Internal Medicine

A 54-year-old man is evaluated in the intensive care unit on hospital day 3. He was initially admitted for community-acquired pneumonia and septic shock, requiring endotracheal intubation, mechanical ventilation, and vasopressor support. His empiric antibiotic regimen was de-escalated to intravenous ceftriaxone and oral azithromycin two days ago based on sputum cultures confirming *Streptococcus pneumoniae*.

Today, his blood pressure has improved to $115/75\text{ mm Hg}$ on a minimal weaning dose of norepinephrine, and his temperature is $37.4^\circ\text{C}$ ($99.3^\circ\text{F}$). He remains deeply sedated and is not initiating spontaneous breaths.

Current ventilator settings (Volume Assist-Control):
Tidal Volume: $450\text{ mL}$
Respiratory Rate: $12/\text{min}$
$\text{FiO}_2$: $0.35$
PEEP: $5\text{ cm H}_2\text{O}$

Which of the following are appropriate management steps for this patient? (Select all that apply)

A 67-year-old man is evaluated on hospital day 3. He was initially admitted for fever, chills, and left flank pain. His past medical history is significant for a T10 spinal cord injury resulting in neurogenic bladder, managed with intermittent clean catheterization. On presentation to the emergency department, his temperature was $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), blood pressure was $92/58\text{ mmHg}$, and heart rate was $114/\text{min}$. Laboratory testing demonstrated a leukocyte count of $16,500/\text{mm}^3$. He was aggressively resuscitated with intravenous fluids and empirically started on intravenous piperacillin-tazobactam and vancomycin for presumed urosepsis.

Today, the patient's temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure is $122/78\text{ mmHg}$, and heart rate is $82/\text{min}$. He has been afebrile for the last 36 hours and is tolerating a normal oral diet. His flank pain has resolved. The urine culture collected on admission has finalized, growing $>10^5\text{ CFU/mL}$ of *Enterococcus faecalis*. Susceptibility testing results are as follows:

Blood cultures drawn on admission show no growth after 48 hours. Which of the following is the most appropriate next step in the patient's antimicrobial management?

A $68$-year-old woman is evaluated on hospital day $3$. She was initially admitted to the intensive care unit with fever, right upper quadrant pain, jaundice, and hypotension. On admission, her temperature was $39.2^\circ\text{C}$ ($102.6^\circ\text{F}$), blood pressure was $88/54\text{ mmHg}$, and heart rate was $118\text{/min}$. Laboratory studies showed a leukocyte count of $18,500/\mu\text{L}$, total bilirubin of $6.2\text{ mg/dL}$, and alkaline phosphatase of $450\text{ U/L}$. She was resuscitated with intravenous fluids, started on empiric intravenous piperacillin-tazobactam, and underwent emergent endoscopic retrograde cholangiopancreatography (ERCP), which revealed purulent bile and a common bile duct stone. A biliary sphincterotomy with stone extraction was performed successfully.

Today, she is transferred to the general medical floor. She is afebrile and hemodynamically stable, and her abdominal pain has resolved. Blood cultures drawn on admission now grow *Escherichia coli*. Susceptibility testing demonstrates that the organism is resistant to ampicillin but susceptible to ceftriaxone, cefepime, ciprofloxacin, meropenem, and piperacillin-tazobactam.

Which of the following is the most appropriate next step in the pharmacotherapy of this patient?

A 62-year-old man arrives at the emergency department reporting the abrupt onset of severe, tearing chest pain radiating to his interscapular region. He appears diaphoretic and anxious. Vital signs show a heart rate of 118/min and blood pressure of 215/115 mm Hg in the right arm and 180/100 mm Hg in the left arm. Neurologic examination is unremarkable. Cardiac auscultation reveals an early diastolic decrescendo murmur at the right upper sternal border. Electrocardiogram demonstrates sinus tachycardia and criteria for left ventricular hypertrophy but no acute ischemic changes. Arrange the following interventions in the most appropriate chronological sequence for the management of this patient.

