DIAGNOSTIC REASONING REAL EXAM REVIEW 150 QUESTIONS AND
CORRECT ANSWERS WITH RATIONALES COVERING THE MOST TESTED
QUESTIONS RELIABLE FOR A+ GRADE
1. A 45-year-old male presents with chest pain radiating to the left arm and jaw. What is the
most likely diagnosis?
A) Gastroesophageal reflux disease
B) Acute myocardial infarction
C) Costochondritis
D) Panic attack
Rationale: Radiating chest pain with cardiac risk factors is classic for myocardial infarction.
2. A patient presents with polyuria, polydipsia, and weight loss. Which test best confirms your
suspected diagnosis?
A) Complete blood count
B) Fasting blood glucose
C) Serum calcium
D) Electrolyte panel
Rationale: Elevated fasting glucose confirms diabetes mellitus.
3. A 26-year-old woman presents with right lower quadrant pain, nausea, and fever. Which is
the most likely diagnosis?
A) Cholecystitis
B) Appendicitis
C) Diverticulitis
D) Ovarian cyst rupture
Rationale: Classic presentation for appendicitis includes RLQ pain with fever and nausea.
4. A patient with COPD complains of worsening shortness of breath and increased sputum.
What is the likely cause?
A) Acute exacerbation of COPD
B) Pulmonary embolism
C) Pneumothorax
D) Heart failure
Rationale: Increased sputum and dyspnea suggest an acute infectious or inflammatory flare-up.
,5. A 60-year-old woman presents with tremor, rigidity, and bradykinesia. What is the most
probable diagnosis?
A) Multiple sclerosis
B) Parkinson’s disease
C) Essential tremor
D) Stroke
Rationale: These are hallmark signs of Parkinson’s due to dopaminergic neuron loss.
6. A 23-year-old male presents with dysuria and urethral discharge. What test should be
ordered first?
A) CBC
B) Urine nucleic acid amplification test (NAAT)
C) Urinalysis
D) Blood culture
Rationale: NAAT is the gold standard for detecting gonorrhea and chlamydia.
7. A 70-year-old presents with confusion, hyponatremia, and small cell lung cancer. What is the
likely cause?
A) SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion)
B) Diabetes insipidus
C) Dehydration
D) Renal failure
Rationale: SIADH causes water retention and dilutional hyponatremia, often linked to small cell
carcinoma.
8. A 35-year-old woman has butterfly facial rash, fatigue, and joint pain. What is the likely
diagnosis?
A) Rheumatoid arthritis
B) Systemic lupus erythematosus (SLE)
C) Dermatomyositis
D) Rosacea
Rationale: The malar rash with joint pain is classic for SLE.
9. A patient with severe sore throat, drooling, and muffled voice is likely suffering from:
A) Strep pharyngitis
B) Epiglottitis
, C) Peritonsillar abscess
D) Laryngitis
Rationale: Drooling and airway obstruction signs indicate epiglottitis, a medical emergency.
10. A 50-year-old with chronic alcohol use presents with confusion, ataxia, and nystagmus.
What deficiency is likely?
A) Vitamin B12
B) Thiamine (Vitamin B1)
C) Folate
D) Niacin
Rationale: Thiamine deficiency causes Wernicke’s encephalopathy.
11. A 30-year-old man presents with hematuria after a sore throat two weeks ago. Most likely
diagnosis?
A) Post-streptococcal glomerulonephritis
B) Kidney stones
C) UTI
D) IgA nephropathy
Rationale: Hematuria following strep infection is classic for post-streptococcal GN.
12. Which finding supports a diagnosis of bacterial meningitis?
A) Clear CSF with normal glucose
B) Cloudy CSF, high protein, low glucose
C) High RBC count
D) Clear CSF, high glucose
Rationale: Bacterial meningitis lowers CSF glucose and raises protein.
13. A diabetic patient presents with foot ulcer and fever. Which is the next best step?
A) Apply topical cream
B) Order wound culture and start antibiotics
C) Dress wound only
D) Refer to podiatrist later
Rationale: Infected ulcers require prompt antibiotics and culture to prevent sepsis.
