Internal Medicine

A $68$-year-old man is evaluated in the hospital for new-onset diarrhea. He was admitted $8$ days ago for a chronic obstructive pulmonary disease (COPD) exacerbation and was treated with a $5$-day course of systemic glucocorticoids and levofloxacin. Over the last $48$ hours, he has had $6$ to $8$ watery bowel movements daily, accompanied by lower abdominal cramping and low-grade fever. Vitals: T $37.9^\circ\text{C}$ ($100.2^\circ\text{F}$), HR $92/\text{min}$, BP $118/76 \text{ mmHg}$. Physical examination reveals mild, diffuse abdominal tenderness with normal bowel sounds; there is no rebound tenderness or guarding. Laboratory studies show a leukocyte count of $16,500/\text{mm}^3$ and serum creatinine of $1.1 \text{ mg/dL}$ (baseline $0.9 \text{ mg/dL}$). Stool enzyme immunoassay is positive for *Clostridioides difficile* glutamate dehydrogenase antigen and toxins A and B. Which of the following is the most appropriate next step in management?

A $61$-year-old woman is transferred to the intensive care unit following endotracheal intubation for acute-on-chronic hypercapnic respiratory failure. She has a $45$-pack-year smoking history and severe chronic obstructive pulmonary disease. For the past three days, she has experienced progressive dyspnea, a severe productive cough with purulent sputum, and profound fatigue. Upon arrival at the emergency department, she was somnolent, and an arterial blood gas analysis revealed a pH of $7.22$, a PaCO $_2$ of $82\text{ mm Hg}$, and a PaO $_2$ of $56\text{ mm Hg}$ on room air. After a failed trial of non-invasive positive pressure ventilation, she was intubated.

Currently, her temperature is $37.6^\circ\text{C}$ ($99.7^\circ\text{F}$), pulse is $112\text{/min}$, blood pressure is $138/88\text{ mm Hg}$, and oxygen saturation is $94\%$ on a fraction of inspired oxygen (FiO $_2$) of $0.40$. Physical examination reveals a barrel-shaped chest with diffuse, bilateral end-expiratory wheezing and a prolonged expiratory phase. Cardiac auscultation reveals a rapid, regular rhythm without murmurs or gallops. There is no jugular venous distention or peripheral edema. Chest radiograph demonstrates hyperinflated lungs with flattened diaphragms, but no focal consolidations or pleural effusions.

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

A 32-year-old woman presents to the emergency department complaining of sudden-onset, rapid heart palpitations and mild chest fullness that began 30 minutes ago while sitting at her desk. She denies syncope, severe shortness of breath, or chest pain. Her blood pressure is 115/75 mm Hg, pulse is 185/min, and respiratory rate is 16/min. Physical examination reveals regular, rapid heart sounds with no murmurs. An electrocardiogram demonstrates a regular, narrow-complex tachycardia with no discernible P waves.

Arrange the following interventions in the most appropriate sequential order for managing this patient's arrhythmia, assuming each preceding step fails to restore sinus rhythm.

Paramedics bring a 52-year-old unhoused man to the emergency department after he was found unresponsive in an alleyway during the winter. He has a known history of alcohol use disorder. On examination, he is obtunded and tachypneic.

Vital signs include a heart rate of $105/\text{min}$, blood pressure of $115/75 \text{ mmHg}$, and respiratory rate of $24/\text{min}$.

Laboratory studies reveal the following:

Arterial blood gas on room air shows a pH of $7.25$, $\text{pCO}_2$ of $28 \text{ mmHg}$, and $\text{pO}_2$ of $95 \text{ mmHg}$.

Based on the laboratory results provided, what is this patient's calculated serum osmolar gap in $\text{mOsm/kg}$?

A $22$-year-old man with a history of type 1 diabetes mellitus is brought to the emergency department due to severe abdominal pain, nausea, vomiting, and increasing lethargy over the past $24$ hours. His vital signs show a temperature of $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure of $90/60\text{ mm Hg}$, pulse of $122/\text{min}$, and respirations of $28/\text{min}$ with deep, sighing breaths. Physical examination reveals dry mucous membranes and poor skin turgor. Laboratory evaluation reveals the following:

Arrange the following management steps in the correct, priority-based chronological order for this patient.

A 54-year-old woman with a history of metastatic breast cancer is brought to the emergency department due to progressive, severe dyspnea and lightheadedness over the last 48 hours. She is diaphoretic and tachypneic. Vital signs show a temperature of 37.1°C (98.8°F), blood pressure of 82/52 mm Hg (which decreases to 68/46 mm Hg during inspiration), heart rate of 122/min, and respiratory rate of 26/min. Physical examination reveals jugular venous distention to the angle of the mandible while sitting at a 45-degree angle. Heart sounds are distant. Lungs are clear to auscultation bilaterally. Electrocardiography demonstrates sinus tachycardia with low QRS voltage and beat-to-beat variation in the QRS complex amplitude. Arrange the following management steps in the most appropriate chronological sequence for this patient's acute presentation.

