnancy.
Rationale: |Classic |presentation—pregnancy |with |empty |uterus |and |abdominal |pain.
3. Q3: |A |58-year-old |man |presents |with |black |stools |and |fatigue. |His |hemoglobin |is |6.5 |
g/dL. |What |is |the |next |best |step |in |management?
Answer: |Upper |endoscopy.
Rationale: |Melena |suggests |upper |GI |bleed, |requiring |endoscopic |evaluation.
4. Q4: |A |3-year-old |presents |with |a |barking |cough |and |inspiratory |stridor. |What |is |the |
most |likely |diagnosis?
Answer: |Croup |(laryngotracheobronchitis).
Rationale: |Caused |by |parainfluenza |virus, |responds |to |steroids |and |nebulized |epinephrine.
5. Q5: |A |woman |in |her |third |trimester |presents |with |hypertension, |proteinuria, |and |
elevated |liver |enzymes. |What |is |the |diagnosis?
Answer: |Preeclampsia |with |severe |features.
Rationale: |Severe |disease |requires |monitoring |or |delivery.
6. Q6: |A |65-year-old |man |with |COPD |presents |with |confusion |and |asterixis. |Labs |show |
CO2 |retention. |What |is |the |likely |cause?
, Answer: |Hypercapnic |encephalopathy.
Rationale: |CO2 |narcosis |in |decompensated |COPD.
7. Q7: |A |patient |with |bipolar |disorder |is |taking |lithium |and |develops |polyuria |and |
polydipsia. |Serum |Na+ |is |150. |Diagnosis?
Answer: |Nephrogenic |diabetes |insipidus.
Rationale: |Lithium-induced |resistance |to |ADH.
8. Q8: |A |21-year-old |college |student |presents |with |fever, |sore |throat, |lymphadenopathy, |
and |splenomegaly. |What |test |confirms |the |diagnosis?
Answer: |Heterophile |antibody |(Monospot) |test.
Rationale: |For |diagnosis |of |EBV |infectious |mononucleosis.
9. Q9: |A |45-year-old |woman |complains |of |fatigue |and |pruritus. |Labs |show |elevated |ALP |
and |AMA |positivity. |Most |likely |diagnosis?
Answer: |Primary |biliary |cholangitis.
Rationale: |Autoimmune |destruction |of |intrahepatic |bile |ducts.
10. Q10: |A |trauma |patient |has |absent |breath |sounds |on |the |left |and |tracheal |deviation |to |
the |right. |Diagnosis?
Answer: |Tension |pneumothorax.
Rationale: |Medical |emergency |requiring |needle |decompression.
11. Q11: |A |67-year-old |man |presents |with |chest |pain |radiating |to |his |left |arm |and |
shortness |of |breath. |ECG |shows |ST |elevations |in |leads |II, |III, |and |aVF. |What |is |the |most |
likely |diagnosis?
Answer: |Inferior |wall |myocardial |infarction.
Rationale: |ST |elevation |in |these |leads |suggests |RCA |occlusion.
12. Q12: |A |24-year-old |woman |with |sudden-onset |lower |abdominal |pain, |positive |
pregnancy |test, |and |no |intrauterine |pregnancy |on |ultrasound. |What |is |the |diagnosis?
Answer: |Ectopic |pregnancy.
Rationale: |Classic |presentation—pregnancy |with |empty |uterus |and |abdominal |pain.
13. Q13: |A |58-year-old |man |presents |with |black |stools |and |fatigue. |His |hemoglobin |is |6.5 |
g/dL. |What |is |the |next |best |step |in |management?
Answer: |Upper |endoscopy.
Rationale: |Melena |suggests |upper |GI |bleed, |requiring |endoscopic |evaluation.
14. Q14: |A |3-year-old |presents |with |a |barking |cough |and |inspiratory |stridor. |What |is |the |
most |likely |diagnosis?
| | | | | | |
Answers | 2025 High-Yield Clinical
| | | | |
Review
This |document |includes |50 |high-yield, |clinically |oriented |multiple-choice |questions |(MCQs) |
for |USMLE |Step |2 |CK. |Each |question |is |case-based |and |accompanied |by |a |detailed |rationale |
to |enhance |your |understanding. |Topics |include |internal |medicine, |pediatrics, |OB/GYN, |
surgery, |psychiatry, |and |emergency |medicine.
