Internal Medicine

For each of the following patients presenting with a suspected zoonotic or tick-borne illness, identify the most appropriate targeted antimicrobial therapy.

Paramedics bring a 59-year-old woman to the emergency department after she reported severe dizziness and near-syncope at home. For the past two weeks, she has experienced worsening fatigue and an inability to lie flat without profound breathlessness. She has a history of left-sided breast cancer treated with lumpectomy and radiation therapy eight years ago, as well as a 30-pack-year smoking history. Current vital signs show a temperature of $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure of $86/52\text{ mm Hg}$ (which decreases to $72/45\text{ mm Hg}$ upon inspiration), heart rate of $122\text{/min}$, and respiratory rate of $26\text{/min}$. Arterial blood gas analysis on room air shows a pH of $7.50$, PaCO $_2$ of $28\text{ mm Hg}$, and PaO $_2$ of $88\text{ mm Hg}$. Physical examination reveals distended neck veins while sitting upright. Pulmonary auscultation shows clear breath sounds bilaterally. Cardiac auscultation reveals muffled heart sounds and no discernible murmurs. Extremities are cool to the touch without pitting edema. A 12-lead electrocardiogram demonstrates sinus tachycardia with beat-to-beat variation in the QRS complex amplitude. Which of the following is the most appropriate next step in the management of this patient?

A 26-year-old man is brought to the emergency department due to intractable, non-bilious vomiting for the past 4 days. He has type 1 diabetes mellitus and reports running out of his insulin prescription three days ago. He has been unable to tolerate any oral intake. He appears lethargic with dry mucous membranes. Vital signs show a heart rate of 118/min and blood pressure of 98/60 mm Hg.

Serum chemistry results are as follows:
$Na^+$: 142 mEq/L
$K^+$: 3.3 mEq/L
$Cl^-$: 90 mEq/L
$HCO_3^-$: 24 mEq/L
Blood urea nitrogen: 35 mg/dL
Creatinine: 1.4 mg/dL
Glucose: 520 mg/dL

Serum ketones are positive. Arterial blood gas (on room air) shows:
pH: 7.42
$pCO_2$: 38 mm Hg

Which of the following is the most accurate interpretation of this patient's acid-base status?

A 61-year-old man with a history of chronic obstructive pulmonary disease and ischemic cardiomyopathy is evaluated in the intensive care unit. He was intubated 6 days ago for acute respiratory failure. Three days ago, he developed a temperature of 38.9°C (102.0°F), increased purulent endotracheal secretions, and a new right lower lobe consolidation on his chest radiograph. A diagnosis of ventilator-associated pneumonia was made, and empiric therapy with intravenous vancomycin, cefepime, and amikacin was initiated. Today, his temperature is 37.4°C (99.3°F), and his oxygenation has improved. Endotracheal aspirate cultures obtained prior to antibiotic initiation grow Klebsiella pneumoniae. Susceptibility testing shows the isolate is resistant to ampicillin but susceptible to ceftriaxone, cefepime, and meropenem. Which of the following is the most appropriate next step in management?

A physician is evaluating a $35$-year-old female patient during a routine follow-up visit. She reports a $6$-month history of debilitating fatigue, chronic constipation, and generalized dry skin. The patient's last menstrual period occurred $18$ months ago, just prior to the delivery of her first child. Her medical history is significant for a complicated vaginal delivery that required an emergent blood transfusion due to severe postpartum hemorrhage. She currently takes no medications. Vital signs show a blood pressure of $96/60$ mmHg, a pulse of $54$/min, and respirations of $12$/min. Physical examination reveals delayed relaxation of deep tendon reflexes and loss of axillary and pubic hair. Laboratory studies reveal the following:

Thyroid-stimulating hormone (TSH): $1.8$ $\mu$ U/mL (Normal: $0.4$-$4.0$ $\mu$ U/mL)
Free thyroxine (T4): $0.5$ ng/dL (Normal: $0.9$-$1.7$ ng/dL)

Which of the following additional laboratory findings is most likely to be present in this patient?

A 28-year-old female teacher presents to the urgent care clinic complaining of a suddenly 'racing heart' that began 30 minutes ago while she was grading papers. She denies chest pain, shortness of breath, or lightheadedness. Her blood pressure is 122/78 mm Hg, pulse is 175/min, and respiratory rate is 16/min. Oxygen saturation is 99% on room air. A 12-lead electrocardiogram demonstrates a regular, narrow-complex tachycardia with no discernible P waves. Assuming each subsequent step fails to terminate the arrhythmia, arrange the following therapeutic interventions in the correct stepwise order of administration for this patient.