A $58$-year-old male is evaluated in the hospital on hospital day $3$. He was initially admitted for worsening abdominal distension, lethargy, and confusion. He has a past medical history of alcoholic cirrhosis and esophageal varices. On admission, his temperature was $37.8^\circ\text{C}$ ($100.0^\circ\text{F}$), blood pressure was $105/65\text{ mmHg}$, and pulse was $92/\text{min}$. Physical examination revealed scleral icterus, spider angiomas, a prominent fluid wave, and mild, diffuse abdominal tenderness. Laboratory studies on admission showed:

A diagnostic paracentesis yielded hazy fluid with a leukocyte count of $750/\text{mm}^3$ and $80\%$ polymorphonuclear cells. Due to a prolonged hospitalization for a variceal bleed one month prior, he was empirically started on intravenous piperacillin-tazobactam.

Today, his mental status has returned to baseline, and his abdominal discomfort has resolved. Ascitic fluid cultures from admission have grown *Escherichia coli*. Susceptibility testing shows the isolate is resistant to ciprofloxacin but sensitive to ceftriaxone, cefotaxime, piperacillin-tazobactam, and meropenem. Which of the following is the most appropriate next step in the pharmacologic management of this patient's infection?

A 74-year-old man is brought to the emergency department due to sudden-onset, severe abdominal pain that began 2 hours ago. He has a medical history of chronic obstructive pulmonary disease, heart failure with preserved ejection fraction, and paroxysmal atrial fibrillation. He recently stopped taking his prescribed apixaban. The patient reports nausea and one episode of vomiting. He also complains of mild shortness of breath. Temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure is $150/90 \text{ mmHg}$, pulse is $118\text{ /min}$ and irregularly irregular, and respirations are $22\text{ /min}$. Pulse oximetry is $94\%$ on room air. Lung auscultation reveals scattered end-expiratory wheezes. The abdomen is soft and non-distended; there is mild, diffuse tenderness to palpation, but no rebound or guarding. Bowel sounds are decreased. Laboratory studies show:

Leukocyte count: $16,500/\text{mm}^3$
Lactic acid: $3.8 \text{ mmol/L}$
Thyroid-stimulating hormone (TSH): $0.3 \mu\text{U/mL}$ (N: $0.4-4.0 \mu\text{U/mL}$)

Which of the following is the most appropriate next step in management?

A 58-year-old woman is evaluated in the outpatient clinic for a six-month history of progressive abdominal bloating, frequent flatulence, and chronic watery diarrhea. She also reports a 4.5-kg (10-lb) weight loss over this period despite maintaining a normal appetite. Her past medical history is notable for Raynaud phenomenon and systemic sclerosis, for which she is taking mycophenolate mofetil. Vital signs are within normal limits. Physical examination reveals thickened, tight skin over the fingers and face, as well as mild, diffuse abdominal distension without focal tenderness or organomegaly. Laboratory studies are obtained and reveal the following:

Hemoglobin: 10.4 g/dL
Mean corpuscular volume: 106 fL
Vitamin B12: 120 pg/mL (low)
Folate: 26 ng/mL (abnormally high)

Which of the following is the most appropriate next step in the diagnostic evaluation of this patient's gastrointestinal symptoms?

A 52-year-old man presents to the clinic reporting progressively worsening swelling in his lower extremities and profound daytime fatigue over the past four months. His wife, who accompanies him, notes that he frequently falls asleep during conversations and snores loudly at night. His medical history includes obesity, essential hypertension, and diet-controlled type 2 diabetes mellitus. He has no history of tobacco use.

Vital signs show a temperature of $36.8^\circ\text{C}$ ($98.2^\circ\text{F}$), heart rate of $88/\text{min}$, blood pressure of $135/85\text{ mmHg}$, respiratory rate of $14/\text{min}$, and oxygen saturation of $89\%$ on room air. BMI is $42\text{ kg/m}^2$.

