Cardio!
A 3-month-old infant is brought in for poor feeding and failure to thrive. The mother reports sweating during feeds. On exam:
Tachypnea and subcostal retractions
A harsh holosystolic murmur best heard at the lower left sternal border
Hepatomegaly
Echocardiography shows increased pulmonary blood flow and enlargement of the left atrium and left ventricle.
Diagnosis?
Ventricular Septal Defect
Holosystolic murmur at LLSB
Left → right shunt → ↑ pulmonary flow → LA/LV enlargement
CHF symptoms in infancy (sweating with feeds)
A 60-year-old man with a long smoking history presents with fatigue and confusion.
Labs:
Sodium: 118 mEq/L (nl: 135-145)
Serum osmolality: low
Urine osmolality: high
Chest imaging reveals a centrally located lung mass.
Further testing shows ectopic hormone production leading to inappropriate water retention.
Diagnosis?
Small Cell Lung Carcinoma (SIADH)
A 14-year-old boy presents with persistent microscopic hematuria. Family history reveals male relatives with kidney disease. He also has difficulty hearing in school.
Renal biopsy:
Diagnosis?
Alport Syndrome
A 32-year-old man presents after a knife injury to his back. On exam, he has:
Where is the spinal cord lesion?
Right spinothalamic tract
Loss of pain and temperature only → spinothalamic
Decussates almost immediately in anterior white commisure → contralateral loss
A 68-year-old man with a history of myocardial infarction presents with palpitations and lightheadedness. ECG shows monomorphic ventricular tachycardia. He is started on a medication that blocks potassium channels in depolarized ventricular tissue and also has beta-blocking properties. After starting therapy, he develops pulmonary fibrosis and hypothyroidism.
Name the drug
Amiodarone
A 72-year-old woman with long-standing hypertension presents with dyspnea on exertion.
Exam shows bibasilar crackles, S4 heart sound, but no peripheral edema.
Echocardiogram shows normal ejection fraction concentric left ventricular hypertrophy, impaired ventricular relaxation.
Diagnosis?
Diastolic Heart Failure
Normal EF + impaired relaxation
Long-standing HTN → stiff ventricle
S4 = atrial kick into noncompliant LV
A 63-year-old woman presents with fever and cough. She has mild confusion.
Physiologic assessment shows areas of lung receiving perfusion but minimal ventilation. Supplemental oxygen improves her oxygenation.
Chest imaging demonstrates a focal region of increased density confined to a single lobe.
Diagnosis?
Lobar pneumonia
A 7-year-old boy is brought in for facial swelling and decreased urine output. Two weeks earlier, he had a febrile illness with sore throat. Labs show:
Renal biopsy:
Diagnosis?
Post-Streptococcal Glomerulonephritis (PSGN)
A 58-year-old man presents with progressive weakness. Exam shows:
Where is the spinal cord lesion?
Right corticospinal tract
Spastic paralysis + Babinski → upper motor neuron → corticospinal tract
Decussates in the medulla → ipsilateral weakness below the crossing
A 52-year-old man with a history of COPD presents with progressive dyspnea and chronic cough. Pulmonary function tests show decreased FEV₁/FVC ratio with minimal reversibility after bronchodilator administration. He is started on a medication for maintenance therapy.
Several weeks later, he reports dry mouth and mild urinary retention. His symptoms improve significantly, but he is told the medication is particularly effective in his condition due to increased vagal tone–mediated bronchoconstriction.
Which drug was most likely prescribed?
Tiotropium
M3 receptor → Gq → ↑ IP₃ → ↑ Ca²⁺ → bronchoconstriction
Blocking M3 → bronchodilation
A 58-year-old man presents with exertional chest pain and syncope.
On exam:
Harsh crescendo-decrescendo systolic murmur at the right upper sternal border
Murmur radiates to the carotids
Decreased and delayed carotid upstroke
Diagnosis?
Aortic Stenosis
A 28-year-old man involved in a motor vehicle collision becomes acutely dyspneic shortly after arrival.
Vitals reveal hypotension and tachycardia.
On exam, there is markedly reduced breath sounds on one side. Shortly after, he develops worsening hypotension.
Cardiac output is decreased due to impaired venous return.
Diagnosis?
Tension pneumothorax
A 52-year-old man presents with rapidly worsening renal function over 2 weeks. He reports fatigue and decreased urine output. Labs show hematuria with RBC casts, mild proteinuria, and elevated creatinine. Serology is negative for anti-GBM and ANCA antibodies.
Renal biopsy:
Diagnosis?
Rapidly progressive glomerulonephritis (RPGN)
A 45-year-old woman presents with sensory changes. On exam, she has:
Where is the spinal cord lesion?
