Gastroenterology and Hepatology

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 $58$-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 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 $65$-year-old man presents to the clinic with a $3$-month history of progressive difficulty swallowing both solids and liquids. He reports frequent regurgitation of undigested food, especially at night, and an unintended weight loss of $8$ kg ($17.6$ lb) during this period. His medical history is significant for hypertension and a $40$-pack-year smoking history. Vital signs are within normal limits. Physical examination is unremarkable. A barium esophagram demonstrates esophageal dilation with symmetric, smooth tapering at the gastroesophageal junction. Upper gastrointestinal endoscopy shows retained food debris in the esophageal body but normal overlying mucosa; the endoscope passes easily into the stomach with gentle pressure. High-resolution esophageal manometry demonstrates absent peristalsis in the esophageal body and a high integrated relaxation pressure, indicating failure of the lower esophageal sphincter to relax upon swallowing. Which of the following is the most appropriate next step in management?

A 54-year-old woman with a long-standing history of severe alcohol use disorder is brought to the emergency department by emergency medical services after vomiting large amounts of bright red blood at home. On arrival, she is lethargic and confused. Her blood pressure is 82/50 mm Hg, and her pulse is 128/min. Physical examination reveals marked scleral icterus, multiple spider angiomas on the chest, and a visibly distended abdomen with shifting dullness. The emergency physician suspects acute variceal hemorrhage as the cause of her instability. Arrange the following management steps in the most appropriate chronological sequence for this patient.

Match each esophageal motility disorder with its most characteristic finding on high-resolution esophageal manometry.

A $64$-year-old man with a history of alcohol-related cirrhosis and major depressive disorder is hospitalized for worsening abdominal distension and fever. His home medications include spironolactone, furosemide, lactulose, and citalopram. On admission, his temperature is $38.1$°C ($100.6$°F) and blood pressure is $105/65$ mmHg. Physical examination reveals shifting dullness and trace bilateral pedal edema.

Diagnostic paracentesis yields ascitic fluid with a leukocyte count of $1,100$/mm³ ($85\%$ neutrophils). Arterial blood gas analysis on room air reveals:
pH: $7.29$
pCO $_2$: $29$ mmHg
HCO $_3^-$: $14$ mEq/L

The patient is empirically started on intravenous piperacillin-tazobactam and vancomycin, and he receives intravenous albumin on hospital day 1. On hospital day 3, his temperature has decreased to $37.1$°C ($98.8$°F) and his abdominal pain has resolved. The ascitic fluid culture from admission grows *Escherichia coli* that is resistant to ampicillin but susceptible to ceftriaxone, cefepime, piperacillin-tazobactam, and ciprofloxacin. Blood cultures show no growth.

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

A 59-year-old man with a known history of alcohol-related cirrhosis is brought to the emergency department by his family due to increasing confusion, lethargy, and diffuse abdominal discomfort over the past $48$ hours. His home medications include nadolol, spironolactone, and furosemide. His temperature is $37.8^\circ\text{C}$ ($100.0^\circ\text{F}$), pulse is $92/\text{min}$, blood pressure is $105/65\text{ mmHg}$, and respirations are $16/\text{min}$. Physical examination reveals scleral icterus and spider angiomas. The abdomen is distended with shifting dullness and diffuse, mild tenderness to palpation without rebound or guarding. Asterixis is present on neurologic examination.

A diagnostic paracentesis is performed, and ascitic fluid analysis reveals a total protein of $1.1\text{ g/dL}$ and a leukocyte count of $650/\text{mm}^3$ with $75\%$ neutrophils.

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

Match each Hepatitis B (HBV) serologic and virologic profile to its corresponding clinical disease state.

A $68$-year-old man is evaluated on postoperative day $5$ following a partial colectomy for recurrent uncomplicated diverticulitis. Over the past $24$ hours, he has developed a fever, tachycardia, and new-onset copious, watery diarrhea. He reports mild, diffuse abdominal cramping but no nausea or vomiting. His current medications include intravenous fluids, prophylactic subcutaneous enoxaparin, and patient-controlled analgesia. He received a standard course of perioperative intravenous cefoxitin. His temperature is $38.6^\circ\text{C}$ ($101.5^\circ\text{F}$), blood pressure is $118/74 \text{ mm Hg}$, and pulse is $112/\text{min}$. On physical examination, the abdomen is mildly distended and diffusely tender to deep palpation, without rigidity or rebound tenderness. The surgical incision is clean, dry, and intact.

Laboratory studies show:
Leukocyte count: $18,500/\text{mm}^3$

Arterial blood gas (room air):
pH: $7.32$
pCO $_2$: $30 \text{ mm Hg}$
HCO $_3^-$: $15 \text{ mEq/L}$

A stool enzyme immunoassay (EIA) is positive for *Clostridioides difficile* toxins A and B.

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

During bedside rounds on the medical-surgical ward, a clinical team evaluates a patient on hospital day $4$. The patient was initially admitted for severe acute pancreatitis secondary to cholelithiasis. Despite adequate initial volume resuscitation, the patient has required continuous nasojejunal enteral nutrition and aggressive pain management for unremitting epigastric discomfort.

Vital signs demonstrate a temperature of $38.1^\circ\text{C}$ ($100.6^\circ\text{F}$), a heart rate of $112\text{/min}$, respirations of $18\text{/min}$, and a blood pressure of $116/72\text{ mm Hg}$.