A $42$-year-old man presents to a busy urgent care clinic with a $5$-week history of worsening cough producing blood-tinged sputum, drenching night sweats, and an $8$-kg ($17.6$-lb) weight loss. He immigrated to the United States from a highly endemic region $3$ years ago. His temperature is $38.3^\circ\text{C}$ ($100.9^\circ\text{F}$), blood pressure is $118/76\text{ mm Hg}$, pulse is $88\text{/min}$, and respiratory rate is $18\text{/min}$. He is currently seated in the crowded main waiting room.

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

A 68-year-old man is brought to the emergency department due to worsening shortness of breath, a productive cough, and progressive lethargy over the past 3 days. He has a history of severe chronic obstructive pulmonary disease (COPD) and heart failure with a reduced ejection fraction. One week ago, his primary care physician doubled his daily dose of oral furosemide due to increased lower extremity edema. On physical examination, his temperature is 37.2°C (99.0°F), blood pressure is 110/70 mm Hg, pulse is 98/min, and respiratory rate is 14/min. He is somnolent but arousable. Lung auscultation reveals diffuse expiratory wheezes and prolonged expiration. There is no lower extremity edema.

Arterial blood gas on room air:
pH: 7.37
$pCO_2$: 80 mm Hg
$pO_2$: 55 mm Hg

Serum chemistry:
Sodium: 137 mEq/L
Potassium: 2.9 mEq/L
Chloride: 80 mEq/L
Bicarbonate: 45 mEq/L

Which of the following best describes this patient's acid-base disorder?

A 24-year-old woman comes to the clinic for a routine health maintenance examination. She reports feeling well overall, though she notes occasional mild palpitations when she consumes excessive caffeine. She has no history of weight loss, heat intolerance, changes in bowel habits, or tremors. Four months ago, she was prescribed a combined oral contraceptive pill. Her only other medication is a daily multivitamin. Vital signs are within normal limits, with a pulse of $74/\text{min}$ and a blood pressure of $118/76\text{ mmHg}$. Physical examination reveals a normal-sized thyroid gland without palpable nodules. Deep tendon reflexes are $2+$ bilaterally. Laboratory studies show the following:

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

Match each classic cardiac auscultation finding with the valvular pathology it most accurately describes.

An $82$-year-old man is evaluated on postoperative day $2$ following an elective right total hip arthroplasty due to the sudden onset of shortness of breath and mild agitation. His medical history is significant for a $35$-pack-year smoking history with known chronic obstructive pulmonary disease (COPD), major depressive disorder managed with citalopram, and diet-controlled type 2 diabetes mellitus. His temperature is $37.6^\circ\text{C}$ ($99.7^\circ\text{F}$), blood pressure is $168/94\text{ mmHg}$, heart rate is $114/\text{min}$, and respiratory rate is $26/\text{min}$. Pulse oximetry shows $87\%$ on room air. Physical examination reveals an elevated jugular venous pressure of $11\text{ cm H}_2\text{O}$. Cardiac auscultation reveals a regular tachycardia with a prominent S3 gallop. Lung auscultation demonstrates diffuse, bilateral expiratory wheezes. The surgical incision is clean and intact. The lower extremities exhibit 2+ bilateral pitting edema. Initial laboratory studies show a normal complete blood count and a basic metabolic panel within normal limits. Thyroid studies reveal a thyroid-stimulating hormone (TSH) level of $1.4\text{ }\mu\text{U/mL}$ (normal: $0.4-4.0\text{ }\mu\text{U/mL}$) and a free T4 level of $0.6\text{ ng/dL}$ (normal: $0.9-1.7\text{ ng/dL}$). Which of the following is the most appropriate next step in the management of this patient?

Following 4 days of profuse, watery diarrhea, a 70-year-old man with a long-standing history of severe chronic obstructive pulmonary disease presents to the emergency department for evaluation of extreme weakness. He reports having 8 to 10 bowel movements daily since attending a family picnic. His home medications include a long-acting muscarinic antagonist and an inhaled corticosteroid.

Vital signs show a temperature of $37.4^\circ\text{C}$ ($99.3^\circ\text{F}$), blood pressure of 102/64 mm Hg, pulse of 115/min, and respiratory rate of 14/min. Physical examination reveals dry mucous membranes, decreased skin turgor, and diffuse expiratory wheezes bilaterally.

Laboratory studies are obtained:

Arterial blood gas on room air:

Which of the following best describes this patient's primary acid-base disturbance?