1. Q1: |A |67-year-old |man |presents |with |chest |pain |radiating |to |his |left |arm |and |shortness |
of |breath. |ECG |shows |ST |elevations |in |leads |II, |III, |and |aVF. |What |is |the |most |likely |
diagnosis?
Answer: |Inferior |wall |myocardial |infarction.
Rationale: |ST |elevation |in |these |leads |suggests |RCA |occlusion.
2. Q2: |A |24-year-old |woman |with |sudden-onset |lower |abdominal |pain, |positive |pregnancy
|test, |and |no |intrauterine |pregnancy |on |ultrasound. |What |is |the |diagnosis?
Answer: |Ectopic |pregnancy.
Rationale: |Classic |presentation—pregnancy |with |empty |uterus |and |abdominal |pain.
3. Q3: |A |58-year-old |man |presents |with |black |stools |and |fatigue. |His |hemoglobin |is |6.5 |
g/dL. |What |is |the |next |best |step |in |management?
Answer: |Upper |endoscopy.
Rationale: |Melena |suggests |upper |GI |bleed, |requiring |endoscopic |evaluation.
4. Q4: |A |3-year-old |presents |with |a |barking |cough |and |inspiratory |stridor. |What |is |the |
most |likely |diagnosis?
Answer: |Croup |(laryngotracheobronchitis).
Rationale: |Caused |by |parainfluenza |virus, |responds |to |steroids |and |nebulized |epinephrine.
5. Q5: |A |woman |in |her |third |trimester |presents |with |hypertension, |proteinuria, |and |
elevated |liver |enzymes. |What |is |the |diagnosis?
Answer: |Preeclampsia |with |severe |features.
Rationale: |Severe |disease |requires |monitoring |or |delivery.
6. Q6: |A |65-year-old |man |with |COPD |presents |with |confusion |and |asterixis. |Labs |show |
CO2 |retention. |What |is |the |likely |cause?
, Answer: |Hypercapnic |encephalopathy.
Rationale: |CO2 |narcosis |in |decompensated |COPD.
7. Q7: |A |patient |with |bipolar |disorder |is |taking |lithium |and |develops |polyuria |and |
polydipsia. |Serum |Na+ |is |150. |Diagnosis?
Answer: |Nephrogenic |diabetes |insipidus.
Rationale: |Lithium-induced |resistance |to |ADH.
8. Q8: |A |21-year-old |college |student |presents |with |fever, |sore |throat, |lymphadenopathy, |
and |splenomegaly. |What |test |confirms |the |diagnosis?
Answer: |Heterophile |antibody |(Monospot) |test.
Rationale: |For |diagnosis |of |EBV |infectious |mononucleosis.
9. Q9: |A |45-year-old |woman |complains |of |fatigue |and |pruritus. |Labs |show |elevated |ALP |
and |AMA |positivity. |Most |likely |diagnosis?
Answer: |Primary |biliary |cholangitis.
Rationale: |Autoimmune |destruction |of |intrahepatic |bile |ducts.
10. Q10: |A |trauma |patient |has |absent |breath |sounds |on |the |left |and |tracheal |deviation |to |
the |right. |Diagnosis?
Answer: |Tension |pneumothorax.
Rationale: |Medical |emergency |requiring |needle |decompression.
11. Q11: |A |67-year-old |man |presents |with |chest |pain |radiating |to |his |left |arm |and |
shortness |of |breath. |ECG |shows |ST |elevations |in |leads |II, |III, |and |aVF. |What |is |the |most |
likely |diagnosis?
Answer: |Inferior |wall |myocardial |infarction.
Rationale: |ST |elevation |in |these |leads |suggests |RCA |occlusion.
12. Q12: |A |24-year-old |woman |with |sudden-onset |lower |abdominal |pain, |positive |
pregnancy |test, |and |no |intrauterine |pregnancy |on |ultrasound. |What |is |the |diagnosis?
Answer: |Ectopic |pregnancy.
Rationale: |Classic |presentation—pregnancy |with |empty |uterus |and |abdominal |pain.
13. Q13: |A |58-year-old |man |presents |with |black |stools |and |fatigue. |His |hemoglobin |is |6.5 |
g/dL. |What |is |the |next |best |step |in |management?
Answer: |Upper |endoscopy.
Rationale: |Melena |suggests |upper |GI |bleed, |requiring |endoscopic |evaluation.
14. Q14: |A |3-year-old |presents |with |a |barking |cough |and |inspiratory |stridor. |What |is |the |
most |likely |diagnosis?
