Internal Medicine

A 64-year-old man presents to the oncology clinic for an urgent evaluation due to a two-week history of profound fatigue, generalized weakness, and a persistent dull headache. He has metastatic melanoma and has been receiving immunotherapy with ipilimumab and nivolumab for the past three months. His temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $100/62\text{ mmHg}$, and pulse is $92/\text{min}$. Physical examination shows normal skin turgor and full visual fields to confrontation. There is no thyromegaly. Laboratory studies show:

* Serum sodium: $132\text{ mEq/L}$ (Normal: $136 - 145\text{ mEq/L}$)
* Serum potassium: $4.2\text{ mEq/L}$ (Normal: $3.5 - 5.0\text{ mEq/L}$)
* Thyroid-stimulating hormone (TSH): $0.2\text{ mU/L}$ (Normal: $0.5 - 5.0\text{ mU/L}$)
* Free thyroxine (T4): $0.4\text{ ng/dL}$ (Normal: $0.9 - 1.7\text{ ng/dL}$)

Which of the following is the most likely underlying mechanism for this patient's current endocrine abnormality?

A 54-year-old man presents to the urgent care clinic with a 2-day history of a red, warm, and tender rash on his right lower leg. The area has been progressively enlarging. He has a history of type 2 diabetes mellitus and hypertension. His temperature is $37.9^\circ\text{C}$ ($100.2^\circ\text{F}$), blood pressure is $128/82\text{ mm Hg}$, pulse is $88/\text{min}$, and respirations are $16/\text{min}$. Physical examination of the right lower extremity reveals a poorly demarcated, erythematous, warm, and tender area of skin extending from the ankle to the mid-calf. There is no fluctuance, purulent drainage, or palpable crepitus. Sensation to light touch is intact. His leukocyte count is $10,500/\text{mm}^3$. Which of the following is the most appropriate next step in pharmacotherapy?

A 52-year-old woman comes to the physician after noticing a lump in her lower neck 2 weeks ago. She also reports feeling more anxious than usual recently and has had occasional palpitations. She has no difficulty swallowing, hoarseness, or shortness of breath. Vital signs show a temperature of 37.1°C (98.8°F), blood pressure of 138/82 mm Hg, and pulse of 105/min. Physical examination reveals a 2.5-cm, firm, mobile, non-tender nodule in the right lobe of the thyroid gland. There is no cervical lymphadenopathy. Laboratory studies show:

Thyroid-stimulating hormone (TSH): 0.05 $\mu$ U/mL (Normal: 0.4–4.0 $\mu$ U/mL)
Free thyroxine (T4): 2.4 ng/dL (Normal: 0.8–1.8 ng/dL)

A thyroid ultrasound confirms a 2.6-cm solid, hypoechoic nodule in the right lobe with increased vascularity. Which of the following is the most appropriate next step in the evaluation of this patient?

Match each clinical presentation of a hereditary gastrointestinal polyposis or cancer syndrome with its corresponding underlying genetic mutation.

Paramedics transport a $34$-year-old male construction worker to the emergency department after he was trapped under a collapsed concrete wall for $6$ hours. En route to the hospital, he was administered $2$ mg of intravenous hydromorphone due to severe pain in his legs. Upon arrival, the patient appears lethargic and somnolent. Vital signs include a blood pressure of $110/70$ mm Hg, pulse of $112$/min, and respiratory rate of $10$/min. Physical examination reveals tense, swollen, and exquisitely tender bilateral lower extremities.

Laboratory results are as follows:

Arterial blood gas analysis on room air:

Based on the laboratory findings, which of the following best describes this patient's acid-base status?

A group of patients recently started various new antidiabetic therapies and subsequently developed medication-induced complications. Based on the distinct pharmacological profiles of these agents, match each antidiabetic medication to the clinical scenario that best describes its most characteristic adverse effect.

A $72$-year-old man is evaluated on postoperative day $2$ following an open sigmoid colectomy for recurrent complicated diverticulitis. The patient reports worsening shortness of breath that began this morning. His medical history is significant for chronic obstructive pulmonary disease and essential hypertension. His current medications include inhaled tiotropium and prophylactic subcutaneous enoxaparin. Temperature is $37.9^\circ\text{C}$ ($100.2^\circ\text{F}$), blood pressure is $138/82\text{ mm Hg}$, pulse is $112/\text{min}$, and respirations are $24/\text{min}$. Pulse oximetry shows an oxygen saturation of $88\%$ on room air. Jugular venous pressure is $6\text{ cm H}_2\text{O}$. Pulmonary auscultation reveals decreased breath sounds at the lung bases bilaterally without crackles or wheezes. Cardiac examination shows a regular tachycardia without murmurs. The surgical incision site is clean, dry, and intact. Arterial blood gas analysis on room air shows:

pH: $7.48$
$pCO_2$: $30\text{ mm Hg}$
$pO_2$: $58\text{ mm Hg}$
$HCO_3^-$: $22\text{ mEq/L}$

A chest radiograph reveals linear opacities at the bilateral lung bases with an unchanged cardiac silhouette and no pleural effusions. Which of the following is the most appropriate next action for this patient?