Physical examination reveals a distended abdomen with marked epigastric tenderness. Bowel sounds are hypoactive. No scleral icterus is present.

Laboratory analysis shows:
Leukocyte count: $15,800\text{/mm}^3$
Hemoglobin: $14.2\text{ g/dL}$
Blood urea nitrogen: $28\text{ mg/dL}$
Total bilirubin: $0.9\text{ mg/dL}$ (decreased from $3.2\text{ mg/dL}$ on admission)
Alkaline phosphatase: $110\text{ U/L}$ (decreased from $340\text{ U/L}$ on admission)
Alanine aminotransferase (ALT): $45\text{ U/L}$ (decreased from $450\text{ U/L}$ on admission)

Due to the persistent systemic inflammatory response syndrome (SIRS) and severe pain, a contrast-enhanced computed tomography (CT) scan of the abdomen is obtained. The imaging demonstrates diffuse pancreatic enlargement with interstitial edema and $>30\%$ non-enhancement of the pancreatic parenchyma, consistent with acute necrotizing pancreatitis. Several acute peripancreatic fluid collections are noted. There is no evidence of retroperitoneal gas or pneumobilia.

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

Match each esophageal disorder with its most characteristic diagnostic finding on imaging or endoscopy.

A 28-year-old man comes to the clinic reporting a 2-day history of watery, non-bloody diarrhea. He reports passing 4 to 5 loose bowel movements per day, accompanied by mild, diffuse abdominal cramping. He denies having any fever, nausea, vomiting, or recent travel history. He has no significant past medical history, takes no medications, and has had no recent sick contacts. Vital signs include a temperature of 37.1°C (98.8°F), blood pressure of 118/76 mmHg, pulse of 82/min, and respiratory rate of 14/min. Physical examination reveals a soft, non-distended abdomen with mild diffuse tenderness and hyperactive bowel sounds. There is no rebound tenderness or guarding. Which of the following is the most appropriate next step in the management of this patient?

Identify the defining serologic or biochemical marker that is most specific for diagnosing each of the following hepatobiliary conditions.

A 68-year-old man is hospitalized for community-acquired pneumonia and treated with intravenous ceftriaxone and azithromycin. On day 5 of his admission, he develops new-onset frequent, watery diarrhea, mild diffuse abdominal pain, and a temperature of 38.2°C (100.8°F). His vital signs are otherwise stable, and physical examination reveals mild lower abdominal tenderness without rebound or guarding. The medical team suspects an infectious complication related to his recent pharmacotherapy. Arrange the following management steps in the most appropriate chronological sequence for addressing this new complication.

An inpatient medical team is evaluating a 62-year-old man with a known history of decompensated alcohol-associated cirrhosis who developed worsening confusion and lethargy over the past 24 hours. He has a past medical history of chronic obstructive pulmonary disease. His wife, who is his legally appointed healthcare proxy, is at the bedside; his estranged son is also present and frequently interrupts the care team to demand interventions. Vital signs are within normal limits. Physical examination reveals scleral icterus, a moderately distended abdomen with shifting dullness, and a coarse, flapping tremor of the hands when the wrists are extended. Laboratory evaluation demonstrates an elevated serum ammonia level, a normal thyroid-stimulating hormone level with a slightly decreased free T4, and a urinalysis showing $>10^5$ colony-forming units/mL of Escherichia coli without leukocyte esterase or nitrites. The patient denies dysuria or urinary frequency. An arterial blood gas reveals a normal partial pressure of carbon dioxide. The son demands that the team immediately insert a feeding tube to provide nutrition. Which of the following is the most appropriate next step in the management of this patient?

A 68-year-old woman is evaluated in the hospital on day 3 of admission for acute cholangitis. She initially presented with fever, right upper quadrant pain, and jaundice. She was started on empiric intravenous piperacillin-tazobactam and successfully underwent endoscopic retrograde cholangiopancreatography with biliary stone extraction.

Currently, she is afebrile and her abdominal pain has entirely resolved. Blood and bile cultures obtained on admission both grow *Klebsiella pneumoniae*. The antimicrobial susceptibility report is as follows:

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

During morning rounds, the care team reviews the chart of a 71-year-old woman who is currently receiving inpatient treatment for acute ascending cholangitis. She was admitted three days ago with a temperature of 39.2°C (102.6°F), severe right upper quadrant pain, and scleral icterus. On the day of admission, blood cultures were drawn, and she was started on empiric intravenous piperacillin-tazobactam. The following day, she underwent an urgent endoscopic retrograde cholangiopancreatography (ERCP), during which a 12-mm common bile duct stone was successfully extracted, restoring normal biliary flow. Today, the patient reports feeling significantly better and is tolerating a liquid diet. Her vital signs are a temperature of 37.0°C (98.6°F), blood pressure of 122/76 mm Hg, and pulse of 78/min. Laboratory studies show her leukocyte count has normalized to 7,500/mm³. The microbiology laboratory reports that the admission blood cultures are positive for *Escherichia coli*. The susceptibility panel confirms the isolate is resistant to ampicillin but highly susceptible to ceftriaxone, ciprofloxacin, and piperacillin-tazobactam. Which of the following is the most appropriate next step in the pharmacologic management of this patient?