Physical examination reveals prominent jugular venous distention with noticeable *a* waves. Cardiac auscultation demonstrates a right ventricular heave, a loud pulmonic component of the second heart sound ($P_2$), and a holosystolic murmur at the left lower sternal border that increases in intensity with inspiration. The lungs are clear to auscultation bilaterally. Bilateral $3+$ pitting edema is present up to the knees.

Laboratory studies show:
Hemoglobin: $16.8\text{ g/dL}$
Thyroid-stimulating hormone (TSH): $2.5\text{ \mu U/mL}$ (Normal: $0.4-4.0\text{ \mu U/mL}$)
Free T4: $1.2\text{ ng/dL}$ (Normal: $0.9-1.7\text{ ng/dL}$)

An arterial blood gas analysis obtained on room air reveals:
pH: $7.37$
$\text{PaCO}_2$: $56\text{ mmHg}$
$\text{PaO}_2$: $60\text{ mmHg}$
$\text{HCO}_3^-$: $31\text{ mEq/L}$

Which of the following is the most appropriate next step in the diagnostic evaluation or management of this patient?

A 56-year-old man is admitted to the hospital with a 2-day history of diffuse abdominal pain, nausea, and progressive lethargy. He has a history of alcohol-associated cirrhosis and portal hypertension. On presentation, his temperature is $38.2^\circ\text{C}$ ($100.8^\circ\text{F}$), blood pressure is $105/65\text{ mmHg}$, heart rate is $98/\text{min}$, and respiratory rate is $20/\text{min}$. Physical examination shows scleral icterus, spider angiomata, and moderate abdominal distension with shifting dullness. There is diffuse abdominal tenderness but no rebound or guarding. Bowel sounds are hypoactive. Asterixis is present. Arterial blood gas analysis on room air reveals the following:

Diagnostic paracentesis is performed, and ascitic fluid analysis shows:

Gram stain of the fluid shows no organisms.

Which of the following is the most appropriate next step in the management of this patient?

A $31$-year-old woman, G1P0, at $26$ weeks gestation is brought to the emergency department due to acute-onset severe shortness of breath, palpitations, and an episode of coughing up blood-tinged sputum. Her symptoms began abruptly $2$ hours ago. Over the past two months, she has experienced progressive fatigue and mild exertional dyspnea, which she attributed to her pregnancy. She emigrated from Southeast Asia five years ago and has not had consistent medical care. Her temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $108/68$ mmHg, heart rate is $145$/min and irregularly irregular, respiratory rate is $28$/min, and oxygen saturation is $89\%$ on room air. Jugular venous pressure is elevated. The apical impulse is not displaced. Cardiac auscultation reveals a loud first heart sound, an early diastolic high-frequency sound, and a low-pitched mid-diastolic rumble at the apex. Bilateral fine crackles are heard in the lower two-thirds of the lung fields.

Laboratory results are as follows:
- Hemoglobin: $11.2$ g/dL
- Leukocyte count: $10,500$/mm $^3$
- Thyroid-stimulating hormone (TSH): $0.3$ mIU/L
- Free T4: $1.2$ ng/dL

Electrocardiography shows absent P waves, irregularly irregular R-R intervals, and right axis deviation. Which of the following is the most appropriate initial pharmacological intervention for this patient?

A $22$-year-old woman with a history of type $1$ diabetes mellitus is brought to the emergency department by her roommate due to severe lethargy, nausea, and diffuse abdominal pain for the past day. She has been unable to tolerate oral intake following a recent upper respiratory infection. Her temperature is $37.8^\circ\text{C}$ ($100.0^\circ\text{F}$), blood pressure is $88/54\text{ mmHg}$, pulse is $128/\text{min}$, and respirations are $28/\text{min}$ with deep, sighing breaths. The patient appears clinically dehydrated with dry mucous membranes. Capillary blood glucose is $610\text{ mg/dL}$. Initial laboratory studies are as follows:

Serum sodium: $132\text{ mEq/L}$
Serum potassium: $3.1\text{ mEq/L}$
Serum chloride: $98\text{ mEq/L}$
Serum bicarbonate: $10\text{ mEq/L}$

Arterial blood gas shows a pH of $7.12$. Urinalysis is strongly positive for ketones.

