Internal Medicine

An 82-year-old man residing in a long-term care facility is evaluated during a routine monthly visit. The facility staff report that over the past two days, his urine collection bag has contained visibly cloudy and notably malodorous urine. He has a chronic indwelling urethral catheter that was placed six months ago for severe urinary retention secondary to advanced benign prostatic hyperplasia. The patient currently has no complaints. He denies chills, abdominal discomfort, or flank pain. His appetite is normal, and he has been actively participating in his usual group activities. His temperature is 37.1°C (98.8°F), blood pressure is 130/80 mm Hg, heart rate is 76/min, and respiratory rate is 14/min. Physical examination reveals a soft, non-tender abdomen with no costovertebral angle tenderness. The urethral meatus shows no erythema or purulent discharge. A urinalysis obtained by the staff earlier today demonstrates positive leukocyte esterase, positive nitrites, and 45 leukocytes/hpf. Which of the following is the most appropriate next step in management?

A $48$-year-old man is evaluated in the hospital for new-onset exertional dyspnea, fatigue, and lightheadedness over the past $24$ hours. He was admitted $6$ days ago for native aortic valve infective endocarditis caused by *Streptococcus mitis*. Blood cultures demonstrated that the organism is highly susceptible to penicillin, and he has been receiving targeted intravenous aqueous crystalline penicillin G. His temperature is $37.4^\circ\text{C}$ ($99.3^\circ\text{F}$), blood pressure is $102/60 \text{ mm Hg}$, pulse is $42/\text{min}$, and respirations are $18/\text{min}$. Physical examination reveals a harsh, early diastolic decrescendo murmur at the left sternal border. The lungs are clear to auscultation. Electrocardiogram reveals sinus rhythm with a PR interval of $280 \text{ ms}$ (first-degree atrioventricular block) and a new left bundle branch block. Laboratory studies show a leukocyte count of $8,500/\text{mm}^3$, a thyroid-stimulating hormone (TSH) level of $0.2 \text{ \mu U/mL}$ (Normal: $0.4$-$4.0 \text{ \mu U/mL}$), and a free T4 of $0.7 \text{ ng/dL}$ (Normal: $0.9$-$2.4 \text{ ng/dL}$). The patient is currently lethargic and lacks medical decision-making capacity. His brother is at the bedside and demands that the medical team immediately switch the antibiotics to a "stronger" regimen, but the patient's advance directive legally appoints his wife, who is en route to the hospital, as his healthcare proxy. Which of the following is the most appropriate next step in the management of this patient?

A 71-year-old man is evaluated in the intensive care unit for new-onset abdominal distension and altered mental status. He was admitted one week ago for treatment of healthcare-associated pneumonia and has been receiving intravenous piperacillin-tazobactam. Two days ago, he developed multiple episodes of watery diarrhea, but he has had no bowel movements for the past $18 \text{ hours}$. Current temperature is $38.8^\circ\text{C}$ ($101.8^\circ\text{F}$), blood pressure is $86/54 \text{ mmHg}$, pulse is $122/\text{min}$, and respirations are $24/\text{min}$. Physical examination reveals a lethargic patient. The abdomen is grossly distended, tympanic to percussion, and diffusely tender with absent bowel sounds.

Laboratory results are as follows:

An abdominal plain film shows a transverse colon diameter of $8.5 \text{ cm}$ without free intraperitoneal air. Stool enzyme immunoassay is positive for both glutamate dehydrogenase antigen and *Clostridioides difficile* toxins A and B. Which of the following is the most appropriate pharmacologic intervention?

A series of patients are evaluated in the endocrinology clinic for calcium homeostasis disorders. The laboratory reference ranges are as follows:

* Serum calcium: $8.4-10.2$ mg/dL
* Serum phosphorus: $2.7-4.5$ mg/dL
* Intact parathyroid hormone (PTH): $10-65$ pg/mL

Match each patient's serum laboratory profile with the most likely underlying pathophysiologic diagnosis.

