Gastrointestinal Medicine Flashcards

Which of the following is the first-line treatment regimen for H. pylori eradication?

Answer: Triple therapy (PPI + amoxicillin + clarithromycin)

Triple therapy with a PPI, amoxicillin, and clarithromycin for 14 days is the standard first-line regimen for H. pylori eradication in areas with low clarithromycin resistance.

A 45-year-old patient reports heartburn and regurgitation occurring at least twice weekly for 6 months. What is the most appropriate first-line pharmacological treatment?

Answer: Proton pump inhibitor (e.g., omeprazole)

PPIs provide superior acid suppression compared to H2 blockers and are the first-line pharmacological therapy for chronic GERD.

According to Rome IV criteria, which of the following is NOT a diagnostic criterion for irritable bowel syndrome (IBS)?

Answer: Unintentional weight loss >10 lbs

Unintentional weight loss is a red-flag symptom suggesting organic disease and is not part of the Rome IV IBS criteria; its presence warrants further workup.

Which antibody test is the preferred initial screening test for celiac disease in patients with adequate IgA levels?

Answer: Anti-tissue transglutaminase IgA (anti-tTG IgA)

Anti-tTG IgA is the single best screening test for celiac disease due to its high sensitivity (>95%) and specificity (~95%) and is recommended by all major guidelines.

A 62-year-old otherwise healthy patient is diagnosed with uncomplicated acute diverticulitis (no abscess, no perforation, mild symptoms). What is the most appropriate management?

Answer: Outpatient treatment with oral antibiotics and liquid diet

Uncomplicated diverticulitis in immunocompetent patients with mild symptoms can be safely managed outpatient with oral antibiotics and dietary modification.

According to current USPSTF guidelines, at what age should average-risk asymptomatic adults begin colorectal cancer screening?

Answer: 45 years

In 2021, the USPSTF updated its recommendation to begin colorectal cancer screening at age 45 for average-risk adults due to rising incidence in younger populations.

Which of the following is the most common etiology of peptic ulcer disease in the United States?

Answer: Helicobacter pylori infection

H. pylori infection is responsible for approximately 70–90% of duodenal ulcers and 60–70% of gastric ulcers, making it the leading cause of peptic ulcer disease.

Which hepatitis B serologic pattern indicates immunity due to vaccination (not prior infection)?

Answer: Anti-HBs positive only (HBsAg negative, anti-HBc negative)

Vaccination generates anti-HBs without anti-HBc, because vaccines contain only surface antigen; natural infection also produces anti-HBc.

Which of the following is the most common cause of acute pancreatitis in the United States?

Answer: Gallstones

Gallstones account for approximately 40–70% of acute pancreatitis cases, as a stone obstructing the common bile duct can impair pancreatic enzyme drainage.

Which endoscopic finding is more characteristic of Crohn's disease than ulcerative colitis?

Answer: Skip lesions with areas of normal intervening mucosa

Crohn's disease characteristically produces patchy, discontinuous 'skip lesions,' whereas ulcerative colitis shows continuous mucosal inflammation extending proximally from the rectum.

A 52-year-old patient with chronic constipation has failed dietary fiber supplementation and increased fluid intake. Which pharmacological agent is the most appropriate next step?

Answer: Polyethylene glycol (osmotic laxative)

Polyethylene glycol is the preferred first-line pharmacological agent for chronic constipation, with strong evidence for efficacy and long-term safety.

A 28-year-old traveler returns from Central America with 4 days of watery, non-bloody diarrhea and mild cramping but no fever. What is the most appropriate initial management?

Answer: Oral rehydration therapy and supportive care

Mild traveler's diarrhea without fever, bloody stools, or systemic symptoms is self-limiting; oral rehydration and supportive care are sufficient management.

Which intervention has the strongest evidence for improving liver histology in non-alcoholic fatty liver disease (NAFLD)?

Answer: Weight loss of 7–10% of body weight through diet and exercise

Lifestyle modification achieving 7–10% weight loss is the most effective intervention for NAFLD, consistently improving steatosis, inflammation, and fibrosis on histology.

A 38-year-old woman with episodic right upper quadrant pain after fatty meals has an ultrasound confirming cholelithiasis. She has no fever, jaundice, or signs of acute cholecystitis. What is the definitive treatment?

Answer: Elective laparoscopic cholecystectomy

Symptomatic cholelithiasis is definitively treated with elective laparoscopic cholecystectomy, which eliminates the risk of future complications including acute cholecystitis and gallstone pancreatitis.

A 72-year-old man presents with painless, large-volume bright red blood per rectum. Vital signs are stable. What is the most likely cause?

Answer: Diverticular bleeding

Diverticular disease is the leading cause of significant lower GI bleeding in adults over 60, accounting for 30–40% of cases, and typically presents as painless, high-volume hematochezia.

Which diagnostic procedure is the preferred initial evaluation for a patient presenting with hematemesis and hemodynamic stability?

Answer: Esophagogastroduodenoscopy (EGD)

EGD is the gold-standard first-line test for upper GI bleeding because it simultaneously identifies the bleeding source and allows therapeutic intervention (e.g., banding, injection, cautery).

Barrett's esophagus is best defined as which of the following histological changes?

Answer: Replacement of normal squamous epithelium with intestinal-type columnar epithelium

Barrett's esophagus is a metaplastic change where normal esophageal squamous epithelium is replaced by specialized intestinal columnar epithelium, typically from chronic gastric acid reflux.

A patient presents with jaundice, generalized pruritus, dark urine, and clay-colored stools. Lab results show markedly elevated direct bilirubin and alkaline phosphatase. What type of jaundice does this pattern represent?

Answer: Cholestatic (obstructive) jaundice

Elevated direct (conjugated) bilirubin, alkaline phosphatase, and the clinical features of pruritus, dark urine, and pale stools indicate obstruction of bile flow (cholestatic jaundice).

Which of the following is the most common cause of small bowel obstruction in adults in developed countries?

Answer: Intra-abdominal adhesions from prior surgery

Post-surgical intra-abdominal adhesions account for approximately 60–75% of small bowel obstructions, making them by far the most common etiology in patients with prior abdominal surgery.

A 24-year-old male presents with periumbilical pain that migrated to the right lower quadrant over 12 hours, accompanied by nausea, low-grade fever, and leukocytosis. Which physical exam finding is most classic for acute appendicitis?

Answer: Rebound tenderness at McBurney's point

Rebound tenderness at McBurney's point—located one-third the distance from the right anterior superior iliac spine to the umbilicus—is the classic physical finding of peritoneal irritation in acute appendicitis.