A 68-year-old woman is brought to the emergency department via ambulance due to the sudden onset of severe, "tearing" chest pain that radiates to between her shoulder blades. The pain started $45$ minutes ago while she was watching television. She has a history of poorly controlled essential hypertension and tobacco use. On arrival, she is visibly diaphoretic and in acute distress. Her blood pressure is $210/115 \text{ mm Hg}$ in the right arm and $175/95 \text{ mm Hg}$ in the left arm. Her heart rate is $112/\text{min}$, and her respiratory rate is $22/\text{min}$. Oxygen saturation is $96\%$ on room air. Physical examination reveals a new early diastolic decrescendo murmur auscultated best at the right upper sternal border. Neurologic examination is unremarkable. Two large-bore intravenous lines are established.

Arrange the following steps in the most appropriate chronological order for the evaluation and management of this patient.

Match each clinical presentation following a recent acute myocardial infarction with the most likely specific structural or inflammatory complication.

An inpatient consultation is requested for a 73-year-old male on the orthopedic surgery ward who developed acute-onset respiratory distress. The patient was admitted 3 days ago for management of right lower extremity cellulitis and has been receiving intravenous cefazolin and continuous normal saline at 125 mL/hr. Medical history is significant for hypertension, type 2 diabetes mellitus, and a 40-pack-year smoking history. Temperature is 37.1°C (98.8°F), blood pressure is 165/95 mm Hg, pulse is 112/min, and respirations are 28/min. Pulse oximetry shows 88% on room air. Physical examination reveals a patient in moderate respiratory distress using accessory muscles. Jugular venous pulsation is visible 11 cm above the sternal angle. Lung auscultation demonstrates diffuse, bilateral end-expiratory wheezes with scattered bibasilar crackles. Cardiac auscultation reveals a regular tachycardia with a prominent early diastolic extra heart sound. Lower extremities show 2+ pitting edema bilaterally extending to the knees. Which of the following is the most appropriate next step in management?

A 62-year-old woman is currently mechanically ventilated in the intensive care unit due to acute respiratory distress syndrome following a motor vehicle collision 6 days ago. Over the past 12 hours, her clinical status has deteriorated. She has developed a new fever of 38.9°C (102.0°F), her endotracheal secretions have become increasingly purulent, and her oxygen requirements have significantly increased. A portable chest radiograph demonstrates a new consolidation in the right lower lobe.

Arrange the following clinical steps in the most appropriate chronological order for the management of this patient's suspected infectious condition.

A $65$-year-old man is evaluated in the surgical intensive care unit on postoperative day $4$ following a partial colectomy for recurrent diverticulitis. Over the past $6$ hours, he has developed a fever, chills, and progressively worsening shortness of breath. His medical history is notable for severe chronic obstructive pulmonary disease (COPD) and a known bicuspid aortic valve.

Current vital signs are temperature $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), blood pressure $82/48\text{ mm Hg}$, pulse $126/\text{min}$ and regular, and respiratory rate $28/\text{min}$. Pulse oximetry shows $88\%$ on room air.

Physical examination reveals a diaphoretic man in acute respiratory distress. Jugular venous distention is present. Chest auscultation reveals diffuse bilateral crackles and scattered wheezes. Cardiac auscultation reveals a new, loud, grade $3/6$ decrescendo diastolic murmur heard best at the left sternal border.

His surgical incisions appear clean and intact. A central venous catheter, placed prior to surgery, remains in the right internal jugular vein, and the insertion site is erythematous and tender.

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

A $35$-year-old woman with a history of Sjögren syndrome comes to the clinic due to progressive generalized weakness and fatigue for the past month. Her blood pressure is $110/70$ mm Hg and her physical examination is unremarkable except for dry oral mucosa.

Laboratory studies show:
- Serum sodium: $140$ mEq/L
- Serum potassium: $2.8$ mEq/L
- Serum chloride: $115$ mEq/L
- Serum bicarbonate: $13$ mEq/L
- Urine sodium: $45$ mEq/L
- Urine potassium: $25$ mEq/L
- Urine chloride: $40$ mEq/L

The patient's serum anion gap is calculated to be $12$ mEq/L (normal: $10-14$ mEq/L), indicating a normal anion gap metabolic acidosis. To help determine whether the acidosis is due to renal or gastrointestinal etiology, what is this patient's calculated urine anion gap (in mEq/L)?