An independent $72$-year-old male presents to the acute care clinic with a $6$-hour history of severe, crampy left-sided abdominal pain and two episodes of bright red blood per rectum. Over the preceding three days, he experienced a viral gastroenteritis characterized by frequent watery stools and poor oral intake, which caused him to feel lightheaded upon standing. His past medical history includes heart failure with preserved ejection fraction, hypertension, and hyperlipidemia. His current medications are lisinopril, metoprolol, and atorvastatin.

Vital signs are heart rate $112\text{/min}$, blood pressure $105/65\text{ mm Hg}$, respiratory rate $18\text{/min}$, and oxygen saturation $96\%$ on room air. Physical examination shows dry mucous membranes and decreased skin turgor. The abdomen is soft but moderately tender to palpation in the left lower quadrant. There is no rebound tenderness, rigidity, or guarding. Bowel sounds are diminished.

Laboratory studies show:
Leukocyte count: $10,500\text{/mm}^3$
Hemoglobin: $14.2\text{ g/dL}$
Creatinine: $1.4\text{ mg/dL}$ (baseline $0.9\text{ mg/dL}$)
Lactic acid: $1.6\text{ mmol/L}$ (normal: $0.5-2.2\text{ mmol/L}$)

A CT scan of the abdomen with intravenous contrast reveals edema and thickening of the colonic wall isolated to the splenic flexure and descending colon. There is no evidence of pneumatosis intestinalis or free intraperitoneal air.

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

Match each clinical presentation of suspected adrenal or pituitary pathology with the most appropriate initial diagnostic or screening test.

Match each clinical presentation and urinalysis finding with the most likely underlying renal pathology.

A $34$-year-old man comes to the clinic due to a $2$-week history of right upper quadrant abdominal pain, fever, and significant fatigue. He returned from a $6$-month backpacking trip across Southeast Asia and India approximately $1$ month ago. During his trip, he experienced an episode of severe, bloody diarrhea that resolved after $5$ days with over-the-counter oral rehydration. His temperature is $38.7^\circ\text{C}$ ($101.7^\circ\text{F}$), pulse is $102/\text{min}$, and blood pressure is $118/76\text{ mm Hg}$. Physical examination reveals a moderately enlarged liver with marked point tenderness to palpation in the right subcostal region. There is no scleral icterus.

An abdominal ultrasound reveals a solitary, $7\text{-cm}$, round, hypoechoic cystic lesion in the right hepatic lobe with no internal septations.

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

A $29$-year-old man comes to the outpatient clinic due to a painful swelling on his right thigh. He first noticed a "pimple" in the area $4$ days ago, which has progressively enlarged and become increasingly tender. He has no significant past medical history and takes no medications. Vital signs show a temperature of $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure of $122/78$ mm Hg, and heart rate of $76$/min. Physical examination of the anterior right thigh reveals a $4$-cm, erythematous, exquisitely tender, and fluctuant mass. There is a $0.5$-cm rim of surrounding erythema. No induration extending beyond the erythema is noted, and there is no inguinal lymphadenopathy. Which of the following is the most appropriate next step in management?

Match each clinical presentation of a hypotensive patient with their most likely corresponding hemodynamic profile obtained via pulmonary artery catheterization. The parameters include central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), cardiac index (CI), and systemic vascular resistance (SVR).

A 55-year-old man is brought to the emergency department via ambulance after coughing up approximately 400 mL of bright red blood over the past hour. He has a history of treated pulmonary tuberculosis with residual cavitary disease in the right upper lobe. On arrival, he is in moderate respiratory distress and actively coughing up blood. Temperature is 37.1°C (98.8°F), blood pressure is 110/70 mm Hg, pulse is 118/min, and respirations are 28/min. Pulse oximetry shows an oxygen saturation of 86% on room air. Pulmonary auscultation reveals coarse rhonchi and gurgling over the right lung fields, with clear breath sounds over the left lung.

Arrange the following steps in the most appropriate sequential order for the acute management of this patient's massive hemoptysis.

A 58-year-old man presents to the clinic with progressive abdominal swelling, lower extremity edema, and exertional fatigue over the past 4 months. He has a history of Hodgkin lymphoma, for which he received mantle field radiation therapy 20 years ago. He has no history of tobacco or alcohol use. Vital signs are within normal limits. Physical examination shows marked jugular venous distension; the jugular venous pressure paradoxically increases during inspiration. Lung fields are clear to auscultation bilaterally. Cardiac auscultation reveals a regular rhythm and a high-pitched, early diastolic sound at the left sternal border. The abdomen is distended with a positive fluid wave, and the liver edge is palpable 4 cm below the right costal margin. Bilateral lower extremities demonstrate 2+ pitting edema up to the knees. An electrocardiogram reveals low-voltage QRS complexes in the limb leads. Which of the following is the most likely primary mechanism underlying this patient's presentation?