CORRECT ANSWERS WITH RATIONALES COVERING THE MOST TESTED
QUESTIONS RELIABLE FOR A+ GRADE
1. A 45-year-old male presents with chest pain radiating to the left arm and jaw. What is the
most likely diagnosis?
A) Gastroesophageal reflux disease
B) Acute myocardial infarction
C) Costochondritis
D) Panic attack
Rationale: Radiating chest pain with cardiac risk factors is classic for myocardial infarction.
2. A patient presents with polyuria, polydipsia, and weight loss. Which test best confirms your
suspected diagnosis?
A) Complete blood count
B) Fasting blood glucose
C) Serum calcium
D) Electrolyte panel
Rationale: Elevated fasting glucose confirms diabetes mellitus.
3. A 26-year-old woman presents with right lower quadrant pain, nausea, and fever. Which is
the most likely diagnosis?
A) Cholecystitis
B) Appendicitis
C) Diverticulitis
D) Ovarian cyst rupture
Rationale: Classic presentation for appendicitis includes RLQ pain with fever and nausea.
4. A patient with COPD complains of worsening shortness of breath and increased sputum.
What is the likely cause?
A) Acute exacerbation of COPD
B) Pulmonary embolism
C) Pneumothorax
D) Heart failure
Rationale: Increased sputum and dyspnea suggest an acute infectious or inflammatory flare-up.
,5. A 60-year-old woman presents with tremor, rigidity, and bradykinesia. What is the most
probable diagnosis?
A) Multiple sclerosis
B) Parkinson’s disease
C) Essential tremor
D) Stroke
Rationale: These are hallmark signs of Parkinson’s due to dopaminergic neuron loss.
6. A 23-year-old male presents with dysuria and urethral discharge. What test should be
ordered first?
A) CBC
B) Urine nucleic acid amplification test (NAAT)
C) Urinalysis
D) Blood culture
Rationale: NAAT is the gold standard for detecting gonorrhea and chlamydia.
7. A 70-year-old presents with confusion, hyponatremia, and small cell lung cancer. What is the
likely cause?
A) SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion)
B) Diabetes insipidus
C) Dehydration
D) Renal failure
Rationale: SIADH causes water retention and dilutional hyponatremia, often linked to small cell
carcinoma.
8. A 35-year-old woman has butterfly facial rash, fatigue, and joint pain. What is the likely
diagnosis?
A) Rheumatoid arthritis
B) Systemic lupus erythematosus (SLE)
C) Dermatomyositis
D) Rosacea
Rationale: The malar rash with joint pain is classic for SLE.
9. A patient with severe sore throat, drooling, and muffled voice is likely suffering from:
A) Strep pharyngitis
B) Epiglottitis
, C) Peritonsillar abscess
D) Laryngitis
Rationale: Drooling and airway obstruction signs indicate epiglottitis, a medical emergency.
10. A 50-year-old with chronic alcohol use presents with confusion, ataxia, and nystagmus.
What deficiency is likely?
A) Vitamin B12
B) Thiamine (Vitamin B1)
C) Folate
D) Niacin
Rationale: Thiamine deficiency causes Wernicke’s encephalopathy.
11. A 30-year-old man presents with hematuria after a sore throat two weeks ago. Most likely
diagnosis?
A) Post-streptococcal glomerulonephritis
B) Kidney stones
C) UTI
D) IgA nephropathy
Rationale: Hematuria following strep infection is classic for post-streptococcal GN.
12. Which finding supports a diagnosis of bacterial meningitis?
A) Clear CSF with normal glucose
B) Cloudy CSF, high protein, low glucose
C) High RBC count
D) Clear CSF, high glucose
Rationale: Bacterial meningitis lowers CSF glucose and raises protein.
13. A diabetic patient presents with foot ulcer and fever. Which is the next best step?
A) Apply topical cream
B) Order wound culture and start antibiotics
C) Dress wound only
D) Refer to podiatrist later
Rationale: Infected ulcers require prompt antibiotics and culture to prevent sepsis.