An 81-year-old male is currently receiving care in the intensive care unit for septic shock secondary to a complicated urinary tract infection. On his fourth day of admission, he remains intubated, though his vasopressor requirements have decreased over the last 24 hours. Routine laboratory testing is performed to evaluate a persistent sinus bradycardia. The results reveal a thyroid-stimulating hormone (TSH) level of $0.3 \, \mu\text{U/mL}$ (normal: $0.5-5.0 \, \mu\text{U/mL}$), a free thyroxine (T4) level of $0.7 \, \text{ng/dL}$ (normal: $0.9-2.4 \, \text{ng/dL}$), and a total triiodothyronine (T3) level of $42 \, \text{ng/dL}$ (normal: $80-200 \, \text{ng/dL}$). His core temperature is $36.2^\circ\text{C}$ ($97.2^\circ\text{F}$), blood pressure is $112/68 \, \text{mmHg}$ on low-dose norepinephrine, and heart rate is $58/\text{min}$. Which of the following is the most appropriate next step in the management of this patient's thyroid findings?

A 61-year-old woman is brought to the emergency department due to the sudden onset of severe shortness of breath and right-sided pleuritic chest pain that began 2 hours ago. She has no significant past medical history but underwent a total left hip arthroplasty 2 weeks ago. She admits to spending most of her time in bed since the surgery due to pain. Her temperature is 37.1°C (98.8°F), blood pressure is 114/72 mm Hg, pulse is 118/min, and respiratory rate is 26/min. Pulse oximetry shows 88% on room air. Physical examination reveals clear lungs bilaterally. Cardiac auscultation reveals a regular tachycardia with a prominent pulmonic component of the second heart sound. The left calf is mildly swollen and tender compared to the right. Arterial blood gas analysis on room air reveals the following:

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

A 68-year-old man is evaluated in the cardiac intensive care unit for sudden-onset severe dyspnea and lightheadedness. He was admitted 4 days ago for an acute inferior myocardial infarction, which was treated with prompt percutaneous coronary intervention of the right coronary artery. His temperature is 38.1°C (100.6°F), blood pressure is 78/50 mmHg, pulse is 122/min, and respirations are 24/min. Pulse oximetry shows 92% on 4 L/min by nasal cannula. Physical examination reveals jugular venous distension up to the angle of the mandible. Lung auscultation is completely clear bilaterally. Cardiac auscultation reveals a rapid rate and a new, harsh holosystolic murmur best heard at the left lower sternal border, accompanied by a palpable thrill. His extremities are cool and clammy. Which of the following is the most appropriate next step in management?

A 59-year-old man presents to the emergency department with sudden-onset, severe, "ripping" chest pain that radiates to his back, between the shoulder blades. His blood pressure is 198/112 mmHg in the right arm and 192/108 mmHg in the left arm. His heart rate is 118/min. Physical examination reveals a faint early diastolic decrescendo murmur at the right sternal border. Electrocardiogram shows sinus tachycardia with no ST-segment or T-wave abnormalities. Chest x-ray demonstrates a widened mediastinum. Arrange the following interventions in the most appropriate sequential order for the initial management of this patient.

Match each clinical exposure scenario with the most appropriate guideline-directed post-exposure prophylaxis (PEP) or preventative management.

A 22-year-old man with a history of type 1 diabetes mellitus is brought to the emergency department due to confusion, intractable vomiting, and diffuse abdominal pain. He reports missing his insulin doses for the past two days due to a gastrointestinal illness. His blood pressure is 90/60 mmHg, heart rate is 125/min, and respiratory rate is 28/min with deep, rapid breaths. Mucous membranes are extremely dry. Laboratory evaluation reveals a blood glucose of 580 mg/dL, an arterial pH of 7.15, serum bicarbonate of 12 mEq/L, an anion gap of 22 mEq/L, and a serum potassium of 4.8 mEq/L.

Arrange the following management steps in the correct chronological sequence for treating this patient's condition, from immediate resuscitation to resolution.

A $33$-year-old primigravida at $38$ weeks gestation presents to the obstetric triage unit with a $2$-week history of worsening fatigue, exertional dyspnea, and a persistent dry, nocturnal cough. The patient states she has recently started sleeping in a recliner chair because she feels "smothered" when lying flat in bed. Her pregnancy has been largely uncomplicated, with normal prenatal anatomy scans and glucose tolerance testing. She takes a daily prenatal vitamin. Temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $138/86\text{ mm Hg}$, pulse is $112/\text{min}$, and respirations are $22/\text{min}$. Pulse oximetry is $94\%$ on room air. Physical examination reveals jugular venous distention $8\text{ cm}$ above the sternal angle when sitting at $45$ degrees. Cardiac auscultation demonstrates a regular tachycardia and a low-frequency, early diastolic sound heard best at the apex in the left lateral decubitus position. Lung auscultation reveals fine bibasilar crackles. Bilateral $2+$ pitting pedal edema is present. Fetal heart rate monitoring shows a baseline of $145/\text{min}$ with moderate variability and positive accelerations. Which of the following is the most appropriate next step in the management of this patient?