A medical intensive care unit team is reviewing the chart of a $54$-year-old man on hospital day $9$. He was initially admitted and intubated for airway protection following a severe traumatic brain injury. Three days ago, he developed a fever, increased purulent endotracheal secretions, and a new right lower lobe consolidation on chest radiograph. He was diagnosed with ventilator-associated pneumonia and started on empiric intravenous vancomycin and cefepime.

Today, his temperature is $37.4^\circ\text{C}$ ($99.3^\circ\text{F}$), blood pressure is $122/78$ mmHg, and heart rate is $88$/min. Endotracheal secretions have significantly decreased. The bronchoalveolar lavage culture collected three days ago has finalized, growing *Haemophilus influenzae* that is susceptible to ceftriaxone, levofloxacin, and piperacillin-tazobactam.

Current ventilator settings (Volume Assist-Control mode):
- Respiratory rate: $12$/min
- Tidal volume: $450$ mL ($6$ mL/kg ideal body weight)
- $\text{FiO}_2$: $0.40$
- PEEP: $5$ cm $\text{H}_2\text{O}$

An arterial blood gas analysis reveals:
- $\text{pH}$: $7.28$
- $\text{PaCO}_2$: $56$ mmHg
- $\text{PaO}_2$: $82$ mmHg
- $\text{HCO}_3^-$: $25$ mEq/L

Which of the following are appropriate modifications to this patient's management plan? (Select all that apply)

A 70-year-old man is brought to the emergency department from a skilled nursing facility due to a 2-day history of worsening fever, right upper quadrant abdominal pain, and new-onset confusion. His past medical history is significant for hypertension and osteoarthritis. His temperature is 39.2°C (102.6°F), blood pressure is 88/54 mm Hg, pulse is 118/min, and respiratory rate is 22/min. Physical examination reveals scleral icterus, dry mucous membranes, and significant tenderness to palpation in the right upper quadrant without rebound or guarding. Laboratory studies demonstrate a leukocyte count of 18,500/mm³, total bilirubin of 5.2 mg/dL, direct bilirubin of 4.1 mg/dL, and alkaline phosphatase of 450 U/L.

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

Match each clinical scenario requiring targeted antimicrobial prophylaxis with the most appropriate guideline-concordant regimen.

Match each characteristic hemodynamic profile or physical examination finding with the most likely underlying cardiovascular pathology.

A 68-year-old man is evaluated on postoperative day 6 following an elective right inguinal hernia repair. On postoperative day 3, he developed a cough, fever, and right-sided chest pain. A chest radiograph at that time revealed a right lower lobe infiltrate. Sputum cultures grew *Streptococcus pneumoniae* sensitive to ceftriaxone, and he was appropriately started on targeted intravenous ceftriaxone therapy. Today, the patient reports worsening dyspnea and persistent pleuritic chest pain. His temperature has spiked to $38.8^\circ\text{C}$ ($101.8^\circ\text{F}$). Blood pressure is 118/76 mmHg, pulse is 112/min, and respirations are 26/min. Pulse oximetry shows 91% on room air. Physical examination reveals decreased breath sounds and dullness to percussion at the right lung base. Jugular venous pressure is 6 cm H $_2$ O, and there is no lower extremity edema.

An arterial blood gas analysis on room air shows:

A repeat chest radiograph demonstrates the known right lower lobe infiltrate and a new, moderate-sized, free-flowing right pleural effusion. A diagnostic thoracentesis is performed, yielding cloudy yellow fluid.