Following a weekend camping trip during which he consumed several undercooked beef patties, a $32$-year-old male is evaluated in the emergency department due to severe, crampy abdominal pain and frequent episodes of grossly bloody diarrhea. His symptoms began three days ago and have progressively worsened. The patient is otherwise healthy and takes no medications. Vital signs reveal a temperature of $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), a blood pressure of $122/78\text{ mmHg}$, and a pulse of $84/\text{min}$. Physical examination demonstrates a soft, non-distended abdomen with diffuse tenderness, but no rebound guarding or rigidity is appreciated.

The results of laboratory investigations are shown below:

A rapid stool assay returns positive for Shiga toxin. Which of the following is the most appropriate next step in the management of this patient?

A $58$-year-old man is evaluated in the hospital on day $4$ of admission for a pyogenic liver abscess. He initially presented with a $1$-week history of right upper quadrant pain, high-grade fever, and chills. On admission, computed tomography of the abdomen revealed a $5.5$-cm fluid collection in the right hepatic lobe. He underwent prompt percutaneous catheter drainage and was empirically started on intravenous piperacillin-tazobactam.

Over the past $48$ hours, his clinical condition has markedly improved. He is currently tolerating a regular diet and has been afebrile for two days. Current vital signs are:
Temperature: $37.1^\circ C$ ($98.8^\circ F$)
Blood pressure: $128/78$ mmHg
Pulse: $76/min$
Respirations: $14/min$

Laboratory results today show a leukocyte count of $8,500/\mu L$, down from $18,200/\mu L$ on admission. The percutaneous drain is currently putting out $10$ mL of serosanguinous fluid daily.

The abscess fluid culture from day $1$ has finalized and is growing *Streptococcus anginosus*. Susceptibility testing results are as follows:

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

A 29-year-old woman, G1P0 at $26$ weeks gestation, presents to the emergency department with progressively worsening shortness of breath, orthopnea, and intermittent blood-tinged sputum over the past two weeks. She recently emigrated from Southeast Asia and has had limited prenatal care. She is highly anxious but clearly states, "I want to do everything possible to keep my baby, no matter what happens to me. I refuse any procedure that will deliver my baby early." Vital signs show a temperature of $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure of $105/65$ mmHg, heart rate of $122$/min, respiratory rate of $26$/min, and oxygen saturation of $92\%$ on room air. Physical examination reveals an elevated jugular venous pressure. Lung auscultation demonstrates diffuse bilateral expiratory wheezes and bibasilar crackles. Cardiac auscultation at the left lateral decubitus position reveals a loud S1, an early diastolic extra sound, and a low-pitched mid-diastolic rumble. Which of the following is the most appropriate management plan for this patient?

Following three days of severe, watery diarrhea, a patient with known severe chronic obstructive pulmonary disease (COPD) is admitted to the intensive care unit for profound weakness, tachypnea, and somnolence. The patient has a remote history of a myocardial infarction but normal left ventricular ejection fraction on a recent echocardiogram.

Vital signs reveal a blood pressure of 88/56 mm Hg, heart rate of 115/min, respiratory rate of 28/min, and oxygen saturation of 91% on room air.

Physical examination demonstrates dry mucous membranes, prolonged capillary refill, and diffusely decreased breath sounds with faint end-expiratory wheezes. There is no jugular venous distention and no peripheral edema.

Laboratory analysis yields the following:

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

An $82$-year-old male is admitted to the inpatient ward after developing a high fever, severe global headache, and worsening lethargy over the past $24$ hours. His medical history includes hypertension, type 2 diabetes mellitus, and benign prostatic hyperplasia. Upon arrival, his temperature is $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), blood pressure is $112/68\text{ mmHg}$, and pulse is $108\text{/min}$. Physical examination demonstrates marked nuchal rigidity and disorientation to time and place. A lumbar puncture is promptly performed, and cerebrospinal fluid (CSF) analysis reveals a leukocyte count of $1,200/\mu\text{L}$ with $85\%$ neutrophils, a glucose level of $35\text{ mg/dL}$, and a protein level of $140\text{ mg/dL}$. He is empirically started on intravenous ceftriaxone, vancomycin, ampicillin, and dexamethasone. Two days later, the CSF culture confirms the growth of *Listeria monocytogenes*. Which of the following is the most appropriate next step in the antimicrobial management of this patient?