Arrange the following management steps in the most appropriate chronological sequence for this patient.

A 42-year-old man presents to the emergency department complaining of sharp, severe chest pain that began yesterday. He states that the pain is significantly worse when he breathes deeply or lies flat on his back, but it improves when he sits up and leans forward. He reports having had a mild upper respiratory infection with a sore throat one week ago. His temperature is 37.6°C (99.7°F), blood pressure is 120/80 mm Hg, heart rate is 95/min, respiratory rate is 16/min, and oxygen saturation is 99% on room air. Auscultation of the chest reveals a high-pitched, scratchy, three-component sound heard best at the left lower sternal border. An electrocardiogram (ECG) is obtained and shows diffuse, concave-upward ST-segment elevations and PR-segment depressions across multiple leads. Which of the following is the most appropriate initial treatment for this patient?

A male patient, aged $58$, presents to the emergency department complaining of a $3$-day history of fever, chills, and severe left knee swelling. He has a past medical history significant for type $2$ diabetes mellitus but denies any recent falls or joint trauma. Initial vital signs reveal a temperature of $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), blood pressure of $110/70\text{ mm Hg}$, and heart rate of $112/\text{min}$. Physical examination highlights a warm, intensely erythematous, and exquisitely tender left knee with a noticeable effusion.

Arthrocentesis is performed, yielding frankly purulent synovial fluid with a leukocyte count of $85,000/\text{mm}^3$ ($90\%$ neutrophils). Blood and synovial fluid cultures are obtained, and he is empirically started on intravenous vancomycin and ceftriaxone before undergoing urgent arthroscopic lavage.

On hospital day $3$, the patient demonstrates clinical improvement and is currently afebrile. The microbiology laboratory reports that both the synovial fluid and blood cultures are growing *Staphylococcus aureus*. Susceptibility testing demonstrates that the isolate is resistant to penicillin but susceptible to oxacillin, cefazolin, and clindamycin. The patient's allergy profile notes a mild, non-pruritic maculopapular rash that occurred after taking amoxicillin during childhood; he has never experienced anaphylaxis, angioedema, or respiratory compromise associated with any medication.

Which of the following is the most appropriate antimicrobial regimen for this patient going forward?

A 72-year-old woman is brought to the emergency department by her family after sustaining a fall at home. Four weeks ago, she was evaluated at an urgent care clinic for progressive fatigue, a smooth, red tongue, and mild tingling in her feet. At that time, her hemoglobin was 9.2 g/dL, mean corpuscular volume was 115 fL, and a peripheral blood smear showed hypersegmented neutrophils. She was diagnosed with megaloblastic anemia and started on high-dose oral folic acid supplementation by the urgent care provider.

Today, her family reports that her fatigue has improved, but her unsteadiness and numbness have significantly worsened over the past two weeks, leading to her fall. She has a past medical history of Hashimoto thyroiditis and takes levothyroxine. She consumes a standard omnivorous diet.

Vital signs are within normal limits. Neurologic examination reveals decreased vibratory sensation and proprioception in the bilateral lower extremities. Her gait is markedly wide-based and ataxic. Romberg test is positive. Repeat laboratory studies today show a hemoglobin of 10.8 g/dL and a mean corpuscular volume of 102 fL.

Which of the following best explains the clinical course of this patient?

While undergoing induction chemotherapy for acute myeloid leukemia, a $54$-year-old male patient receives a transfusion of packed red blood cells due to a hemoglobin level of $6.8 \text{ g/dL}$. Approximately twenty minutes after the infusion begins, the patient acutely develops rigors, severe lower back pain, and a feeling of impending doom. Vital signs reveal a temperature of $39.4^\circ\text{C}$ ($102.9^\circ\text{F}$), blood pressure of $88/54 \text{ mmHg}$, heart rate of $122/\text{min}$, and respiratory rate of $24/\text{min}$. Urine collected from his catheter is noted to be dark and reddish-brown. Which of the following is the most appropriate initial step in the management of this patient?