Pleural fluid analysis shows:

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

A 22-year-old woman with type 1 diabetes mellitus is brought to the emergency department with severe abdominal pain, nausea, vomiting, and lethargy. She missed her last several doses of insulin due to a recent gastrointestinal illness. Vital signs show a blood pressure of 90/60 mm Hg, heart rate of 124/min, and respiratory rate of 28/min with deep, rapid breaths. Laboratory testing reveals:

* Blood glucose: 540 mg/dL
* Arterial blood gas pH: 7.18
* Serum bicarbonate: 10 mEq/L
* Serum potassium: 4.8 mEq/L
* Serum ketones: positive

Arrange the following acute management steps in the correct chronological sequence for this patient's presentation.

Evaluate the clinical presentations of esophageal dysphagia and match each patient to the most likely corresponding findings on diagnostic evaluation (esophageal manometry or upper endoscopy).

A 48-year-old female presents to the emergency department with severe, constant epigastric pain that radiates to her mid-back. The pain began 12 hours ago and has been accompanied by multiple episodes of non-bilious emesis. She denies alcohol consumption, recent travel, or new medications.

Vital signs:
- Temperature: 38.2°C (100.8°F)
- Blood pressure: 112/68 mmHg
- Heart rate: 118/min
- Respiratory rate: 22/min

Physical examination reveals a distressed patient with severe epigastric tenderness to deep palpation, without guarding or rebound. Bowel sounds are hypoactive.

Laboratory results:
| Leukocyte count | $16,500/\text{mm}^3$ |
| Lipase | $4,200 \text{ U/L}$ |
| Total bilirubin | $1.0 \text{ mg/dL}$ |
| Aspartate aminotransferase (AST) | $110 \text{ U/L}$ |
| Alanine aminotransferase (ALT) | $155 \text{ U/L}$ |
| Thyroid-stimulating hormone (TSH) | $0.2 \mu\text{U/mL}$ (Normal: 0.5–5.0) |
| Free T4 | $1.2 \text{ ng/dL}$ (Normal: 0.9–1.7) |

Arterial blood gas (room air):
| pH | $7.32$ |
| $\text{pCO}_2$ | $32 \text{ mmHg}$ |
| $\text{HCO}_3^-$ | $16 \text{ mEq/L}$ |

An abdominal ultrasound demonstrates multiple echogenic foci within the gallbladder lumen with posterior acoustic shadowing. The common bile duct measures 4 mm in diameter, and the gallbladder wall is 2 mm thick without pericholecystic fluid. The pancreas is partially obscured by overlying bowel gas.

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

A $36$-year-old woman, G2P2, comes to the emergency department due to a $3$-day history of progressively worsening shortness of breath and an inability to lie flat. She delivered a healthy infant via an uncomplicated spontaneous vaginal delivery $3$ weeks ago. Her medical history is significant for mild asthma, which has been controlled without regular medications for the past five years. She takes no medications and does not use tobacco, alcohol, or illicit substances. Her temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $118/76\text{ mmHg}$, heart rate is $112/\text{min}$, and respiratory rate is $24/\text{min}$. Pulse oximetry shows an oxygen saturation of $88\%$ on room air. Physical examination demonstrates jugular venous distension up to $9\text{ cm H}_2\text{O}$ above the sternal angle. Auscultation of the lungs reveals bilateral fine bibasilar crackles with scattered expiratory wheezes. Cardiac examination shows a regular, rapid rhythm, a prominent third heart sound ($S_3$), and a grade $2/6$ holosystolic murmur best heard at the apex. The lower extremities show $2+$ bilateral pitting edema. Which of the following is the most appropriate initial pharmacological management for this patient?

A 62-year-old man receiving home total parenteral nutrition for short bowel syndrome is admitted to the hospital with a new-onset fever of 39.2°C (102.6°F) and rigors. His symptoms began shortly after flushing his tunneled central venous catheter at home. His blood pressure is 110/70 mm Hg, heart rate is 105/min, and respiratory rate is 18/min. Physical examination reveals a clean, intact catheter exit site with no erythema or purulence. He has no known drug allergies. The physician suspects a catheter-related bloodstream infection (CRBSI) and formulates a management plan.

