ABIM Gastroenterology 1 — Questions and Answers
Question 1: A 55-year-old man presents with melena and hematemesis. Upper endoscopy shows a duodenal ulcer with a visible vessel. What is the most appropriate endoscopic treatment?
- Biopsy the ulcer and observe
- Epinephrine injection plus thermal coagulation or clip (Correct answer)
- Epinephrine injection alone
- Observe and start PPI only
Correct answer: Epinephrine injection plus thermal coagulation or clip
Combination therapy (epinephrine plus thermal therapy or clips) is superior to epinephrine injection alone for high-risk ulcers with visible vessels or active bleeding.
Question 2: A 40-year-old woman presents with watery diarrhea, flushing, and wheezing. Urinary 5-HIAA is markedly elevated. CT scan shows a liver mass and ileal mass. What is the diagnosis?
- VIPoma
- Carcinoid tumor (neuroendocrine tumor) with carcinoid syndrome (Correct answer)
- Glucagonoma
- Gastrinoma
Correct answer: Carcinoid tumor (neuroendocrine tumor) with carcinoid syndrome
Carcinoid syndrome (flushing, diarrhea, wheezing) occurs when neuroendocrine tumors with liver metastases secrete serotonin directly into systemic circulation, elevated urinary 5-HIAA confirms the diagnosis.
Question 3: A 35-year-old woman with ulcerative colitis has been on mesalamine for 2 years. She develops worsening diarrhea and rectal bleeding despite treatment. Colonoscopy shows pancolitis. What is the next step?
- Increase mesalamine dose only
- Add oral corticosteroids for acute flare management (Correct answer)
- Proceed immediately to colectomy
- Start antibiotics alone
Correct answer: Add oral corticosteroids for acute flare management
Moderate-to-severe UC flares unresponsive to mesalamine are managed with oral corticosteroids to induce remission, followed by consideration of immunomodulators or biologics.
Question 4: A patient with cirrhosis and ascites presents with fever, abdominal pain, and confusion. Paracentesis shows PMN count of 350 cells/mm³. What is the diagnosis and treatment?
- Hepatic encephalopathy — start lactulose
- Spontaneous bacterial peritonitis — start IV cefotaxime (Correct answer)
- Secondary peritonitis — emergency surgery
- Hepatorenal syndrome — start terlipressin
Correct answer: Spontaneous bacterial peritonitis — start IV cefotaxime
SBP is diagnosed by ascitic fluid PMN count ≥250 cells/mm³ and treated empirically with IV third-generation cephalosporin (cefotaxime) without waiting for culture results.
Question 5: A 50-year-old man with Barrett esophagus (non-dysplastic, confirmed on two endoscopies) asks about surveillance. What is the recommended surveillance interval?
- Every 6 months
- Every 1 year
- Every 3–5 years (Correct answer)
- No further surveillance needed
Correct answer: Every 3–5 years
Non-dysplastic Barrett esophagus has a low malignant potential (~0.3% per year), and current guidelines recommend surveillance endoscopy every 3–5 years.
Question 6: A 65-year-old man is found to have a 1.5 cm polyp removed during colonoscopy. Pathology shows a tubular adenoma with low-grade dysplasia. When should his next surveillance colonoscopy be performed?
- 1 year
- 3 years (Correct answer)
- 5–10 years
- No follow-up needed
Correct answer: 3 years
A single tubular adenoma <10 mm with low-grade dysplasia warrants repeat colonoscopy in 3 years per current surveillance guidelines.
ABIM Gastroenterology 1
A 55-year-old man presents with melena and hematemesis.
Upper endoscopy shows a duodenal ulcer with a visible vessel.
What is the most appropriate endoscopic treatment?