For each of the following patient vignettes presenting with complex hematologic and oncologic abnormalities, match the clinical scenario to the most appropriate definitive diagnostic test or initial next step in management.

A $62$-year-old man is evaluated in the emergency department for worsening shortness of breath, lightheadedness, and profound fatigue over the past $3$ days. He has a history of advanced non-small cell lung cancer. His temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $88/70 \text{ mm Hg}$, pulse is $120/\text{min}$, and respirations are $24/\text{min}$. Pulse oximetry shows $94\%$ on room air. The patient appears dyspneic and anxious. Physical examination reveals jugular venous distention up to the angle of the mandible while sitting upright. Lungs are clear to auscultation bilaterally. Cardiac auscultation reveals distant heart sounds and tachycardia without murmurs. His systolic blood pressure drops by $15 \text{ mm Hg}$ during inspiration. Extremities are cool to the touch with faint peripheral pulses. An electrocardiogram displays sinus tachycardia with low voltage QRS complexes and beat-to-beat variation in the QRS axis. Which of the following is the most appropriate next step in the management of this patient?

A 65-year-old man is brought to the emergency department by his family due to a 2-day history of worsening confusion, extreme thirst, and frequent urination. He has a 12-year history of type 2 diabetes mellitus and takes metformin and sitagliptin. He recently recovered from a mild urinary tract infection.

Vital signs show a temperature of $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), heart rate of $112\text{/min}$, blood pressure of $100/60\text{ mmHg}$, and respiratory rate of $18\text{/min}$.

Physical examination reveals dry mucous membranes and poor skin turgor. He is somnolent but arousable.

Laboratory evaluation shows:

An intravenous line is established, and rapid fluid resuscitation with $0.9\%$ sodium chloride is initiated. Which of the following is the most appropriate next step in the pharmacological management of this patient?

A $31$-year-old male landscape architect seeks medical evaluation at a walk-in clinic in Rhode Island during mid-July. He describes a five-day history of low-grade fevers, profound fatigue, and a spreading skin lesion on his back. Yesterday, he began experiencing difficulty holding liquids in his mouth and noticed an inability to completely shut his right eye. Vital signs are temperature $37.8^\circ\text{C}$ ($100.0^\circ\text{F}$), blood pressure $122/78\text{ mmHg}$, pulse $74/\text{min}$, and respiratory rate $14/\text{min}$. Physical examination reveals a $12\text{ cm}$ annular, erythematous plaque with a distinct zone of central clearing on the right subscapular region. Neurologic examination demonstrates drooping of the right corner of the mouth, flattening of the right nasolabial fold, and an inability to close the right eyelid. Sensation to light touch on the face is intact. There is no nuchal rigidity, and the remainder of the examination is unremarkable. Which of the following is the most appropriate next step in management?

An evaluation is requested for a 68-year-old man who has developed severe anxiety, worsening palpitations, and a $4.5\text{-kg}$ ($10\text{-lb}$) unintentional weight loss over the past four weeks. He has a complex cardiovascular history including ischemic cardiomyopathy and recurrent ventricular tachycardia, which is currently managed with metoprolol, lisinopril, aspirin, and amiodarone. The amiodarone was initiated two years ago. Vital signs show a pulse of $112\text{/min}$ with an irregular rhythm, and blood pressure is $138/82\text{ mmHg}$. Physical examination reveals hyperreflexia, warm and moist skin, and a bilateral fine hand tremor. A non-tender, symmetrically enlarged thyroid gland is appreciated on palpation.

Recent laboratory results are as follows:

Which of the following is the most appropriate next step in the evaluation of this patient's current condition?