Left fasciculus cuneatus
Loss of vibration & proprioception only → dorsal column medial lemniscus pathway
Upper extremity only → cuneatus (arms)
Ipsilateral deficit → lesion before decussation (spinal cord)
A 70-year-old patient with advanced heart failure and sulfa allergy is treated with a loop diuretic. He develops profound hypokalemia, metabolic alkalosis, and sudden hearing loss after dose escalation.
Name the drug
Ethacrynic acid
Only loop diuretic that is non-sulfonamide
Acts on Na⁺-K⁺-2Cl⁻ cotransporter in thick ascending limb
Used in sulfa-allergic patients
Toxicity:
A 35-year-old man presents with sharp chest pain that worsens when lying flat and improves when leaning forward.
Physical exam reveals a scratchy, high-pitched sound best heard at the left lower sternal border and diffuse ST elevations and PR depressions on ECG.
Diagnosis?
Acute pericarditis
A 46-year-old man is admitted for severe pancreatitis. On hospital day 3, he develops progressive shortness of breath.
Vitals: RR 30/min, SpO₂ 84% on 6 L nasal cannula
ABG: PaO₂- 55 mmHg (nl: 80-100), PaCO₂- 32 mmHg (nl: 35-45)
Chest imaging shows diffuse bilateral opacities. Cardiac catheterization reveals normal left atrial pressure.
Despite increasing inspired oxygen concentration, his arterial oxygenation shows minimal improvement.
Diagnosis?
ARDS
A 24-year-old woman presents with fatigue, joint pain, and facial rash. Labs show hematuria, proteinuria, low C3 and low C4 and positive anti–double-stranded DNA antibodies.
Renal biopsy:
Diagnosis?
Diffuse proliferative glomerulonephritis (DPGN)
A 25-year-old man presents after a spinal cord injury. On exam, he has:
Where is the spinal cord lesion?
Left ventral horn
Flaccid paralysis + atrophy → lower motor neuron
LMNs → ventral horns
Left side deficit (ipsilateral lesion) → left ventral horn
A 71-year-old man with type 2 diabetes presents with confusion and diaphoresis. His wife reports that over the past week he has had several episodes of dizziness, especially in the early morning before breakfast. His medications include a recently started oral antihyperglycemic agent.
Past medical history is significant for:
Labs:
He is treated with IV dextrose, but several hours later, he again becomes hypoglycemic.
Which medication is most likely responsible, and why is it contraindicated in this patient?
Glyburide
MOA:
Close ATP-sensitive K⁺ channels in β-cells → ↑ insulin release (glucose-independent)
Produces active metabolites cleared by the kidneys → accumulation in CKD → prolonged hypoglycemia
A 69-year-old man presents with fatigue.
Continuous rhythm monitoring shows highly variable R-R intervals, absence of coordinated atrial contraction, and reduced ventricular filling efficiency.
The patient is diagnosed with atrial fibrillation. What structure causes an increased risk of thromboembolic stroke in this patient?
Left atrial appendage
A 41-year-old woman with progressive exertional dyspnea undergoes right heart catheterization showing elevated pulmonary arterial pressures with normal left-sided pressures.
She is started on a medication that increases intracellular cyclic GMP in vascular smooth muscle, leading to selective pulmonary vasodilation.
She is advised to avoid taking nitrates due to risk of severe hypotension.
What drug class/medication is this patient on?
Sildenafil (PDE5 inhibitor)
A 19-year-old man presents with edema and dark urine. He has a history of intravenous drug use. Labs show mild proteinuria and hematuria, low C3 with normal C4, and elevated creatinine.
Renal biopsy:
Diagnosis?
Membranoproliferative glomerulonephritis (MPGN)
A 67-year-old man presents with progressive difficulty walking. He reports that he “can’t tell where his feet are” unless he looks at them. On exam:
Where are the spinal cord lesions?
Left fasciculus gracilis (DCML) and right spinothalamic tract
Loss of vibration and proprioception → Dorsal Column Medial Lemniscus
Left lower extremity loss (ipsilateral) → left fasciculus gracilis
Loss of pain & temperature → Spinothalamic tract
Left sided pain and temp loss (contralateral) → right spinothalamic tract
A 64-year-old man with hypertension and HFrEF is started on combination therapy. Two weeks later, his labs show:
Blood pressure is well controlled.
Further testing shows:
A second medication is added to improve mortality, but shortly after, his potassium rises further to 6.5 mEq/L. He reports breast tenderness and decreased libido.
Which combination of drugs is most likely responsible for this patient’s findings?
ACE inhibitor/ARB + Spironolactone
Blocks Ang I → Ang II
↓ aldosterone → ↓ K⁺ excretion → hyperkalemia
Loss of Ang II feedback → ↑ renin
Gynecomastia + decreased libido → Strongly points to a Spironolactone (Mineralocorticoid receptor antagonist)
Leads to ↓ aldosterone signaling, ↓ K⁺ secretion in collecting duct → severe hyperkalemia