A 72-year-old man arrives at the emergency department via ambulance with sudden-onset, severe respiratory distress that woke him from sleep $45$ minutes ago. He has a history of poorly controlled essential hypertension, hyperlipidemia, and a 40-pack-year smoking history. Temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $225/118$ mm Hg, pulse is $112$/min, and respirations are $28$/min. Pulse oximetry shows an oxygen saturation of $86\%$ on room air. He is diaphoretic, speaking in one-word sentences, and using accessory muscles of respiration. Jugular venous distention is present when sitting upright. Auscultation reveals diffuse bilateral expiratory wheezes and bibasilar crackles. Cardiac examination shows regular tachycardia with a prominent S3 gallop. The electrocardiogram displays sinus tachycardia and voltage criteria for left ventricular hypertrophy without ischemic ST-segment or T-wave changes. Which of the following is the most appropriate next step in management?

During a cardiology clinical rotation, a group of medical students is learning to recognize distinct physical examination signs that point to specific underlying cardiac pathologies. Different arterial pulse contours can provide crucial clues to a patient's hemodynamic status. Match the following characteristic arterial pulse findings with their most commonly associated cardiovascular condition.

A 24-year-old man with a history of type 1 diabetes mellitus is brought to the emergency department with nausea, vomiting, and confusion. Blood pressure is 95/60 mm Hg, and heart rate is 120/min. Laboratory studies show:

Arrange the following interventions in the correct chronological sequence for the optimal acute management of this patient's condition.

A 34-year-old man with a recent history of emigration from a tuberculosis-endemic region presents to the emergency department complaining of a 4-week history of productive cough, intermittent hemoptysis, drenching night sweats, and a $5$-kg ($11$-lb) weight loss. His vital signs show a temperature of $38.2^\circ\text{C}$ ($100.8^\circ\text{F}$), blood pressure of $120/78\text{ mmHg}$, and oxygen saturation of $96\%$ on room air. Chest auscultation reveals bronchial breath sounds and crackles over the right upper lung field. A subsequent chest radiograph demonstrates a prominent cavitary infiltrate in the apical segment of the right upper lobe. Arrange the following management steps in the most appropriate chronological order to optimize both patient outcomes and infection control.

A 56-year-old woman is evaluated on the medical ward on hospital day 2. She was admitted the previous day for a rapidly spreading, painful, erythematous rash on her right lower leg. Her medical history is notable for type 2 diabetes mellitus and chronic venous insufficiency. On admission, her temperature was $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), heart rate was $110/\text{min}$, and blood pressure was $118/74\text{ mmHg}$. Physical examination revealed a well-demarcated, intensely red, warm, and tender plaque on the right anterior shin without any underlying fluctuance, purulent drainage, or overlying eschar. Due to the high fever and tachycardia, she was empirically started on intravenous vancomycin and piperacillin-tazobactam in the emergency department.

Today, the patient reports feeling much better. Her temperature is $37.4^\circ\text{C}$ ($99.3^\circ\text{F}$), heart rate is $82/\text{min}$, and blood pressure is $124/80\text{ mmHg}$. The margins of the erythema have not advanced. Blood cultures drawn on admission show no growth to date.

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

During a clinical skills workshop, medical students are reviewing the physiological effects of various dynamic bedside maneuvers on cardiac murmurs. Understanding how preload and afterload alter hemodynamics is critical for distinguishing similar-sounding murmurs. Match each cardiac pathology with its characteristic auscultatory response to these dynamic maneuvers.

Match each classic urinalysis sediment finding with its most likely associated renal pathology.

Match each Hepatitis B virus (HBV) serologic profile to the most accurate corresponding clinical status.

A 45-year-old man with a history of treated pulmonary tuberculosis is brought to the emergency department after coughing up approximately 800 mL of bright red blood over the past 8 hours. On arrival, he is in severe respiratory distress and coughing continuously. His blood pressure is 90/60 mm Hg, heart rate is 122/min, and oxygen saturation is 84% on room air. A bedside chest radiograph reveals a large cavitary lesion in the right upper lobe. Arrange the following interventions in the most appropriate sequential order for managing this patient's condition, starting with the most immediate priority and ending with the treatment of last resort.