Arrange the following clinical interventions in the most appropriate chronological order from the time of patient presentation to the implementation of final definitive therapy.

A radiologist is reviewing multiphasic computed tomography (CT) scans of the liver for several adult patients. Match each clinical and radiologic presentation with its most likely diagnosis.

Match the following clinical patient vignettes with their most likely corresponding calcium, phosphorus, and parathyroid hormone (PTH) laboratory profiles.

A $67$-year-old woman with a severe history of emphysema is brought to the emergency department reporting a three-day history of increasing cough, purulent sputum, and breathlessness. Upon arrival, initial therapies including supplemental oxygen via nasal cannula, nebulized short-acting bronchodilators, and intravenous glucocorticoids are administered. Reevaluation ninety minutes later reveals that the patient is markedly fatigued and utilizing accessory muscles of respiration. She remains fully conscious and cooperative but struggles to speak in full sentences. Vital signs show a respiratory rate of $28$/min and an oxygen saturation of $89\%$ on $4$ L/min of oxygen. Arrange the following clinical interventions in the most appropriate chronological sequence for escalating the management of this patient's respiratory deterioration.

A 68-year-old man comes to the clinic due to a 6-week history of progressively worsening shortness of breath and a dry, nonproductive cough. He has a history of hypertension, type 2 diabetes mellitus, and symptomatic paroxysmal atrial fibrillation. His medications include amiodarone, metoprolol, apixaban, and lisinopril. The patient has never smoked. His temperature is 37.1°C (98.8°F), blood pressure is 128/82 mm Hg, pulse is 68/min, and respirations are 22/min. Pulse oximetry shows 91% on room air. Physical examination reveals fine, bilateral inspiratory crackles at the lung bases. Cardiac examination shows a regular rate and rhythm with normal S1 and S2; there are no murmurs or gallops. Jugular venous pressure is 6 cm $H_2O$. There is no lower extremity edema. Laboratory studies show a normal leukocyte count and a brain natriuretic peptide (BNP) level of 65 pg/mL. Thyroid-stimulating hormone (TSH) is 5.8 $\mu$ U/mL (normal: 0.4-4.0 $\mu$ U/mL) and free T4 is 1.1 ng/dL (normal: 0.9-1.7 ng/dL). Chest radiography demonstrates diffuse, bilateral interstitial opacities. Electrocardiography shows normal sinus rhythm. Which of the following is the most appropriate next step in management?

A 68-year-old man is evaluated in the intensive care unit on day 6 of hospitalization for septic shock secondary to community-acquired pneumonia. His hemodynamics have stabilized, and his vasopressor requirements are being steadily weaned. He remains mechanically ventilated. His medical history includes type 2 diabetes mellitus and hypertension. His family reports that prior to this admission, he was highly active and had no fatigue, weight changes, or cold intolerance. His temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $115/70\text{ mm Hg}$, and heart rate is $82/\text{min}$. Physical examination shows no goiter or thyroid tenderness. Due to a prolonged intensive care stay, a thyroid function panel is ordered. Laboratory results show:

Thyroid-stimulating hormone (TSH): $0.25\text{ }\mu\text{U/mL}$ (Normal: $0.4-4.0\text{ }\mu\text{U/mL}$)
Free thyroxine (T4): $0.7\text{ ng/dL}$ (Normal: $0.9-1.7\text{ ng/dL}$)
Total triiodothyronine (T3): $45\text{ ng/dL}$ (Normal: $80-200\text{ ng/dL}$)

Which of the following is the most appropriate next step in the management of this patient's thyroid findings?

During a cardiology rotation, a medical student is evaluating several patients with distinct heart murmurs. The attending physician emphasizes the importance of dynamic auscultatory maneuvers in differentiating structural cardiac defects based on how alterations in preload and afterload affect intracardiac hemodynamics. Correlate each patient's specific auscultatory response with the most likely underlying cardiovascular condition.